Special Edition - December 2023 by Revista Aapresid

TOPICAL NEWS 2

REVISTA AAPRESID

04 EDITORIAL Networking that creates bridges and heals wounds

INSTITUTIONAL

Argentina benefited from its local condition in front of farmers all around the world

INSTITUCIONAL

Redefining innovation: different means for current agrifood systems

INSTITUCIONAL

Aapresid touring across Europe

SCIENCE AND AGRIBUSINESS

Agriculture based on artificial intelligence

SCIENCE AND AGRIBUSINESS

Safe and sound soils

BIOECONOMY

CROP NUTRITION

A journey across Cuyo region’s bioeconomy

Two sides of the same nutrient

CROP MANAGEMENT

Gold-worth-residues

CROP NUTRITION

Biological innovation to optimize wheat production

CROP NUTRITION

Adjusting corn nutrition over predecessor Vicia villosa

CROP NUTRITION

The keys to close the breach

ALTERNATIVE PRODUCTION

A toast between vines and vicia

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ALTERNATIVE PRODUCTION

Bombilla Guaraní, a toucan-related enigma revealed by Jesuits, and the ‘gracias’ traveling from Argentina to the Middle East: the amazing story of Yerba Mate

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ALTERNATIVE PRODUCTION

Coffee with sustainable aroma: Argentina joins Latin America’s organic production revolution

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LIVESTOCK FARMING

Livestock farming and N2O emissions. Planning for data to play at home.

EDITORIAL Networking that creates bridges and heals wounds For over 34 years, the Argentine No-Till Farmers Association (Aapresid) has been promoting a production model that became almost a rite for most Argentinian producers: no-till farming. As a good practice that has blessed our soils, it was not free of sin. Problems originated from its wrong employment and the overuse of certain means made pioneers realize that not everything has been said before, since no-till farming by itself was not enough to meet the challenge of saving our soils. This is how the concept of "no-till farming" was shaped, by implying that within this system there are other things to take into consideration, namely: tillage, presence of living soils throughout the year, smart diversification of crops in time and space, and integrated pests and nutrients management. That is the system that, currently, many people are calling regenerative agriculture or simply sustainable agriculture, suggesting that we are all talking about the same thing.

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Through all of these years, through rights and wrongs, the no-till farming system worked as a guardian of the soils of the entire country, joined by an increasing number of farmers that were convinced that it was the right path to take good care of their most important resource. Meanwhile, Aapresid started to get involved in the currently most discussed concept of "soil health", that can be somewhat defined as the ability of soil to sustain productivity, diversity and environmental services of terrestrial ecosystems. Within these human-managed systems, soil health can only be maintained, increased or recovered through the employment of sustainable management practices. It is interesting to acknowledge that these definitions emerged in mid-2008, when Argentina already had nearly 80% of the land under no-till farming method, meaning that almost 80% of the soil was starting the path toward soil recovery. Argentina was, silently, already leading the sustainable agroindustrial production.

Nowadays, we feel the need to disclose what we did and how we did it. To tell about this network system that strengthens everybody's knowledge and that enables means and solutions, such as no-till farming, to spread across every territory that needs it. Thus, Aapresid could also stand as a benchmark regarding cover crops, these crops have as a purpose promoting soil health and providing ecosystem services, purposes that were hard enough to include in rotations, not by an absurd farmers' denial, but because conditions were not suitable, neither we had the necessary knowledge to implement, sustain and complete them once they had finished their period of "service". This status was only obtained through a great joint of public and private participants that believed in this networking that created bridges and heals wounds.

Behind the relation between networks and participants, we must not lose sight of the major responsible that made all of this food sustainable production became possible: the farmer. Said farmer had a key main role in no-till farming employment at the time, it is the same farmer that nowadays feels the weight of multiple factors preventing them from producing and caring, as if that dichotomy had to coexist as an eternal antagonism, when it clearly does not. Producing should imply caring. Producing necessarily involves caring, because if not, we would not be producing, but wasting that much important resource that is the soil. Aapresid's mission is to spread this message to every corner of the world, and that is why the message in this magazine goes beyond idiomatic limits and invites us all to join this great mission: to be the guardians of the soil.

Rodrigo Rosso Manager of Prospectiva - Aapresid.

STAFF RESPONSIBLE EDITOR

Dorrego 1639 Piso 2 Of. A Tel. 0341 426 0745/46 aapresid@aapresid.org.ar www.aapresid.org.ar

Chair of Aapresid Marcelo Torres

DEPUTY DIRECTOR OF PROSPECTIVA

DEPUTY ASSISTANT DIRECTOR

Paola Díaz

Carolina Meiller

EXECUTIVE EDITOR

Carla Biasutti

INTERNATIONAL PROGRAM

Rodrigo Rosso

Elisabeth Pereyra

Mailén Saluzzio Federico Ulrich

WRITING AND EDITING

COMMUNICATION

Antonella Fiore

Victoria Cappiello

AAPRESID CERTIFICATIONS

Matilde Gobbo

Juan Pablo Costa

CONTENT MANAGEMENT

Florencia Cappiello

Rocío Belda

María Eugenia Magnelli

Elina Ribot

Eugenia Moreno

Magalí Asencio PROOFREADING AND EDITING

Agustina Vacchina

ADMINISTRATION AND FINANCE

Lucía Cuffia

Delfina Sanchez

Cristián Verna

TRANSLATION Laura Cudugnello

MARKETING Lucía Ceccarelli

Vanesa Távara Dana Camelis María Laura Torrisi

CHACRAS SYSTEM

Mariana López

LAYOUT AND DESIGN

Andrés Madías

Daniela Moscatello

Daiana Fiorenza

Suyai Almirón

Samanta Salleras

Chiara Scola

Magalí Gutiérrez

Julieta Voltattorni

Lina Bosaz COORDINATING MANAGER

Ramiro Garfagnoli

PERSONNEL MANAGEMENT

Tomás Coyos

Solene Mirá

Macarena Vallejos

PROSPECTIVE PROGRAM

PEST MANAGEMENT NETWORK

INSTITUTIONAL RELATIONS

Rodrigo Rosso

Eugenia Niccia

Lucía Muñoz

Antonella Fiore

Juan Cruz Tibaldi

Federico Rolle

Ignacio Dellagiovanna

María Victoria Ribecca

STRATEGIC PROJECTS María Florencia Accame

RESOURCES GENERATION

AAPRESID REGIONALS Matías D’Ortona

María Florencia Moresco

Matías Troiano

Virginia Cerantola

SECRETARY

Alejandro Fresneda

Facundo Pace

Karen Crumenauers

The publication of personal opinions expressed by collaborators and interviewees does not imply said opinions are necessarily shared by the Aapresid management. The total or partial reproduction of the contents without the express authorization of the publisher is prohibited.

INSTITUTIONAL

Argentina benefited from its local condition in front of farmers from all around the world. Our country was the headquarters of the annual Global Farmers Network meeting. Nearly 80 farmers from five continents came to the country to exchange experiences and explore establishments with cutting-edge technology. They also participated on a day trip to AgroUranga to see "the Aapresid model" taking action.

Global Farmer Network (GFN) was initiated in 2000 in Des Moines - Iowa, United States, where it is also headquartered. Its mission is to "amplify farmers' voices promoting commerce, technology, sustainable agriculture, economic growth and food security".

By Lic. Mailén Saluzzio y María Cecilia Ginés International Program - Aapresid

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It currently consists of 239 members representing six continents and 62 countries. The Network identifies, involves and supports global leader farmers that can work with other farmers to innovate, promote and lead, as full interested parties, the work being developed on compensating the global breach regarding food and nutritional security in a sustainable manner. To accomplish this objective, GFN is fostering numerous actions including the arrangement of an annual event called "GFN Roundtable". It is a training communication program and round

tables that gather farmers from all around the world to debate about topical subjects on food, fibers and energy production. Every year, nearly 15 farmer leaders from different regions and productive environments are summoned to engage in this meeting and become members of the network. Since 2006, Argentine farmers and Aapresid associates have been invited, in several opportunities, to participate in the GFN Roundtable. Pilu Giraudo, Pedro Vigneau, Edgard Ramírez, Nicolas Bronzovich, Tomás Oesterheld and Jorge López Menéndez were some of the associates that had the chance to be a part of this experience. In 2020, after his involvement, Oesterheld emphasized that, besides the personal learning that entails coming into contact with multiple global agricultural methods, participating in this event is important for the

institution "as it allows Aapresid members to provide their own outlook on developing subjects, namely, no-till farming and its role regarding climate change mitigation and adaptation, one of the main axes of this gathering and the one that most concerns farmers worldwide”. GFN is a strategic institution for Aapresid's international connection, that is why the international program created a proposal for Argentina to be the host of the event and worked collaboratively in its organization. According to Aapresid's honorary president, GFN member and team member of the program, Pilu Giraudo, "the advances Argentina has made in relation to production sustainability, with the dissemination of environmental protective practices, such as no-till farming–nowadays reaching 90% of the cultivated area in our country–motivated the election of our country as base for the event."

GFN Roundtable in Argentina From 5 to 11 of February, Argentina was the host of this annual event with the motto: "Mobilizing GFN to support a resilient agrifood system". It was a mass onsite event which, for the first time, included the participation of almost 80 farmers members of the network from more than 30 countries. Although this annual event is usually directed to only 14 or 15 farmers joining every year, Global Farmer Network's Board of Directors decided the Argentine event to be opened to a mass member attendance. "It was a huge honor that they decided to change the format, that they valued the

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proposal of all members meeting personally, and that they chose Argentina as headquarters of this first big gathering since the network was founded. After this experience, we hope to be able to hold a mass GFN event every two years," claimed Pilu Giraudo. The agenda included professional panels, training sessions, visits to farming establishments and the sector’s industries and institutions. Farmers aimed at learning no-till farming-based systems, biotechnology advances, production scales, and how Argentine farmers are organized.

As part of the tour, the party visited the AgroUranga establishment, which is the name of the farm and it is part of Aapresid's regional office in Pergamino-Colón. They were received by the Chair of Aapresid, David Roggero, the Vice President, Marcelo Torres, and the President of AgroUranga, Ignacio Uranga. "As farmers, we have a vital role in proving the virtues of these systems capable of satisfying increasingly food demands and, at the same time, contributing to climate change mitigation. We farmers should lead the scaling of conservation agriculture, and we are committed to work together alongside science and technology," began Marcelo Torres.

Farmers aimed at learning no-till farming-based systems, biotechnology advances, production scales, and how Argentine farmers are organized.

The tour included a review on no-till farming system axes in charge of Cesar Belloso; and concluded with a visit to the processing plant of pisingallo corn, chickpea, pea and lentil. The closure of the tour was led by María Cecilia Ginés, manager of Aapresid's Programa Internacional, who highlighted the potential for conservation agriculture to progress globally and be a part of the solution to climate change: "Farmers must lead this model's integration and adaptation processes in their own regions. In Aapresid we know how this process begins, therefore we can provide knowledge and learn together to reduce implementation breach.”

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Throughout 30 years of experience, Aapresid developed programs to support and guide farmers who look for producing in a more sustainable manner by employing no-till farming. "However, back at the beginning and to one of the great mottos of GFN events, the farmer is the leader and main character of the path toward conservation agriculture," ended Ginés. The GFN Roundtable schedule also included a visit to Marcelo and Carlos Testa establishment, in Pergamino city, Buenos Aires. During the tour, they provided details on performed activities, showed how agricultural drones operate, explained Bayer's PRO Carbono program–which seeks to

expand field productivity and increase carbon sequestration in soil by employing sustainable agricultural practices–and showed how to use Phytobac tool for sustainable managing of phytosanitary effluents. Aapresid associates proved how soil protection and biodiversity as a production tool are a crucial part of the productive system. "In our farm we have a healthy cultivated area, we create biological corridors and protect our hives. We want society to be conscious that it is possible to conduct intensive agriculture and protect the ecosystem at the same time," Marcelo stated.

To finish with the weekly schedule, there was a meeting to address cooperation possibilities and conjoint work between farmers and scientists. Present in this meeting were Juan José Bahillo, Secretary of Agriculture, Fernando Camargo, Argentine representative of the Inter-American Institute for Cooperation on Agriculture (IICA), and Carlos Cherniak, Permanent Representative of Argentina to FAO. On his part, Camargo invited the attending farmers to join the assembly that will represent the Americas' agriculture, and will also exhibit their sustainable practices in the next United Nation Climate Change Conference (COP 28), at the end of the year.

An opportunity for Argentina Throughout the schedule and meetings with farmers and institutions, GFN members had the chance to exchange experiences and learn about the sustainable production model promoted in Argentina, which is based on proper agricultural practices, innovation and digitalization. The event was an enormous opportunity for Argentina to share not only its capability for technological innovation, but also its network organization that includes farmers, researchers, input suppliers, farm machinery, agtechs, and others. In this context, Aapresid’s associate and Deputy Director of Programa Prospectiva, Nicolás Bronzovich, explained that in other countries it can be observed the lack of multidisciplinary cooperative networks, while in Argentina they are naturally incorporated. "A First World farmer asked us for Aapresid to teach him how to work collaboratively among peers. For us, being able to assist in both technical and network matters–in a collaborative and multidisciplinary way–was to me the most impressive, and gave me great pride," he said.

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Similarly, Pilu Giraudo added: "It is satisfactory to know that every farmer of the global network, public and private referents, chose our production systems as the most accurate, for our technology and collaborative system, for our networking abilities." However, she acknowledged that there are still many challenges ahead and we must keep on working to reach a better path together. Farmers around the world face the same issues and doubts, how to produce in a sustainable manner while protecting the environment, and how to manage a new agriculture. Likewise, they

are eager to share experiences, knowledge and learning, and they are ready to take action side by side as the main characters of transformation and leading development itself. Aapresid has a multidisciplinary team committed to learning together and working collaboratively to boost sustainable agriculture globally. That is why we recognize the importance of having an area within the institution that promotes connections with farmers around the world and carries Aapresid's mission to an international extent.

INSTITUTIONAL CIENCIA Y AGRO

Redefining innovation: different means for current agrifood systems During the past few years, there were substantial changes in the farming sector that are redefining innovation. Climate change, traceability, digital technology, and environmental impact demand to be addressed differently in order to ensure agrifood security in an ever-changing world.

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In the past years, new technology innovation and development within the farming sector in Latin America have evolved. Following World War II, when many European countries supplying food were devastated, innovation and development purposes were directed to increase food supply, by enhancing productivity through genetic improvement alongside farming practices, a process that was later known as Green Revolution.

According to a report by the Inter-American Institute for Cooperation on Agriculture (IICA), this was mainly possible due to the conjoint work of national agricultural research institutes (INIAs), such as the National Agricultural Technology Institute (INTA in Spanish) and international centers, that organized scientific and technological actions toward that common goal, and provide institutional support for the development of technologies employed by farmers. As a result, Latin America improved its food security and increased its participation in global farming production, becoming one of the main net food exporting regions.

In recent years, there were substantial changes in the farming sector, which was inevitably reflected in the way innovation was conducted. According to the report, these changes happened over several aspects.

yield losses forecasted in this context between 2006 and 2050 required R&D investments of around $187 billion and $1,384 billion ARS. Currently, new technologies need to face emerging environmental and social crises.

On the one hand, the concept of "agrifood systems" was consolidated–more complex than that of agriculture–which includes new participants and necessities related to nonagricultural activities, along with environmental and nutritional concerns throughout the chain under concepts like "farm-to-fork", developed and promoted by the European Union.

Similarly, while environmental issues were not considered relevant during post-war periods, nowadays sustainability is being pondered, focusing mostly on biodiversity, natural resources conservation and climate change.

On the other hand, worldwide climate change threatening productivity: compensating for crop

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"These matters set out a great challenge for institutions like INTA, because in addition to adding complexity by involving climate change as a key variable in whatever innovation or development, this impact should be analyzed

from an agrifood system perspective, meaning from primary production, through industry to consumers," said Marcelo Torres, Chair of the Argentine No till Farmers Association (Aapresid). He was summoned to participate as an Argentine referent at the Regional Dialogue on Science, Technology and Innovation in Agrifood Systems of Latin America and the Caribbean before 2030 issues, that took place at IICA Headquarters in Costa Rica in the past April. Back to IICA's report, another great change within the sector is accompanied by the broadening of the science development spectrum, with strong advances in biology, information and communications technology (ICT), artificial intelligence, nanotechnology, robotics and

Currently, new technologies need to face emerging environmental and social crises.

engineering, areas that are currently providing precision and reliability to process. "These tools are decision-making allies and offer real support for a less environmental footprint in productive models, such as the Argentinian one, and help connecting with consumers," Torres added.

The last one of these big changes is related to the private sector, which became the main responsible for innovation in agrifood systems, and gained attention alongside the increasing significance of biology, genetics, computing and other sciences.

Institutional support, science, funding and farmers prominence Facing this new scenario, Torres claimed that it is necessary to strengthen the institutional system in order for the sector to evolve regarding innovation manners. "The dialogue in Costa Rica founded the bases to keep enhancing strategical matters within the agrifood sector in America, including them in the global agenda, and identifying potential areas of cooperative work," he declared. In the same way, it will be crucial to stop being led by "beliefs" and rely on science and technology to inspire innovation. "At the meeting in Costa Rica, organizations such as IICA and World Bank evidenced a firm decision thereon," the Chair of Aapresid added. Alternatively, he assured that "when those employing new technologies join as a part of the innovation process, it is enhanced." By seizing new developments, they assist in generating and spreading those solutions that actually respond to the needs of the system.

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"One clear example is that of Argentine growers, global leaders in employing process technologies, such as No-Till Farming, which currently involves 90% of Argentinian cultivated fields. This is not so visible in other countries, where producers are at the bottom of the process, acting as participants adopting new developments attributed to other areas or participants," Torres emphasized. That is why an evolution of these models would unlock new opportunities as a country. Finally, he addressed the need to examine innovation funding systems closely, asserting that "farmers have a crucial role; although just as they contribute to economic resources and necessary investments for the development of new technologies, they should be able to be more involved in systems management."

CIENCIA Y AGRO INSTITUTIONAL

Aapresid touring across Europe The Chair of Aapresid participated in important international forums and events taking place in different countries across Europe. We will disclose every detail and result that this thriving journey left.

In June 2023, several events were held, in which some Aapresid's representatives participated actively, with the purpose of conveying farmers' voices to international forums. The main objective was drawing attention to conservation agriculture in the fight against climate change, and broadening the innovation network with farmers as protagonists. The Chair of Aapresid, Marcelo Torres, traveled from Argentina to take over the proposed agenda during the tour. Likewise, María Cecilia Ginés, consultant of Aapresid's international program, participated in the events held in Amsterdam and Bonn. By: Agr. Engr. María Eugenia Magnelli To Prospective Program Aapresid

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In this article we will issue the primary activities that were conducted, along with the outcomes of this international tour.

Bonn Policy Dialogue Luncheon - Bonn, Germany From 5 to 15 June, the Bonn Climate Change Conference took place, an event gathering signatories from the United Nations Framework Convention on Climate Change (UNFCCC), previous to COP 28 transpiring in Dubai by the end of 2023. One of the parallel events occurring during the closure of the conference was the Dialogue organized by Coalition of Action for Soil Health (CA4SH), a coalition aiming at improving soil health globally by addressing critical implementation, monitoring, policy, and public and private investments barriers that constrain farmers from adopting and scaling healthy practices. As a member of the coalition, Aapresid was invited to represent the project that has been carried

out within the framework of a panel that covered case studies on numerous countries about soil health protection and improvement. During the presentation, Marcelo shared Aapresid's mission, and mentioned how he works in promoting sustainable production systems with the farmer as main character. The panel also involved the participation of Jack Hannam, President of the British Society of Soil Science, and Christina Munzer, department for Agriculture, Fisheries and Forestry of the Australian government. Upon the closure, there was a space for questions in which Marcelo explained fervently the path of innovation prompted by Argentine farmers.

World Soybean Research Conference 11 - Vienna, Austria

From 18 to 22 June, the 11° World Soybean Research Conference (WSRC11) took place in Vienna, Austria. This meaningful scientific event is organized every four or five years in different parts of the world, and offers a global perspective on critical matters the industry and the soybean

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sector are facing. The first WSRC was held in the United States in 1975, and the Vienna edition was the first in Europe. The objective of the WSRC is promoting investigation, and encouraging interaction and

debate among the worldwide soybean-related community, as it is a highly important crop for food and fodder supply. Marcelo Torres, Chair of Aapresid, was invited to participate as keynote speaker at the plenary session named "Soybean in Agricultural Systems". His presentation was targeted on providing a holistic view on soybean crops, and outlining its key role concerning the development of a considerate environmental farming production.

"We bet on low environmental impact production models, capable of supporting and increasing food, fibers and energies production within a climate change context".

Our Chair's paramount transmitted messages were: "We are working in a real transformation of productive models basing ourselves on facts. We bet on low environmental impact production models, capable of supporting and increasing food, fibers and energies production within a climate change context. We highlight the fundamental principles of these productive systems that goes beyond ordinary headlines, such as intensification and diversification of crop rotation in no-till farming, along with a balanced nutritional strategy and integrated pest management. We underlined the true change we are performing, always networking side by side with science and technology, and the farmer as a protagonist."

Greentech - Amsterdam, the Netherlands Greentech is known as the most important international showcase in the horticulture sector. Specialists and professionals from all around the world convened there to share knowledge, innovation and the best practices in the universe of horticultural technology. Marcelo and Cecilia had the chance to attend, and they were accompanied by Ignacio Elena, Agricultural advisor of the Netherlands Embassy in Argentina, and Simkje Kruiderink, Regional Coordinator for South America at the Ministry of Agriculture, Nature and Food Quality in the Netherlands. They engaged in some activities including a tour across the stands of the numerous pavilions, a visit to the panels "Cultivation planning with

algorithms" and "Integrated pest management for healthy plants", and a networking lunch sponsored by the Ministry of Agriculture, Nature and Food Quality of the Netherlands. During the trip, the team had conversations with Dutch agricultural attachés in several countries, focused on Argentinian farming production models. Moreover, there were considered possibilities of cooperation with the Ministry of Agriculture, Nature and Food Quality of the Netherlands, such as the potential participation in the congress of Aapresid and in agricultural technical tours, in addition to the support in the development of relations with European associates.

Visit to Wageningen University - Wageningen, Kingdom of the Netherlands Wageningen University and Research (WUR) is a prestigious public institution and center of research located in the Kingdom of the Netherlands. It is focused specifically on life sciences, concentrating on agricultural, technical and engineering subjects. During their visit to WUR, Marcelo Torres, María Cecilia Ginés, Ignacio Elena and Simkje

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Kruiderink were received by Ria Hulsman, manager of international cooperation with Latin America at WUR. The team was able to attend meetings with multiple experts with the purpose of boosting connections between the University and Aapresid, keeping sustainability as the connecting thread of numerous conversations.

From left to right: Ria Hulsman, María Cecilia Ginés, Marcelo Torres, Marianna Sigmund Schultze, Sinead O’Keeffe, Simkje Kruiderink and Ignacio Elena.

From left to right: Ab Veldhuizen, Marcelo Torres, Simkje Kruiderink and Ignacio Elena.

SCIENCE AND AGRIBUSINESS

Agriculture based on artificial intelligence From real-time spatio-temporal detection on fields, through climate and cultivation models, to mechanized robots automating farming practices, artificial intelligence is revolutionizing agriculture. A review on the latest trends in pursuit of a more sustainable intensive agriculture.

By Hugo Permingeat Technical Prospective Committee Aapresid

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Agriculture is at the height of a fourth revolution, especially in relation to sustainable production intensification purposes. Digital technology, and notably artificial intelligence (AI), will be major components in this new revolution. The term AI was coined for the first time by John McCarthy in 1956 and, in a rational approach, defines it as the system that automates intelligent behavior or acquires intelligence over time by employing computer programming, and provides rational results to conduct specific tasks without much human intervention. From real-time spatio-temporal detection on fields, through climate and cultivation models, to mechanized robots automating farming practices and operations, AI has the potential to revolutionize workforce and agriculture-based decisions. To make this happen, basic advances are required not only as regards AI technology, but also in the way workflows are designed and improved in order to satisfy the needs of the actors involved in agriculture. Fulfilling the promise of an Agriculture 4.0 enabled by AI is only possible with a transdisciplinary scientific effort, thoroughly coordinated and concerted (Kalyanaraman et al., 2022).

The usage of AI in sustainable agriculture has the potential to transform certain aspects like images detection for mapping and output forecasting, skilled and unskilled manpower, yield increasement and farmers decisions support. To achieve a more sustainable agriculture, AI is being employed in a variety of ways, among which we can mention environmental monitoring, automatic climate control in greenhouses, crop quality monitoring, livestock management, predictive analytics and integrated farm management systems. AI products are highly demanded as a means to obtain information on farming practices, digital diagnostics on plant health, remote sensing and irrigation management solutions. AI tools provide access to optimization of drip irrigation systems, technological assistance on precision agriculture, inclusion of the Internet of Things (IoT) to evaluate water, humidity and fertilizers requirements, artificial neural network (ANN) to predict basic agricultural products prices, machine learning and robotics (Bhagat et al., 2022).

These authors analyzed, classified and made use of keywords to highlight articles and reviews delivering the following results: there is a rising academic interest in the field of AI used in sustainable agriculture with a radical improvement since 2019. China, the United States and Australia are leaders in producing the best literary works. Some claimed that there is a big potential for AI application to ensure sustainability, particularly in output forecasting, crop protection, climate control, crop genetic monitoring and supply chain products. Shaikh et al. (2022) also ensured that, as it progresses, AI is continuously finding ways to involve itself in agriculture. These authors consider smart farming (SF)–commonly known as Agriculture 4.0–as a set of current technologies and advances capable of improving crop production and reducing water and energy usage. This will be possible owing to the integration of environmental sensors and forecasting technologies. Farming operations can be adjusted to achieve major productivity with less natural resources due to new introduced capabilities by smart farming.

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Thus, the digital farming revolution will transform agriculture by enhancing efficiency, sustainability, inclusion and transparency. However, to be able to benefit from these capabilities, technologies must be integrated in the farming industry at a major scale. There are still several issues to be solved, such as compatibility, heterogeneity, and massive data management and processing. Agriculture 4.0 should generate, transfer and process data correctly and at the same time protect itself against cyber-attacks. Mobile and wireless technologies are intrinsically related by dint of IoT, and they would probably respond to many agricultural issues. The same authors differentiate the concept of SF from that of precision agriculture. "Smart farming is a technology that bases its implementation in the use of AI and IoT in cyber-physical farm management." SF addresses many problems related to crop production as it enables monitoring climate component changes, soil features, humidity, etc. Precision Agriculture (PA) is a new globally used concept to increase productivity, reduce work time and ensure efficient fertilizer and irrigation management. AI in agriculture helps farmers improve their abilities, in addition to changing target agriculture to achieve higher yields and better quality by employing less resources. SF makes use of technologies–such as sensors and networks, unmanned aircraft systems (UAS), satellite images, IoT, and drones–in order to reduce

farmers' workload and boost productivity. SF is a crop management approach allowing farmers to control geographical and temporal diversity in agriculture, likewise intrusion threats and realtime data monitoring. Chemical sensors for pH, wind, rain, temperature, humidity and auditory are widely used in modern agricultural operations. Van Hilten y Wolfert (2022) analyzes the usage of 5G connectivity in agriculture and agrifood chains as a means for AI usage. The authors suggest that the application of 5G to agriculture is in early stages. However, they emphasized five major benefits: 5G connectivity allows the creation 1 of cyber management systems in the agrifood industry.

5G activated for IoT could boost its usage in agriculture.

Offers higher connection speed, volume, processing power with up-to-date 3 computing and less latency to improve smart farming.

Real-time supply chain management 4 enhances food quality control and waste reduction.

Leads to the appearance of self-sufficient farming.

Moreover, authors identify cases in which technology is implemented in concept testing. Most of them can be found among agriculture and livestock and are focused on monitoring, usually combined with big data analysis. Currently, totally self-farming processes are only to be expected from the medium and long-term. Furthermore, it can be observed a major focus in individual commercial decision-making rather than in optimization within a region, namely, joint management of scarce resources such as water. Current projects are frequently motivated by public research and telecommunication companies in cooperation with end users–

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farmers, suppliers and food processors. Innovation is generally prompted by bottlenecks that different actors undergo in the agrifood system. In some cases, bottlenecks are high labor costs or the need of a larger labor productivity to raise farming incomes; while in other cases, environmental pressures can act as catalysts for the development and adoption of new communication technologies. AI in agriculture is becoming so transcendent that there are already scientific magazines specialized on the subject. One example is the magazine "Artificial Intelligence in Agriculture", which recently published a review on IoT for agriculture. In said article, Xu et al. (2022) described 5 essentially related technologies that make generation and data flow possible. These include: a) sensor perception–for monitoring; b) information transmission–with node systems and wireless; c) information processing; d) radio frequency; and d) remote sensing technologies. Once again, applications that authors find relevant include irrigation systems linked to efficient water usage, environmental conditions monitoring for crop growth and development, AI-controlled machinery, crop and livestock information monitoring, and quality and traceability of agrifood products.

In a recent review, drones are mentioned as preferred remote sensing technologies, a matter of great importance because of multiple advantages compared with other technologies. For example, they provide high quality and resolution images, and high information transfer availability and speed. Moreover, they serve as instruments for product application in a scheduled and precise manner (Rejeb et al., 2022). Energy in agriculture is another feature where AI can make significant contributions, both for rural electrification and the functioning of the above mentioned systems. The usage of AI in farming energy systems is also a fundamental technology for the setting up of smart farms, as it generates early alerts which can assist in farming production improvement. Farm electrification and computerization promoted even further IoT development and created agricultural energy internet (AEI) based on IoT in agriculture and IoT in energy. It is assumed that with renewable energies and agriculture integration, carbon emissions will be reduced. AI and AEI warnings will become one of the most impressive technologies in agricultural computerization (Fu and Yang, 2022).

In a recent article, Kalyanaraman et al. (2022) described the creation of AgAID Institute–a transdisciplinary and multi-institutional AI research institute. The institute centers its efforts in providing AI solutions for special crops farming where issues related to water availability, climate variability, extreme weather and labor shortage are notably pronounced. The institute is founded on three great intellectual and unifying principles:

Adoption as the first principle in AI design, to remove barriers regarding AI technologies adoption in application-related farming matters.

Adaptability to changing environments and multiple scales, a skill our methods encode inherently.

Amplifying human skills and machine efficiency through a close human-AI partnership and increasing automation. This is crucial to close workforce breaches and improve machinery efficiency, which lead to a whole greater than the sum of its parts.

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Thus, AgAID Institute carries out a variety of activities that include the use of AI farming applications–such as test benches to develop innovative technologies and workflows; sets the technological bases for a climatically smart farming; works as a nexus for collaborative, transdisciplinary and culturally inclusive learning; prepares next generation's workforce for the race between farming and AI technologies; and facilitates adoption and transfer of both farming and AI technologies (Kalyanaraman et al., 2022).

REFERENCES

In the last decade, AI-based scientific and technological production has expanded considerably, generating improvements in all productive processes and value chains. This article centers on agrifood systems—including some recent reviews—that, besides laying out advances and describing benefits, promotes actions devoted to make the adoption of these disruptive technologies more efficient in order to boost the all-time-longed-for sustainable, responsible and productive agricultural intensification.

Check the references by entering www.aapresid.org.ar/blog/revista-aapresid-n-214

SCIENCE AND AGRIBUSINESS

Safe and sound soils Soil health is a concept with multiple dimensions. A journey to meet authors and investigations about a subject that affects us all.

Por:Hugo Permingeat By Permingeat, H. Technical Prospective Comité de Prospectiva Committee Aapresid Técnica Aapresid

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Soils have always been an essential part of terrestrial ecosystems, sustaining its functions and biodiversity. Moreover, they are crucial for food production, water storage and cleanliness, carbon accumulation, climate regulation, energy protection, raw material supply and critical infrastructure support (Harris et al., 2022). Soil health is usually used as a synonym for terms such as "soil quality" and "soil fertility"; although some people prefer “health” because soil is considered a living system. It is about a multidimensional concept referring to the soil's capacity to serve as an ecosystem for plants and animals’ sustainability, while supporting human activities like agriculture. Decades of evidence have demonstrated farming and environmental benefits of agricultural practices–cover crops, no or zero tillage and diversified crop rotation. These healthy soil practices are aligned with conservation agriculture principles: maintain vegetation covers alive, reduce disturbances, and diversify crop rotations (Atwood et al., 2022).

Soil health is usually used as a synonym for terms such as "soil quality" and "soil fertility"; although some people prefer “health” because soil is considered a living system.

One of the challenges is to develop more effective methods of employing a metaphor like "soil health" with monitoring and managing purposes so all interested parties–farmers, technicians, political decision makers, etc.–easily understand and adopt it by considering underlying scientific facts. Harris et al. (2022) studies that the conventional approach to describe "soil health" was focused on simple in situ measures based on key variable points (P mineral, microorganismnutrient interactions). In the last decades, these methods evolved on different levels of finesse and complexity, motivated, partly, by a wave of innovations in metagenomics, sequencing and computing. Current technology innovations improve the abilities to carry out not only soil features measure, but also a constant or regular monitoring able to help farmers on the season's decision-making and at a greater scale. However,

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these measures per se or combined do not allow health comprehensive assessment of the entire soil system. These authors propose a paradigmatic shift of this atomize approach within state variables. Said shift is directed to a study of the entire system by critically exploring connection, complexity and purpose of the elements, while realizing that it is the only way emergent properties signals can be detected. In this analysis, Harris et al. (2022) suggests a whole system approach to assess soil health based on a new hierarchical organization structure of the soil system. This context includes: interrelated life signs–communities, DNA, metagenomic; functions–transformations that occur, thermodynamic efficiency; complexity– community interrelations, communal trophic structures; and emergency–recovering responses before frequent disturbances. It also

reflects a growing organization hierarchy and ecosystem development, which could be known characteristics in ecological succession. The authors advise that these parameters should provide information to identify soil as a system, and how the integration of physical, chemical, and biological properties of the soil are combined in a complex and connected manner from which emergent properties and functions arise. Similarly, Wood and Blankinship (2022) described the importance in providing a practical framework to turn soil health into a more efficient delimitation object. They assert that all soil health actions should be directionally accurate, quantitatively linked to results, should have a well-resolved results-related functional form, and should prove whether potential shifts due to management are big enough so as to lead to expected outcomes. Most of the research on soil health is focused at field scale, although many of soil health benefits are collected at other scales. That is why there is the need to innovate through new actions. Currently, there is an ongoing investigation about soil methods that could contribute with unique knowledge on soil health in the future. Enhancing soil health knowledge field needs the contribution of other disciplines like mathematics, statistics and economy, in order to help develop new analysis methods and data aggregation to unravel the effect of changes in soil properties and turn it into positive results for the environment and agriculture.

Said shift is directed to a study of the entire system by critically exploring connection, complexity and purpose of the elements, while realizing that it is the only way emergent properties signals can be detected.

Atwood et al. (2022) presents a framework on how the crops protection industry can boost soil health through innovation systems development, and at the same time, target soil health results by direct impact in soil or by allowing practices fostering soil health results. Said approach could lead to integrated and intersectoral farming solutions that accomplish farming, environmental and economic objectives. Many available chemical, biological and genetic solutions for soil protection maximize shortterm benefits to avoid pest damages during the season, but do not aim for long-term soil health results. Nevertheless, discussions about the relation between crop protection innovation and soil health are unusual. One exception can be weeds management, for two reasons: returning to tillage for herbicide-resistant weeds management would reduce soil health; and practices encouraging it could contribute positively to weeds management–cover crops. These authors claim that it is possible to imagine a future in which soil’s ecological interactions are protected and promoted by crop protection innovations, improving soil health and preventing pests damage in crops economically. This evolution on crop protection is also supported by remarkable advances in complementary disciplines like digital technology. New imagebased diagnosis tools, new equipment for precision agriculture, and upgraded forecasting algorithms for abiotic and biotic stress issue specific crop protection programs. Transitioning into this future would help for a wider vision of society toward sustainability in all sectors, manifested in international policies and initiatives such as the European Green Deal and the

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United Nations 2030 Agenda for Sustainable Development. Through the setting-up of the Coalition of Action for Soil Health (CA4SH), the crop protection industry, and other interested parties, expressed their intentions to collaborate for barriers removal in sustainable farming systems promoting soil health. Shifting toward a crop protection system that encourages soil health is a not-so-explored lane. This will require pest management methods compatible with specific soil health practices that do not damage the functional capacity of soil communities. Atwood et al. (2022) introduces three key research and development priorities that crop protection community should pursue: 1) innovative products and application methods that avoid or reduce soil health impact; 2) innovative products– sole or combined with plant genetics–that profit from soil functions and communities to refine pests management and diseases, and/or biogeochemical nutrient cycles, and reduce input usage; 3) products innovation enabling management practices that benefit soil health and lower compensations. Achieving these prospects require a fourth type of innovation: 4) developing new soil health evaluation methods and field tests throughout the R&D StageGate process of crop protection.

A recent review of Dessureault-Rompre (2022) broadened the attention put on soil health through the use of phytotechnology capable of restoring, conserving and regenerating multiple functions and ecosystemic services provided by the soil, especially within agroecosystem contexts. The author demonstrates the importance of root features and functions for soil restoration, and emphasizes that plants and roots diversity, alongside perpetuity, are main elements for an efficient process of soil restoration. She introduces a phytotechnology tool box which includes three bases for agroecosystem restoration: farming practices and land management, rhizosphere engineering, and ecological intensification. This paper highlights the importance in developing specific restoration strategies based on phytotechnologies originated from roots function and rhizosphere processes understanding. In practical actions, cover crops, intercropping and living mulches are well-known and studied farming practices. Through plant roots and rhizosphere functioning mechanisms, these practices improve soil structure, carbon capture, N and P fertility, soil biodiversity, and erosion reduction. Multiple species used for cover crops are linked to sustainable farming practices because they contribute to the raising

Transitioning into this future would help for a wider vision of society toward sustainability in all sectors, manifested in international policies and initiatives such as the European Green Deal and the United Nations 2030 Agenda for Sustainable Development.

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of N retention and weeds elimination. In addition to soil properties, cover crop diversity also enhances roots and covers architectonic features. Competence among plant roots in communities rich in species can increase carbon storage in soil's rhizosphere, soil aggregates composition by size, and nutrients. Meanwhile, rhizosphere engineering is the manipulation of one or more of the three rhizosphere axes–soil, biota, plant roots–to emulate nature's evolving mutual beneficial interactions among soils, plants and soil organisms. Many studies were focused in soil modification, inoculation and plants metabolic engineering in order to boost crops productivity and their resilience against biotic and abiotic stress. Thus, it was proved that compost and biocarbon enhance soil's physical, chemical and biological conditions, which holds a positive impact on crop productivity. Mycorrhizae and bacteria inoculation responsible for plant growth is related with fine biological properties of the rhizosphere under stress by drought, as well as fine growing conditions of marginal lands.

Finally, ecological intensification was suggested as an approach to integrate ecological processes in land management practices to upgrade ecosystem render services and mitigate anthropogenic contributions. Ecological intensification aims at combining nature and agriculture for the designing of multifunctional agroecosystems, sustainable by and within nature. Targeting soil restoration, integration of ecological intensification principles enables the expansion of opportunities to enhance farm-scale or agroecosystem biodiversity (DessureaultRompre, 2022). Finally, there is ongoing basic research about soil methods that can provide unique knowledge on soil health for the future, and contribute to said research through several fields of study. The concepts these authors mention encourage technology integration for the search of a common farming and environment sustainable objective over the rational use of the soil, and by raising awareness about the importance in maintaining its health.

REFERENCES

Check the references by entering: www.aapresid.org.ar/blog/revista-aapresid-n-215

BIOECONOMY

A journey across Cuyo region’s bioeconomy Chacra Valor Agregado, alongside farmers and Aapresid's companies, organized a tour across Mendoza province. With bioeconomy as a banner, the backpack returned full of knowledge, ideas and business opportunities motivating this region. We disclose everything in this article.

By Agustín C. Torriglia

Technical development manager Chacra AVO

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Aapresid's farm AVO, meaning value-added at origin–from now on Chacra AVO–organized a tour across Mendoza province aimed at meeting the region's reality, especially biomass opportunities to generate added value and development. It was a three-day trip–30,31 of March, 1st of April– that included a visit to several productions and a workshop, which involved the participation of professionals in different areas.

Chacra AVO members, LODO and CIRCA staff in space Lodo.

National outlook on bioeconomy One of the first activities took place at Lodo's site, where Fernando Vilella, Alejandro Gennari, Andres Cohen from Circular Carbon (CIRCA), and Magdalena Pesce from Wines of Argentina (WoFa), lectured on bioeconomy, environmental footprint, judicial and institutional water framework in Cuyo, and strategy and communication of Argentinian wine. During the gathering, it was highlighted the power of bioeconomy as a strong means to promote resilient territorial development, and one that is

currently portraying a clear geopolitical issue due to a request of an ambitious land-use planning. Bioeconomy is the result of scientific knowledge applied to biomass, and represents one step forward toward economical biologization. Since biomass transportation is evidencing logistic and cost difficulties, bioeconomy seeks to address the need to transform and process biomass at a regional extent. This entails a vertical integration involving numerous actors and disciplines

throughout the chain, creating a beneficial bioeconomic ecosystem.

Bioeconomy’s most prominent paths are agricultural ecological intensification, ecosystem services, biorefineries and bioproducts, value chain improvement, biotechnology and sustainable use of biodiversity.

Environmental footprints and life cycle assessment (LCA)

Completion of workshop at LODO. From left to right: Agustín Torriglia, Maximiliano Bordas, Jorge Gambale, Fernando Vilella, Andres Cohen, Magdalena Pesce, Martin Sanchez and Alejandro Gennari.

Professionals in charge of the lectures defined carbon credits as a "marketable certificate representing the reduction of a ton of carbon dioxide equivalent emissions (T CO2eq) in the atmosphere". According to their explanations, these transactions originated from a verified and certified project by international and qualified standards. Thus, all projects must abide by principles and benchmarks rigorously audited.

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General principles leading the process are: relevance, completism, consistency, precision, transparency, conservatism and additionality. Underlined among the steps for issuing carbon credits are:

1. Selection of methodology: for example, VM0042 methodology for projects aiming at organic carbon storage in soil and/or CO2, CH4 and N20 net emissions reduction.

2 Description and introduction of the project. 3 Validation of the project's description.

4 Verification of emissions reduction. 5 Issuing carbon credits. Meanwhile, LCA is considered as a methodology tool that enables to determine and quantify current and potential environmental impact of a product or system throughout its life cycle.

Verificación de la reducción de emisiones.

Walnut tree production from within During Thursday 30th afternoon, the group visited Qnuuts establishment that has a walnut tree plantation and a processing plant in Uco Valley. As regards walnut production in our country, the following points stand out: Argentine provinces leading walnut production are Mendoza, San Juan, La Rioja, Catamarca, Neuquén and Río Negro. Argentine walnut cultivated area has been increasing in recent years. 1,9274 hectares of walnut trees were registered during season 2020-2021. Most cultivated walnut variety in Argentina is Chandler, followed by Serr, Hartley and Howard. Argentina’s primary destination of walnut exports is the United States, followed by Europe and Asia.

The company has a cultivated area of more than 500 hectares distributed among several farms in the provinces of San Juan, La Rioja, Catamarca and Mendoza. In Uco Valley there are 126 hectares. Qnuuts produces more than 330 tons of walnut and the entire cycle is conducted in its own facilities: cultivating, mechanical harvesting, hulling, drying, sizing, and packing. In relation to the harvesting timeline, the Chandler variety hull starts to split between late March and the first days of April. The harvest consists of making the tree vibrate, sweeping the fruits into windrows and collecting them. As soon as hulls begin to split it is time for regular fruit picking, although not more than two or three in a threeweek span. Taking care of it, the fruit is sent in harvest trolleys to the industrial plant. The company is certified in Good Manufacturing Practices (GMP) and in food inoculation (HACCP), and currently its production is exported to countries in Europe, Asia and Latin America.

Santa Mónica farm Another interesting location the group visited was Santa Mónica farm, a property of Grupo General Deheza S.A. (AGD in Spanish). The farm has a total of 1,744 hectares, and is located in Jocolí city, 45km north from Mendoza city. The land is 587masl and it is a flat area with deep and alluvial soils. The texture varies from clay loam to sandy loam. These soils present high levels of salinity, so they need to be washed for a proper farming development.

To the moment, the company has 768 hectares planted with almond trees, all of them Spanish varieties with hard shells–Guara, Felisia, Marinada, Penta and Vairo. Around 460 hectares are planted with almond trees grafted in rootstocks of Nemaguard or Nemared (peach tree), and the rest in rootstocks of Garfinem (a peach-almond tree hybrid), and all irrigation water is from drilling. They started with a plantation framework of 6x4, and now they are seeking more intensive systems with frameworks of 3.5x1.25 in order to achieve around 2000 plants/ha.

Chacra AVO members in almond plantation - AGD

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Harvesting is mechanized through a shaker, a vibrator machine, and mechanical harvesters for picking up the fruit. Production is nearly 2000kg of unshelled almonds and the plantation has a lifespan of approximately 25 years.

In said farm, which is 2800m2, there is an almond shelling and selection plant with a process capability of 1200kg/hr.

Nutrilanda The Argentinian company Nutrilanda is a specialist in agricultural biotechnology, and researches, develops and trades innovative solutions in order to enhance crops growth. On that basis, they produce biofertilizers and biostimulants based on the selection and transformation of both the agricultural and meat industry's residues.

The group visited the company and participated in a lecture in charge of Maximiliano Bordas, a member of Chacra AVO and partner of Nutrilanda, who explained about ongoing projects, types of sources they use, the process, and growth and potentiality of the biofertilizers market.

Compost in Campo Lavalle S.A. establishment.

Closing remarks ● The roving workshop was useful for learning different productive realities and new business opportunities in another region in which partners do not operate. ● Three overall objectives pursued by Chacra were addressed: biobusinesses alternative assessment, carbon monetization possibilities assessment, and the conveying and promoting of what was learned through different means. ● For objective number 2–seeking biobusiness investment alternatives–it was known first-hand a biofertilizer alternative production by using various sources, which accomplished a product for both intensive and extensive production. Actually, several members showed interest in validating the product in their own productions. The proposal about a biofertilizer production plant would be reachable for areas with a broad green belt. ● For objective number 3–value capture through carbon credits feasibility assessment–the presentation of a professional consultant in sustainable matters helped us to answer some questions, such as what are carbon credits, which are the methodologies, what is the additionality principle, and the steps to follow when starting a project of similar nature. ● Argentina has a great opportunity to achieve a balanced territorial development by embracing the bioeconomy paradigm. There are many unsatisfied markets for which we could be great suppliers, by owning one of the productions with less environmental footprint, and by escalating the pyramid upward greater specificity and value products that involve biomass as a key raw material.

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About Chacra AVO Chacra AVO consists of 19 farmers and companies distributed across the provinces of Buenos Aires, Santa Fe, Córdoba and Mendoza, and aims at "business alternative assessments considering bioeconomy as an axis to address social issues related to climate change." Among its workstreams, we can emphasize the following: Learning about business niches, by identifying opportunities of niche businesses, and also learning about necessary tools for investment projects assessment. Seeking biobusiness alternatives, meaning initiatives based on biomass and seeking value capture and generation. For example: biofertilizers as regional business models, plant proteins, silvopastoral systems, among others. Assessing feasibility of value capture through Carbon credits, learning about the carbon market, and initiating certification and monetization process. Conveying and promoting what has been learned. Generating didactic content for members and general public in order to obtain a broader review of the subject. Succeed is based on the premise that the more we are, the greater the possibilities of success will be. To address all different workstreams, Chacra carries out several monthly workshops throughout the year–on site and online. The visit to Mendoza is framed within these kinds of actions, which enables people to meet and learn about every regional reality with the purpose of discovering new opportunities to generate added value and progress. If you are interested to know more about Chacra AVO, you can contact their technical development administrator (RTD in Spanish), Agustín Torriglia (Cell: +5493584369100 - Email: agutorriglia@gmail.com).

CROP MANAGEMENT

Gold-worth-residues Crop residues are crucial for farming system sustainability. Both sorghum and corn are great stubble generators. This article will analyze residue quantities and decomposition in both crops growing under different management practices.

By Gonzalo Parra, Lucas Borras y Brenda L. Gambin

Research Institute of Agricultural Sciences of Rosario (IICAR in Spanish), Faculty of Agricultural Sciences at the National University of Rosario (UNR in Spanish). Brenda L. Gambin - Agronomy Department, Iowa State University (bgambin@iastate.edu)

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Crop residues quantity and quality are highly important for farming systems sustainability. Direct and indirect benefits of surface residues over crop production were extensively documented (Jayaraman & Dalal, 2022). Sorghum is a crop that has lost ground compared with corn. The main cause lies in investment disparity between the two crops (Parra et al., 2020). However, sorghum is completely effective

in residue production, which makes it a very interesting crop for carbon sequestration within the system, particularly in restrictive or degraded environments. This article analyzed comparatively the residual quantity and decomposition in corn and sorghum crops growing under different farming methods– mainly seeding date and nitrogen management.

Materials and methods Tests were performed in Campo Experimental Villarino in Zavalla city, Santa Fe province, for two years–2017/2018 and 2019/2020. Treatments

included three different seeding dates–Oct., Nov., Dec–, three levels of applied N in 2017 (0, 100 and 200 kg N ha-1), and three levels of

water management in 2019–dryland, limited and irrigation. The cultivation analysis was based on two commercial materials–corn and sorghum–, both of mostly known maturity. Plants density was 8 and 20 pl m-2 for corn and sorghum respectively. Each year-management combination was considered a different environment (Table 1), where it was evaluated: residue or stubble quantities–on 1m2 of harvested plants and output deduction estimations–, quality–through C-N relation and soluble carbohydrates amount–, and decomposition following Burgess et al.

Environment

Year

Water condition

proceedings (2002). As a no-till farming method was conducted, residues were permanently kept on the soil's surface. Data was analyzed by nonlinear mixed-effects models, using nlraa package in R (Miguez, 2022). Adjusted models assessed crop and time as fixed effects, while environment was assessed as a random effect.

Applied N Seeding date

Rainfall Sept. - April

Yield ± EE (T ha-1)

(kg ha-1)

(mm)

Corn

Sorghum

2017

Dryland

05-Oct

100

283

8.9 ±0.8

7.7 ±0.6

2017

Dryland

05-Oct

200

283

10.5 ±1.8

9.2 ±0.3

III

2017

Dryland

05-Oct

300

283

11.7 ±1.7

9.9 ±0.8

2017

Dryland

06-Nov

100

246

9.8 ±1.8

7.3 ±0.8

2017

Dryland

06-Nov

200

246

10.8 ±1.0

8.7 ±1.0

2017

Dryland

06-Nov

300

246

11.2 ±2.1

8.9 ±0.4

VII

2017

Dryland

27-Dec

100

317

7.8 ±1.0

6.1 ±0.9

VIII

2017

Dryland

27-Dec

200

317

8.9 ±1.4

5.8 ±0.7

2017

Dryland

27-Dec

300

317

9.2 ±2.0

5.9 ±0.4

2019

Deficit

08-Nov/20-Nov

100

289

6.5 ±0.8

3.4 ±1.6

2019

Dryland

08-Nov/20-Nov

100

417

9.8 ±1.4

4.6 ±1.1

XII

2019

Irrigation

08-Nov/20-Nov

100

702

10.6 ±0.7

6.7 ±2.7

Table 1. Different environments experimentally generated to compare the quantity and decomposition of corn and sorghum residues.

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Results Sorghum crop yields were 2.6t ha-1 less than corn, but left 2.2t ha-1 more stubbles in the surface compared with similarly managed corn through every environment (Table 2). Nevertheless, decomposition rate was 2kg ha-1 day-1 higher in sorghum compared with corn (Table 2). These differences resulted in similar residue amounts

for both crops at 90 days since harvesting (Figure 1). At the beginning, sorghum stubble showed less C-N relation and a major amount of soluble carbohydrates than corn, although the differences were not statistically meaningful (Table 2).

Crop

Residue (Tn ha-1)

Decomposition rate (kg ha-1 day-1)

C-N

Soluble carbohydrates (%)

Corn

9,8

-2,6

94,4

11,8

Sorghum

-4,6

82,3

18,7

P value

<0.001

0,15

0,39

Table 2. Starting residues amount, residue decomposition rate during 90 days, C-N relation, and starting soluble carbohydrate percentage in residues for corn and sorghum under different managements. P value indicates considerable differences–p<0.05–between crops.

Figure 1. Time-based residue amount since harvesting for several corn crops (red) and sorghum (blue) with similar growing conditions. The line indicates the model adjustment through environments.

Both residues’ amount and decomposition were modified by management conditions. Stubble amounts in sorghum increased due to late seeding dates, while in corn it was observed an optimal response with a significant drop on residue amounts on December seeding period (Figure 2A). N showed a positive impact on the amount of stubble in corn, but not in sorghum (Figure 2B). For both crops, decomposition rate was reduced because of late seeding dates (Figure 2C), and rose owing to applied N dosage independently of the seeding date (Figure 2D).

Furthermore, late seeding dates affected notably the starting amount of the residue's soluble carbohydrates (Figure 3A), and the rising of N dosage reduced the starting C-N relation of the residue (Figure 3B). Decomposition rate was positively linked with soluble carbohydrates amounts in stubble (r2=0.40 and 0.75 for corn and sorghum respectively; p<0.001; Figure 3C), and closely linked to C-N relation only in corn (r2=0.73; p<0.001; Figure 3D). Low temperatures as a result of late seeding also contributed to a slower residue decomposition in both crops (r2=0.20; p<0.05).

Figure 2. Starting residue amount in corn (red) and sorghum (blue) for different seeding dates (A) and applied N (B). Residue's decomposition rate in corn and sorghum for different seeding dates (C) and applied N (D).

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Figure 3. (A) Residue starting soluble carbohydrates in corn (red) and sorghum (blue) for different seeding dates. (B) Residue starting C-N relation in corn and sorghum for different levels of applied N (B). Residue's decomposition rate in corn and sorghum based on starting soluble carbohydrates content (C), and starting residue's C-N relation (D).

Conclusions Under similar managements and environments, sorghum crop leaves more stubble than corn, but it decomposes faster. This greater decomposition would be mainly connected to a larger soluble carbohydrates amount in sorghum residues. Management affects residues’ amount and decomposition through changes in its starting quality. Corn late seeding dates leave less residue in the surface, a feature with high consequences in carbon intake within current production

REFERENCES

systems based on these dates. Its quality and time of the year, however, contribute to a slower decomposition. The results indicate the importance in knowing the residue's quantity and quality, being the differences between crops an interesting feature to take into account, depending on residue's management context and specific objectives.

Check the references by entering: www.aapresid.org.ar/blog/revista-aapresid-n-218

CROP NUTRITION

Biological innovation to optimize wheat production Ping-pong of questions and answers with Aapresid's biological nutrition network, and the first test results on biofertilizers and biostimulants application in wheat season 2022/23.

By Agr. Eng. Dr. Martin Torres Duggan¹ and Agr. Eng. M. Florencia Accame² ¹ Tecnoagro consultant and technical coordinator of Red de Nutrición Biológica (RNB). ² Technical Zone Coordinator - Sistema Chacras Aapresid.

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Bioinputs usage in general and biostimulants technologies in particular are growing notably at regional and global extents, and the trend is also visible in Argentina. However, technology responsible management requires, on the one hand, learning the features of its formulations, and on the other hand, its positioning within the agricultural field–what effects they have on crops, soil and/or environment. Despite the great expansion of Argentine bioinputs and biostimulants, there is not much scientific information concerning their impact

under extensive production conditions, neither many actions have been carried out on extension actions that enable the farmer to learn about these technologies, environmental benefits, or their role to improve crop yield and/or quality. To know more about this matter and the scope of Aapresid's biological nutrition network (RNB in Spanish), which is celebrating one-year old, we share this back-and-forth of questions and answers, which also includes the test results on biofertilizers and biostimulants application on wheat for season 2022/23.

1. Why a biological nutrition network? The main goal or vision of RNB is to contribute and promote knowledge about features and benefits of biostimulants usage–and biofertilizers at a lower level–such as input technology within

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Argentine agroecosystems. Although current focus is upon grain extensive production systems, in the Chaco-Pampa region the project is not exclusive to that geographic region.

2. How does RNB work? RNB is framed within the Programa Sistema Chacras (INTA-Aapresid agreement), which analyzes farmer's demands, and with the involvement of professionals, consultants and other collaborators who analyze process and/or input technologies, provides solutions to problems that stem from farmers demand (Figure 1).

Figure 1. Schematic diagram of the functioning of Sistema Chacras (INTA-Aapresid agreement).

3. What is RNB purpose and which activities does it conduct? It is important to clarify that the term "network" does not refer to "testing", but a collaborative network, or a knowledge and exchange generation network, i.e., “hub”. Thus, even though experiments conducted on farmers’ lands are part of RNB initiatives, its target is not experimental information generation.

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RNB's main goal or objective for medium or longterm–vision–is to reduce information breach acquired by farmers, regarding features and benefits of biostimulants usage on sustainable crop management in Argentina.

The actions performed by the RNB are adjusted and modified every year according to the support of sponsor companies and emerging doubts on each season. Although questions and learning change every season, their vision–what is expected from RNB in the future–remains unchanged. As regards the experimentation component conducted on farmers’ lands, during season 2022/23, ten experiments on wheat were carried out–biological treatments applied on seeds or in foliage–and they are settled in 16 soybean and corn tests.

4. What is the difference between biofertilizers and biostimulants? Despite the terms "biofertilizer" and "biostimulant" are currently being reviewed, mostly due to regulatory aspects, it is important to have a clear understanding on the difference between fertilizers in general–including biofertilizers–and biostimulants. Fertilizers are sources of essential nutrients for plants. Therefore, products such as urea, DAP, MAP, TSP, SSP, phosphate rock, etc. are examples of fertilizers commonly known by farmers. These products are analyzed because of their nutrient content, which is the basis for making fertilizer dosages always following a diagnostic model. Particularly, in the case of biofertilizers, the activity of a certain microorganism provides the nutrient and acts as a dominant ingredient or active–or bioactive–constituent. Some biofertilizer examples are inoculants applied on seeds to stimulate biological nitrogen fixation (BNF) in legumes, namely Rhizobium sp., Bradyrhizobium sp., etc.

However, from current academic outlook, biostimulants contain compounds and/or organisms that, when applied over crops mainly under abiotic stress, enhance features like yield, quality, nutrient usage efficiency, among others. Similarly, recent regulations being considered for products registering deem at a high order the term "biostimulant", and within this category are included products that are usually classified as "biofertilizers". Hence, formulations with Azospirillum sp., Pseudomonas sp. that have plant growth-promoting rhizobacteria (PGPR) effects–major portion of application to seeds– are addressed as biostimulants. Nevertheless, formulations that contain free amino acids or peptides, botanical extracts, or phytohormones, alone or combined with added nutrients, are the products which were normally addressed as "biostimulants".

Regardless of conceptual differences between fertilizers and biostimulants, it is relevant to remember that biostimulants are to be evaluated no by the percentage of bioactive elements and/or components they hold, but by their functions within the agroecosystem. This requires an integral approach, where crops’ soil health and nutrition, namely fertilization, does not represent a practice to be replaced or substituted, but to be complemented. That is, paired with biostimulation in order to improve

crop productivity under abiotic stress, a feature often happening among extensive production systems, as the one in Pampa region which is dominated by highly variable rainfed and climate systems–high frequency of extreme events such as hydric stress, heatwaves, and late or early frosts. In addition, soil salinity and alkalinity–also considered as abiotic stress–that prevail in many regions, can be partially mitigated by the usage of biostimulants applied to seeds.

5. What were the test results on biofertilizers and biostimulants application on wheat for season 2022/23? Although "La Niña", a very serious event, affected crop evolution significantly in most productive regions, it was possible to collect the tests and generate preliminary data, which should be carefully assessed owing to a very first year of testing, and within an extreme climate context– prevalence of drought, heatwaves, late frosts, etc. Figure 2 presents the geographical distribution of those locations in which biological treatments on wheat crops were evaluated. The tests were conducted on farmers' fields, ensuring treatment repetitions availability and plot monitoring at different moments during the crop cycle.

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Figure 2. Geographical distribution of experimental sites for application to seeds (A) or to foliage (B) in wheat crops on season 2022/23.

Both the average yield and the outcome of the farmer's applied fertilization varied significantly depending on the experimental site. Thus, a distinct treatment effect was found in two of the 6 sites–e.g. 33% of response frequency–that is shown in Figure 3. In Corral de Bustos, Córdoba province, where outputs were low, the outcome to the farmer's technology (TP; conventional fertilization) was 760kg/ha, stemmed especially from added nitrogen and phosphorus. Average low output at this site was linked to severe frosts affecting ears of wheat’s blooming stages, as precipitation were not particularly low during the cycle–109mm from seeding to harvest–when compared with the ones at the Paraná site–159mm. The latter had a TP (conventional fertilization) response of 1477kg/ha.

It is worth to highlight that in sites where statistically significant effects were perceived, the obtained output of biological treated wheat–e.g., without the grower's fertilization–was notably lower and similar to the absolute unfertilized control plot. As regards combined technology, meaning TP+biological treatments, in Corral de Bustos the output within these treatments was similar or lower than the one obtained by using TP. In contrast, in Paraná, fertilizers and biostimulants combined application enabled to reach similar or higher output depending on the applied product, in comparison with obtained yields solely with grower's regular fertilization. The results from these first tests analyzing biostimulants-based treatments on foliage are consistent with those reported on international

Figure 3. Average wheat yield (kg/ha) according to biological treatment application to foliage. TP: farmer's technology. TB: biological technology TC refers to combined technologies (TP+foliage biostimulants). The numbers indicate different commercial formulations.

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literature, which indicates that in prevalent nutrient-deficient soils the adding of foliage biostimulant products do not allow to sustain yields. Although in some cases it is possible to generate synergies between fertilization and biostimulation, meaning higher yields when pairing fertilization and biostimulation technologies. It is also possible to improve the quality of the harvested product, namely micronutrient and/or protein contents, when certain types of biostimulants are applied.

On the contrary, none of the sites employing seed treatments showed statistically significant effects at 5%. Meaning that variability within treatments was greater than that imposed by treatments. Treatments included 13 or 14 combined fertilization technologies–grower's regular management–and the application of a wide range of biostimulants formulations, some of them with added nutrients or bioactive compound-enriched fertilizers, such as microorganisms like bacteria, fungi, etc.

6. What were the paramount learnings of RNB's first year and how it is planning season 2023/24?

One major learning and common denominator within most of Aapresid's thematic networks is climate vulnerability. Season 2022/23 revealed the extreme of a climate anomaly, and that should teach us that the best we could do to face climate variability is to incorporate more resilient production systems. Part of said resilience is built upon healthier soils and crops, and both fertilization and biostimulants usage still have much to contribute to that matter. The year 2023 focused on increasing communications and extension activities.

RNB, just like the rest of the thematic networks within the program, has an exclusive magazine. The first edition of this article will include further details regarding wheat results than the ones in this edition, besides including a bibliography and information of interest for the farmer in relation to biological nutrition on extensive crops.

CROP NUTRITION

Adjusting corn nutrition over predecessor Vicia villosa Chacra VINPA analyzed the response of nitrogen fertilization on corn over predecessor Vicia Villosa in highly potential environments. Two types of management were assessed: termination with chemical drying, and rolling for fodder usage.

By Alfonso Cerrotta¹ and Magali Gutiérrez² ¹ Technical development manager at Chacra Valles Irrigados Norpatagónicos (VINPA), Aapresid's Chacras program. ² Zonal technical coordinator in Aapresid's Chacras program.

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North Patagonia region has a unique edaphoclimatic atmosphere for the development of a wide range of crops, so rotations can vary considerably. Despite said biodiversity, corn is an ever-present crop and it is deep-rooted within this region's history. In last years, Chacra VINPA's farmers have solidly incorporated Vicia Villosa as a service crop prior corn. In some cases, vicia is used as fodder feed both for direct consumption and in roll form. Even in establishments with more diversified and intensified rotations, vicia is employed among 25% and 30% in the entire agricultural area. This is mostly because its positive contribution to soil health and its plasticity regarding seeding dates (Vanzolini et al., 2016).

The adoption of vicia in rotations is generating systematic contributions of N to the soil, which lead us to re-evaluate N responses to corn. Collected experiences amid seasons 20172020 showed a response saturation to a dose of 250kg N/ha (Gutiérrez, 2022). However, with vicia's systemic contribution of N within the last 5 years, it is logical to foresee a lower saturation dose, as long as it is the same hydric, nutritional, germplasm and plant density management. If these elements change, responses will likewise change, the same as economic optimum dose, which not only depends on biological response, but also on grain-fertilizer prices relation. Moreover, there is the question about the effect of using vicia as fodder in the system, particularly in relation to early spring produced biomass.

The target of this study is to know the results of nitrogen fertilization in corn with predecessor Vicia villosa under two types of management: termination with chemical drying, and rolling prior corn sowing within a mixed system using cover crops as fodder.

The target of this study is to know the results of nitrogen fertilization in corn with predecessor Vicia villosa under two types of management. Methodology: Tests on corn were performed at Kaitaco establishment, located 45km away from General Conesa city, in Río Negro province. For the test, a water balance was carried out on the plot, weighing daily risks and precipitations provided by the establishment. Moreover, it was considered the ETo from a local weather station data, and crop coefficient was measured through satellite images using Calera et al. (2016) methodology. Corn was sowed with 80% of available water, it received 31mm of precipitation and 1134mm of irrigation during the entire crop cycle. On 18 February, 2022, vicia was sowed subsequently to corn with a 19cm row distance arrangement. In late autumn, grazing of self-grown

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wheat was performed on the plot. On October 11, a production of 4,300kg DM/ha of vicia was measured. A section of the plot of 200m * 400m was cut and rolled, and another adjacent strip of 100m * 400m was chemically dried. Previous to sowing, an analysis on nitrate was conducted, which showed N levels of 103.7kg/ha (0-60cm), 6 ppm of Pdisp (0-60cm) and 0.68 ppm of Zn. On October 24th, perpendicularly to vicia treatments it was sowed KM 3916 hybrid, with a density of 95,000 seeds/ha, 0.7m row distance arrangement and 40kg of MAP/ha. In the same direction, different nitrogen doses in the form of urea were applied in two moments: post-sowing and V2-4. The treatments involved increasing doses of urea in the control crop ranging from

0kg to 900kg of urea/ha at intervals of 150kg. Treatment application width was 10m, the working range of the fertilizer machine. Similarly, the treatment of 300kg of urea/ha was analyzed at several application points: the total of V4 vs 150kg in post-sowing, and 150kg in V4. At the intersection of nitrogen fertilization treatments with two types of vicia management, 3 sampling points of 3.5m2 were randomly established, with no lack of plants caused by faults. Ripen ears of corn were harvested, following the measurement of yield, moisture, yield components–number of ears of corn, grains per ear of corn, and P1000–, and hectolitre

This analysis was based on the following details: Price ratio (N/grain)= 10:1 N price: applied on field Grain net price: -25% commercialization expenses Dollar official exchange: ARS $366 Excluding opportunity cost (interest rate) Rolling manufacture cost: ARS $7000 Conversion efficiency roll:meat: 17:1

weight. Yield was expressed in kg/ha and was adjusted to commercial moisture content (14.5%). Relative performance was measured based on the medium value of the higher yield treatment. Moreover, a sensitivity analysis was conducted to assess net income variations of rolling production practices, and own-farm consumption vs. vicia's chemical drying. The equation applied in the analysis was: ∆ NI = GI meat - Roll costs - Extra N costs - Yield loss

Outcomes and discussions The average output of the test was 13,981kg/ ha, with a minimum of 6,951kg and a maximum of 17,915kg/ha. Average output of rolled vicia treatment was 13,213kg/ha, while average output on chemical drying treatment was 14,828kg/ha. Vicia's Nitrogen contribution is broadly analyzed (Enrico et al. 2020). On average, it is stated that biomass on vicia presents 3% of N in aboveground and belowground biomass, of which nearly 70% comes from BNF, and the rest is absorbed by the

soil in the form of nitrate. Considering an above and belowground biomass partition of 9:1, vicia's chemical drying of an aboveground biomass production of 4,300kg DM/ha would leave 129kg N/ha higher than when extracted completely in roll form. It needs to be emphasized that not everything is biological fixation of N, there is a part that is derived from the soil absorption of N-NO3.

Figure 1. Test plot water balance on season 22-23 at Kaitaco establishment (Conesa).

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The water balance in the plot proved that irrigation covered the crop's water demand, maintaining useful water above the stress threshold during the entire cycle (Figure 1). This stress threshold means a minimum level of the needed water in the profile so the crop can maintain its transpiration and not lose yield. The most adjusted point of the balance was found during the last week of December, and coincided with the last vegetative stage of the crop–V10-V12 (Figure 1). Blooming and grain filling were developed at high levels of useful water. Moreover, NDVI images in critical periods enabled to establish that the testing sector was very homogeneous, without overt irrigation or soil problems (Figure 2).

Figure 2. NDVI from January 11, Pv1 corn fertilization testing on season 22-23 at Kaitaco (Conesa) establishment.

In absolute terms, cover crop chemical drying performed better than the rolled ones under every N treatment, except in the case of 150kg urea dose where outputs were equal.

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A response to added nitrogen with notable differences among vicia managements was observed (Figure 3). Both vicia management and nitrogen fertilization treatments were the main components of yield variation, along with management and N treatments interaction, which was also significant. This interaction was reflected in a minor difference between vicia treatments as urea dose was increased, reaching its maximum levels at the 750kg urea treatment, where no differences were observed among vicia treatments (Figure 3). Whereas yield difference among control crops without N was the highest.

A response to added nitrogen with notable differences among vicia managements was observed.

Figure 3. Average yield per test fertilization treatment in Pv1 corn during season 22-23 at Kaitaco (Conesa) establishment. Different letters mean a significant difference by Fisher DMS test (p<0.05).

Figure 4. Average yield in 300kg/ha urea treatments of fertilization test in corn applied in two moments (PS: postsowing). Different letters mean a significant difference by Fisher DMS test (p<0.05).

Moreover, there were differences among urea application moments. Rolled cover crops, where 300kg of urea were applied post-sowing, exceeded an equal-dose treatment divided in 2 (post-sowing and V4), a situation not observed in chemical drying of cover crops (Figure 4). These results indicated that in situations where cover crops were used as fodder, there could be an early N deficiency if no application is conducted at the beginning of the cycle.

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Figure 5. N absorbed by unfertilized control crops with a relation of 25kg absorption of N per ton of yield. Different letters mean a significant difference by Fisher DMS test (p<0.05).

The comparison between control crop yields under two managements of vicia showed a difference of 3,350kg/ha. Considering a 25kg quantity of N absorbed per ton of yield (García, 2005; Setinoyo et al. 2010), the yield was expressed in terms of unfertilized crop absorption of N. Corn on chemical dried vicia absorbed 85kg more N than on rolled vicia (Figure 5). In a simplified way, this is an approximation of vicia's contribution of N to chemical drying treatments.

The response threshold is defined as the value above which nutrient availability does not become a limiting factor. When modeling the N response under two cover crops managements, and using a relative yield of 95% as the response threshold, it was observed that N response with dried cover crop is saturated with about 125kg less of N than rolled cover crop (Figure 6). The slope of the response curve was lower for chemical dried crop,

and reached a plateau somewhat higher than with rolled cover crop (Figure 7). These results can be owing to the incidence of different beneficial effects of cover crops and N contributions, such as water retention, infiltrations, lower losses of moisture by evaporation, biological activity, less erosion, among other factors.

Figure 6. Curve of corn yield response to total N contribution (Soil+Fertilizer). Yield was expressed in relative yield to one of 16,515kg/ha. 95% was considered the response threshold.

Rolled cover crop was effective depending on current fertilizer, grain and meat price scenarios, leaving aside other fixated variables (Table 1). However, because of high volatility presented within the macroeconomic context, it is necessary to conduct an up-to-date analysis by the time to make cover crop management decisions.

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In this analysis, it is necessary to highlight the extra yield that the corn crop showed when it had coverage compared to the situation without coverage, regardless of the nitrogen dose.

Figure 7. Crop during establishment (left) and in V4 (right) over chemical drying treatment on vicia during season 22-23 at Kaitaco (Conesa) establishment.

Conversely, it is necessary to emphasize the yield bonus exhibited by the crop when provided with a cover, in comparison with the situation without one, independently of N dosage. This analysis showed a yield bonus of 550kg. This evidence shows how interesting it would be to make the most of vicia cover crop as fodder, but allowing vicia a growing period prior to corn planting, if possible. It is that, although there will not be N contributions to the system, there will be benefits from the cover crop per se.

rhizodepositions (Berenstecher, 2023), a situation that could occur in any of vicia management practices here analyzed. In addition, this study produced the N response from a corn yield perspective, but it did not focus on N dynamics in soil. The usage of Nan indicator (Reussi Calvo et al., 2014) at the beginning and end of the crop cycle could be a good tool for future studies, and thus it can provide ideas for N contributions by mineralization during cultivation, and how much is left for successor crops.

Another variable that was not studied in this case but it is relevant, is the beneficial effect of vicia in the following stages of crop rotations. There is not only a gradual and slow nitrate release because of residue mineralization, but also carbon and high valuable exudates contribution by

Table 1. Sensitivity analysis of net income per hectare over rolled vicia management vs. chemically dried. ( ) Current scenery. Red- Yellow- Light Green- Dark Green: activity's net income scale from minor to major.

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Conclusions Vicia cover crop generates nitrogen contributions to the system by biological fixation, which becomes a part of the above and belowground biomass, and it is released when biomass decomposes. The use of vicia cover crop as fodder, such as roll manufacturing, produces kg of livestock meat indirectly, but exports most of said N, leaving a negative balance in soil. On the contrary, cover crop chemical drying generated more than 125 kg of N contributions to the successor crop, in this case corn. Moreover, chemical drying exhibited a saturation dose of 270 kg less of Urea, and the saturation dose yield was 550kg higher than rolled vicia. These outcomes suggest that fodder usage was a fruitful practice under current circumstances. In terms of economic viability, the decision to choose drying or rolling should consider price scenarios on fertilizer, corn and livestock products; in this case, that of live weight per kilogram of a calf.

REFERENCES

Check the references by entering: www.aapresid.org.ar/blog/revista-aapresid-n-222

CROP NUTRITION

The keys to close the breach

Nutrition and soil management are two crucial means in the search for reducing yield breaches. But, how much does each of them explain? A study to review the keys to help us close the breach.

By Reussi Calvo, N.I. ¹,²*; Studdert, G.A.¹; García, F.O.¹,³

¹ Faculty of Agricultural Sciences, National University of Mar del Plata. ² CONICET. ³ Consultant. Email: nahuelreussicalvo@mdp.edu.ar * Paper presented at Simposio Fertilidad 2023 "Al gran suelo argentino ¡salud!"

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Argentina's main extensive crop yields and, therefore, nutrients demand, have increased in the past 20 years. Growth rate of overall grain production reached 4.17M t per year due to a larger participation of corn crops within the farming area (Satorre & Andrade, 2021). However, there is a breach between current and attainable rainfed yields. Said breaches range from 35% to 50% (Andrade, J. personal communication) and answer to multiple reasons, from soil health and its management to crop management practices.

levels in soil in Pampa region and, consequently, nutrients natural supply. Thus, according to the soil's type and texture, currently, only 50% of OM original level is present (Sainz Rozas et al., 2011). Historically, Argentina’s crops nutrient balance has been negative, meaning that the removal on grain exceeds application. This caused nutrient breaches, defined as the difference between applied nutrients and those necessary to meet attainable yields, subject to different scales based on area, plot and/or environment (Figure 1).

In addition to a low usage of fertilizers, the absence of pasture rotations and/or rotation decrease in grasses frequency, produced a significant reduction of organic matter (OM)

Figure 1. Conceptual schema of the relation between nutrient supply and demand in Argentina in the last 50 years. The stars indicate, as an example, nutrient breaches for different areas in the country (Draw up on the basis of Sainz Rozas et al., 2011; and Satorre & Andrade, 2021).

The outcome to deficient nutrients application– generally nitrogen (N), phosphorus (P), sulfur (S)–, varies according to soil health status (Figure 2). There are three soil health scenarios that could notably affect nutrient responses, and could be related to years-long continuous cropping. Scenario 1: Good edaphic health soils; nutrient application could improve yields, and nutrient breach could be linked to nutrient availability. In this case, nutrient usage efficiency is maximum. Scenario 2: Medium or partially deteriorated soils–compaction; nutrient application could contribute to the decline of negative effects of root growth in poor conditions, and reduce yield breaches. For this to happen, it is necessary to take action to reverse/resolve soil health issues non-related to chemical fertilization–controlled traffic farming, grass rotations, cover crops. Scenario 3: Severely degraded soils; by erosion, compaction, salinization, biodiversity loss, and others, where nutrient application would have a low impact in reducing yield breach.

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Figure 2. Conceptual schema of the relation between crops yield according to soil fertilization levels with different soil health status (Draw up from Tittonell & Giller, 2012).

On the basis of Figures 1 and 2 emerge the following question: does nutrient breach increase with the years of agriculture? Based upon the analysis of generated data by long-term tests carried out by the Unidad Integrada Balcarce (Studdert, 2017), it was estimated that nutrients breach was linearly increased with the years of continuous cropping–from 0 to 15 years–on an average rate of 2.8% year-1 in conventional tillage systems, and 4.4% year-1 in no-till farming (Figure 3). This behavior could be associated with Scenario 1 (Figure 2) because during the studied period no levels of physical degradation that could limit response possibility were reached. Nonetheless, on the same tests, aggregate stability–physical health soil indicator–declined

exponentially with the years of agriculture, especially in the first 5 years (Figure 4). Numerous studies proved an increase in yield response to added nutrients with the rising of the years of agriculture (Studdert, 2017; Ernst et al., 2018). Moreover, Ernst et al. (2016) and Tourn et al. (2019) observed greater damage in the soil's physical quality as a result of the increasing number of annual crops in rotations. This would denote that, in the long-term, Scenario 1 could become Scenario 2–and in the worst case, Scenario 3–if nutrients application is not paired with other management practices that avoid soils' physical health worsening.

Figure 3. Nutrients breach according to the years of agriculture under no-till farming and conventional tillage. Draw up with long-term tests-Unidad Integrada Balcarce (Formulated from Studdert, 2017).

Figure 4. Aggregates stability based on the years of agriculture under no-till farming and conventional tillage (Source: Domínguez et al., 2008).

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Currently, most cultivated plots in Argentina exhibit more than 15 years of agriculture (possible Scenario 2, Figure 2). Under these conditions, studies based on tests conducted in different areas of the country indicated that a balanced nutrition with N, P and S benefits from 15% to 47% in soybean, corn or wheat yields (Figure 5). However, as mentioned, crop nutrient balances were historically negative in Argentina. To address this situation, recent studies suggest that the replenishment of N, P and S levels held by grain crops would enable to reduce possible

yield breaches. This is based on validations at plot production levels to corn (n=44), wheat (n=50) and soybean (n=117), where a comparison was made between current nutrients dose employed by the grower, and replenishing fertilization. Average yield response was 15% in corn, 22% in wheat and 13% in soybean (Monzón, personal communication).

Figure 5. Fertilization with N, P, S, NPS and NPS with micronutrients (Complete) contributions to different crops yield (Source: Plant Nutrition Network, CREA South Santa Fe province, CREA South Santa Fe-IPNI-Nutrien).

Similarly, in Southeast Córdoba, long-term tests with replenishing fertilization, together with a change in rotations toward corn-wheat/soybean intensification (Gudelj et al., 2017), indicate an increasement in fertilized treatment yields over time, contributing to possible breach reduction after 10 years of balanced nutrition (Figure 6). Nevertheless, the question emerging is if this is only owing to a nutritional direct effect. From the same studies collected data, it was established that nutrition by replenishing, in addition to a more proper rotation, tended to improve aggregates stability over time (Figure 7), which would be explained by the enhancing of soil organic matter content. This indicates that, to a Scenario

2 situation, yield breach reduction is mainly explained by the combined effect of nutrients availability and edaphic health strengthening. Other authors resolved that nutrient application– particularly N–in an optimal agronomic dose enables not only maximize grain yields and residue contributions, but also fixate more Carbon. While excessive doses–above economic optimal– lead to negative externalities, such as less carbon fixation and soil, air and water contamination (Poffenbarger et al., 2017 - Figure 8).

Figure 6. Evolution of attainable yield, control crop treatment and replenish dose fertilization for corn crops in longterm tests (Source: Gudelj et al., 2017).

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Figure 7. Relation between relative aggregate stability at the test maximum, and replenish fertilization years in long-term tests (Draw up from Gudelj et al., 2017).

Figure 8. Conceptual relation between nitrogen fertilization and yield, corn residue production, and residual inorganic nitrogen (Adapted from Poffenbarger et al., 2017).

As regards to Scenario 3, studies conducted in Brazil and Africa showed examples of degraded soils, in which no responses to nutrients were observed (Tittonell & Giller, 2012). This scenario could be increasingly frequent in productive plots in Argentina's Pampa region. It is estimated that 30% of Argentinian territory–about 100 million hectares–is affected by water and air erosion (Casas & Damiano, 2019), resulting in a hardly reversible degradation. According to these studies, there is a damage registration growing rate of 200,000ha per year. In the search to satisfy growing demands, reducing yield breaches is a key objective. "Nutrient breach" would be responsible for a big part of yield breach. However, for the most part of cultivated soils in Pampa region,

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the reduction of the yield breach would be explained by the combined effect of nutrient availability and edaphic health enhancement. The analysis and adjustment to detailed scales and strong indicators are required when seeking for efficient and effective agriculture of low environmental impact, soil conditions variability, and nutrients and soil and crops management availability. Finally, it should be taken into account that nutrient needs can be covered with mineral fertilizers, organic composts, bio inputs and recycled products, and also from soil accurate management that allows crops to nourish within proper time, manner and quantity.

For the most part of cultivated soils in Pampa region, the reduction of the yield breach would be explained by the combined effect of nutrient availability and edaphic health enhancement.

REFERENCES

Check the references by entering: www.aapresid.org.ar/blog/revista-aapresid-n-217

CROP NUTRITION

Two sides of the same nutrient

When seeking for better yields, fertilization is an excellent ally. However, nitrogen fertilizer is a big cause of nitrous oxide emissions, a gas with high global warming potential. Some points for streamlining the use of this nutrient, and reducing economic and environmental costs.

By Alejandro Costantini¹ and Miguel Taboada²

¹ Director. Soil Institute. INTA. ² Head Professor. Edaphology. FAUBA.

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Argentine agriculture has been suffering significant changes, mainly within the last three decades. Some of these changes are related to a livestock farming relocation to areas with marginalconsidered soils for farming, together with the advance of the agricultural frontier toward weaker ecosystems, alongside no-till farming contribution (Viglizzo & Jobbagy, 2009). Up until 1990, grain production was developed with a very low usage of fertilizers (Álvarez et al., 2015), which was mostly attributed to a high level of fertility in Pampa region's soils. Over time, doses were increased in the search for higher and more stable yields (Álvarez et al., 2021). Currently, most used N sources in the main grain productive region are urea and UAN–Urea - Ammonium nitrate. Nitrogen fertilizers application can generate negative environmental impacts, especially when nutrient availability in soil is not considered or proper technology is not used. According to Davidson (2009), much of nitrous oxide emissions––N2O, a gas with high global warming potential––are because of nitrogen fertilization. The last National Greenhouse Gas Inventory showed that fertilizers participate in nearly 6% of said gas emissions. Although N2O emission is conditioned by factors that involve nitrification and denitrification processes, proper technology usage and accurate selection of type and dose of fertilizer, can lead to a more efficient usage of nutrients and, at the same time, can reduce economic and environmental costs.

Some Argentine experiences proved fertilizers' influence on N2O emissions. Álvarez et al. (2012) exhibited that during corn crop growing season, N2O emission peak was attributed to N fertilization made up with urea, as shown in Figure 1.

Figure 1. N2O emissions in no-till farming treatments with chemical fallow lands for sequences (×) sybn-crn–corn–, (▼) sybn-crn–soybean–, and (●) sybn-sybn–soybean–during cultivation period.

Other experiences directed at INTA's EEA Manfredi area, revealed that if the two most used fertilizers in the region are compared–urea and UAN–, N2O flows do not differ according to source (Figure 2), but they do regarding added N quantity–data not showed.

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Figure 2. Nitrous oxide emissions in corn (A) with urea fertilization treatments, and (B) with UAN in different N doses. Adapted from Álvarez et al. (2022).

It is worth emphasizing that accumulated emissions in corn crops within 90 days of several applied N doses, showed no differences independently of the fertilizer's source; therefore, N source was not a means to reduce emissions, at least among the compared ones. As regards application rates, there is evidence that emissions increase exponentially when nitrogen applications exceed crops demanded amount (Shcherbak et al., 2014). An alternative to manage this issue is the usage of other types of nitrogen fertilizers. In a 2011 study, Halvorson et al. describe the effect of a number of fertilizers of slow release, controlled release, and stabilized N sources as a means to reduce N2O emissions, and compare them with granular urea usage. All of the N "alternative" formulations had lower peaks of N2O emission than urea, and were also more efficient regarding the use of N.

The information presented can be a good prologue to establish the basis for debates about the need to reach a balance between environmental care, social well-being and economic development. It is not easy to accomplish said balance, mostly when considering that all natural resources used for production have an impact per se, that will be of higher or lower scale according to the capability and rationality of the performed productive activity. It is also true that this type of statement is, many times, at a risk of being declamatory–of undeniable veracity–, but of little value when taken into the field, where measurable parameters and clear definitions are needed, as Waseem & Kota indicate (2017). Fertilizer addition and type depend on some other factors that are sometimes ignored. Availability and price of N sources are essential determinants when choosing the N source to be used. However, in this choice, in which the economic factor plays a significant role, the usage efficiency of that N may not be properly addressed. Figure 3 shows possible destinies of added urea. It needs to be clarified that N minerals in soil can be absorbed by the plant or immobilized by microorganisms, but also it can be lost as nitrate by lixiviation or as N2O by denitrification, depending on environmental conditions. The loss of N as N2O has a strong impact on GHG emissions, while the loss in groundwaters, besides wasting applied fertilizer, may cause contamination problems in underground aquifers, including diseases to living beings. What is also clear is the problem of loss by erosion. On this basis, it is imperative the use of high-quality diagnose technology and fertilizers application and, although in this case urea is taken as an example, this advice can be applied to other N sources.

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Figure 3. Several destinies of urea applied on soil.

The risks of N losses can be reduced with the employment of numerous farming practices–such as cover crops that enable to use remaining N after harvesting, and generate biomass–that will contribute to soil cover and, eventually, improve OM content (Landriscini et al., 2019). Wang Li (2019) suggests the simultaneous investigation of nitrate lixiviation and losses by denitrification that leads to N2O production, since their starting point is N-NO3-. This expands the N cycle understanding and improves crop management, mainly by synchronizing NO3- availability and plants' demand.

Some final remarks

There are several matters that remain open in this brief article, but as final remarks, we are emphasizing some paramount themes. 1

Argentine agriculture needs to boost N use efficiency (NUE), primarily by enhancing farming practices in general and fertilization technology in particular. 2

The use of a certain type of fertilizer is often limited by availability and/or costs. Synthetic N fertilizer manufacturing is committed to sustainability due to its high energy cost, mostly in periods of energy crisis. 3

The usage of organic compost is promising from the perspective of both the closing cycles–circular economy–and the promotion of microbial diversity. Nevertheless, there are limitations regarding logistics, and also environmental risks similar to those existing with other fertilizers usage.

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When possible, it must be considered the major contributions to biological nitrogen fixation (BNF) of many species that provide large amounts of N. 6

It should not be ignored that each and every nitrogen fertilizer is responsible for N2O emissions into the atmosphere. Improved efficiency sources–inhibitors of nitrification, and urease and coated urea enzymes–are effective choices to mitigate these emissions, but not to suppress them. 7

In addition to all stated advantages and disadvantages, it is important to remember that N is paramount to "build" stable organic matter in soil. Carbon-based material contributions to soil organic matter increase have no use if there is not enough N to maintain the C-N relation characteristic of stabilized organic matter. This Carbon stored in soil will help not only with edaphic properties improvement, but it is also a means to mitigate GHG emissions produced within the sector by generated C capture.

ALTERNATIVE PRODUCTION

A toast between vines and vicia At the core of Cafayate city, "Ritmo Lunar" Biodynamic Cellar adds cover crops among its vineyards. Vicia is a strategic ally in this sustainable system par excellence.

By Agr. Eng. María Eugenia Magnelli To Prospective Program Aapresid

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Vicia is a remarkable cover crop (CC). Its ability to fixate atmospheric nitrogen and provide it to the system, its large biomass production, and its competence against weeds are some of its goodness. Moreover, vicia’s good behavior when facing drought, and resistance to cold weathers enable its adaptation into wide productive areas. We are used to referring to CC as a rotation component in extensive grain production practices. However, on this occasion, we are going to exhibit how vicia fits in a biodynamic organic vineyard, located in Cafayate city, in Salta province. Consequently, we talked to Diego Valsecchi, manager of Bodega "Ritmo Lunar", oenologist, wine producer and, above all, a restless person eager to employ ancient knowledge, characteristic of sustainability, planet's health and the species inhabiting it.

Biodynamic agriculture, sustainability to the highest extent One of Valsecchi's main objectives is to develop extremely high-quality wines without chemical compounds. As a first step toward achieving this goal, he needed raw material–grapes–that met said criteria. Taking action, he started an organic management of the vines. After investigations and experiences on foreign wine cellars–California, France, Italy–he ventured in biodynamic agriculture.

"Biodynamic Agriculture is based on the understanding of living soil, plants, animals and human beings. These four links work conjointly in a farming organism"

He tells us that this production concept was born 100 years ago in Europe, precisely in Germany, and in the last two decades had spread strongly around the world and in different crops. "Biodynamic Agriculture is based on the understanding of living soil, plants, animals and human beings. These four links work conjointly in a farming organism," he emphasized.

2000masl production The farm, as Diego likes to call the establishment– because talking about vineyards alludes to a sole crop and this is against the mentioned principles– has 25 hectares, 20 of which were destined to red and white grapes production, and the other 5ha are left as biological reserves. Some of the challenges when producing in Cafayate are low precipitation. In this desert area, it rains 180mm per year, occurring between late December, January and February. Consequently, irrigation is crucial, and that is why at the farm water is administered by a drip irrigation system. "At 2000 meters above sea level (masl), which is where we are now, there is low relative humidity, strong winds and high solar radiation. In this type of environment, it is very important to generate cover to reduce evaporation and monitor soil temperature," Valsecchi claimed. Taking the above into account, they plant pastures, cover crops, and harvest crops like wheat. For jobs in small spaces, they use tractors of 1.35m to 2.20m wide. They also had to custom-made a three-hopper direct seed drill.

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Vicia, a convincing option One of the aspects tackled by biodynamic is observation. Different actions or management strategies are suggested according to the features of each place or establishment. For the process of soil recovering, they sought annual species that fixate nitrogen and supply carbon, like alfalfa. It was then, when Vicia villosa emerged as an option. They started by combining it with oats to add into the system root volume that leaves grass. "Vicia grows well and finishes its cycle when vines bloom. Before applying the roller, a part of the land is used for seed harvesting, and the rest is left as seed bank for natural reseeding the following year," said the grower, and added: "We try to generate a living cover among vines, resulting in a high biological quality product–grapes and grain.”

Zero-cost fertilization and pest management In practice, the biodynamic method does not only imply to conduct a farm organically, but also includes preparation usage. It has already been mentioned the benefits of vicia as a natural fertilizer that adds nitrogen to the system. They also manufacture products through fermentation, and they use compost, which is made with all the cellar's residues, such

as native forest sawdust, farm's plant debris, certain minerals, and cows and chickens’ manure. "Compost provides a great mass of life to the soil," Vasecchi said. Similarly, chickens and sheep walk around the vines freely, as their stools contribute with more nutrients. Animals are a paramount piece of biodynamic systems due to their role of fertilizers.

"Health is a plant-nutrition balance, similar to homeopathic medicine," the grower mentioned. Nevertheless, for pest management they make their own preparations based on several plants and minerals in the area. He said that most of these products are preserved between 3 and 4 years, and can be employed in both small and large farms.

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A very important point in biodynamic agriculture is that every activity within the farm, in addition to the processes in the cellar, are conducted according to a calendar. To make the most of the effect that the moon, the sun and constellations have over the functioning of all living beings–as Greeks and Egyptians did–they create a schedule by choosing the moments that benefit farming activities. Thus, they have specific days for pruning, harvesting, making the preparations, etc.

A rainbow soil Bodega "Ritmo Lunar" follows Demeter standards, the most important international certifier that audits biodynamic farmers.

According to Diego, to prove how biodynamic the system is, they have to conduct a chromatography analysis of the soil. In their case, the result is a perfect rainbow, which verifies the land's good health conditions.

Farm-to-table Grapes produced in the farm are used for the manufacturing of red and white wine, which are stationed in oak or stainless-steel barrels depending on the case. "The field and the cellar work under the same philosophy, by seeking a much alive biological activity, for both fermentation as well as wine preservation," the oenologist stated. All of these considerations result in extremely high-quality and much more

interesting drinks. The totality of the production leaves the farm in a finished bottle. Currently, the cellar produces 60,000 bottles, with a potential of 180,000. As regards commercialization, they prioritize the domestic market, and sell their wine directly through a network of consumers that buy only organic products.

Sharing knowledge Another pillar of biodynamic agriculture is sharing the work that is conducted on the land. Valsecchi bountifully provides courses and experiential workshops in the farm. He also has a close relationship with the community and Universities in the region, so students can perform practices and experiences. Finally, Diego highlighted that biodynamic agriculture can be applied in any crop or production system, independently of the scale. He also advised that it is more complex, but when

we seek to surpass ourselves, this is the structure with more answers. In relation to our country, he emphasized that in this regard Argentina has great potential, with a strong demand on these kinds of products. Nowadays, markets are claiming a more friendly and healthier agriculture for the planet, both for the farmer and the consumer. It will be then necessary to take new paths in order to not be left out.

We thank Diego Valsecchi for his excellent disposition and valuable contributions, and Gisela M. Magnelli for making this note possible.

ALTERNATIVE PRODUCTION CIENCIA Y AGRO

Bombilla Guaraní, a toucan-related enigma revealed by Jesuits, and the 'gracias' traveling from Argentina to the Middle East:

the amazing story of Yerba Mate Mate is a symbol for identity that connects all Argentinian people. From its origins to the present time, yerba mate has been a vital part in our country's culture and daily life. We invite you to immerse yourselves in the history of this traditional infusion that is gaining popularity both at a national and international extent.

Is there a bigger symbol of identity to us Argentinians that goes hand in hand with our flag, asado, dulce de leche and soccer? Of course there is: mate! A registered trademark distinguishing us worldwide.

By: Agr. Eng. Antonella Fiore Prospective Program - Aapresid

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As the Argentine writer Hernán Casciari described in one of his stories, we realize that an Argentinian individual becomes an adult by drinking their first mate alone for the first time, without anyone by their side.

Mate accompanies us day by day throughout our entire lives. When we welcome guests into our homes, we suggest drinking mates, and we do the same when we want to approach somebody to chitchat. Mate not only accompanies, but also unites people. In Argentina, mate is the most consumed beverage after water, making no distinction between gender, age or social class. According to the National Institute of Yerba Mate (INYM in Spanish), Argentina consumes an average of 100 liters of mate per person every year. The tradition of mate is present in more than 90% of Argentinian homes.

To prepare this renowned infusion, apart from the bombilla–a metal straw–, the thermos, water at less than 80°C and the mate itself–container–, it is necessary a key ingredient: the yerba mate, whose scientific name is Ilex paraguariensis. How did yerba mate emerge? Is it consumed in other countries? In Argentina, where is this crop cultivated? What are its environmental conditions? Are we the country with the major consumption of yerba mate in the world? What about the major producer? This article will try to respond to these and further questions.

From Guaraníes times to present days As stated by Pau Navajas in her book "Caá Porã: El Espíritu de la Yerba Mate", the discovery of yerba mate can be attributed to Kaingang ethnicity 3000 years B.C. This ethnic group consumed Ilex paraguariensis or yerba mate tree, native to the Paranaense forest in Argentina, Brazil and Paraguay. However, it was Guaraní people–aboriginals from several South American countries–the ones who exploited the benefits of yerba mate as well as refined harvest and preparation methods, along with drinking manners, by placing the leaves inside a pumpkin filled with water and drinking it through a straw made out of cane. To Guaraníes, yerba mate turned into an exchange currency with other pre-Columbian people: Incas, Charrúas, Araucanos and Pampas, who, as a result, embraced mate in their own cultures. When the Spanish arrived in South America, they learned from the Guaraníes the usage and benefits of mate, quickly gaining great popularity and, therefore, yerba mate was carried from its origin lands to the entire territory under Spanish domain. Jesuits were the ones responsible for spreading mate consumption in a remarkable way. They realized the huge economic potential it would have if it were to be commercialized, so they proposed to research why yerba mate plants germinated only in that region of the world. Thus, they discovered that the secret for sowing was predigested seeds by toucans. Toucans fed from

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yerba mate's berries and the digestive process cleaned the berry. This discovery was validated half a century later by the French naturalist Aimé Bonpland. Motivated by this process, Jesuits were pioneers in cultivating, transporting and commercializing mate, although they rather drink it in small tealike bags, not with straws as Guaraníes did. From there, at some point, yerba mate became known as "the tea of Jesuits". Despite yerba mate industry originates among Guaraní people–native from Paranaerense forest, where yerba mate grows naturally–its consumption spread throughout South America during the Spanish Empire, leading the yerba mate industry to reached a peak in every region in Río de la Plata. In the late XVI century, the Spanish were already thoroughly consuming yerba mate and boosting the industry in Paraguay. This country became the main center of production, until territorial disputes favored the expansion of mate toward many colonial cities in South America. With the defeat of Paraguay at the Triple Alliance war, the Paraguayan region of Mato Grosso do Sul became part of Brazil, and by the end of the XIX century yerba mate plantations began to be cultivated, turning Brazil into a primary producer. In the early 20th century, the first industrial plantations were established in Argentina at ports in the South, Rosario city and Buenos Aires.

Nevertheless, Argentina had to import yerba mate from Brazil and Paraguay through the Paraná River in order to fulfill domestic consumption, until the French-Argentine landscapist, Carlos Thays, successfully developed a system for seeds germination. Thus, arises the Argentinian yerba mate industry. Nowadays, our country is the main producer and exporter of yerba with 54% of the global market. Within this framework, mate is increasingly gaining popularity beyond Latin American limits.

Carlos Thays discovered the seeding formula. With seeds obtained from Paraguay, he studied several procedures, until he managed to germinate them by subjecting the seeds to an extended immersion in hot water before sowing them (source INYM).

Understanding the species: preparation, management and favorable conditions. Ilex paraguariensis is a shrub characterized for reaching 10-30m height in its natural state, although for harvesting it is kept below 2m. It has evergreen, thick and dark green leaves. Yerba mate plant grows little whitish flowers and the fruit are small red pellets. Ilex paraguariensis is mainly cultivated in the subtropical humid Argentine region–in Misiones

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and Corrientes provinces–where precipitations reach around 1800mm annually and average temperatures are about 21°C. Said plant also needs red soils, typical in these regions, which provide the required acidic levels and minerals. The soil is particularly important for the plant to grow, and pH values cannot exceed 5.8 or 6.8.

For some time now, several yerba companies have employed cover crops in plots, aiming at not only increasing productivity but also taking care of the soil. Cover crops, such as ryegrass– grass with a high developing volume of superficial roots; or wild turnip–with a more taproot system– collaborate properly on yerba plantation systems as they increase soil's porosity for water access.

In this INYM video, you can see the case of Jorge Lizzinienz, who with patience and through the usage of cover crops, such as ryegrass and wild turnip, is recovering soil's fertility and yerba's productivity.

Even though the plant has a robust appearance, it is extremely sensitive and cannot endure direct sunlight. Consequently, it is ideal that they grow in dim-lighted spaces. In South America, light conditions are even due to surrounding high trees. Moreover, caffeine content also depends on the amount of sunlight. The more exposed to sunlight the yerba mate plant is, the more stimulating it will be. Most yerba mate plants grow between 400 and 800 meters above sea level. The taste of mate depends on each area’s climate conditions. That is why, according to the region it is grown, it can be bitter or smoother. From 8kg of the yerba mate fruit, we can obtain 1kg of seeds, meaning around 135,000 seeds. From this amount, between 20 and 30 thousand germinate. These dry seeds are sowed amid March and April. When the first leaves sprout, the plants are taken to a nursery from 1 to 2 years before being transplanted into the field, where they would remain the following 3 to 5 years before the first harvest. Regarding transplantation density, there are:

Low density: 1,600 plants per hectare. Medium density: 2,200 plants per hectare. High density: more than 2,200 plants per hectare.

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Yerba mate plants can have a productive life of up to 100 years. Pruning is done as of the second or third year since plot transplantation–subject to plant development state–up to the fifth year from the first harvest. Pruning period ranges from mid-July to early September. Production increases within 5 to 10 years and then it stabilizes. When productivity begins to decrease and plant structure gets damaged, renewal pruning must be performed. Nearly 15 years after production starts–according to management methods–between May and July it is wise to carry out a crown reduction. Yerba mate infusion is obtained from the Ilex paraguariensis plant's dry grinded leaves and branches. Leaves harvesting is usually done manually, although some yerba mate companies have special machines. It starts in December throughout next September, being April-August the most appropriate period, while October and November are prohibited. When the harvest is finished, the yerba mate tree regenerates and produces more leaves. After the harvest, it is time for the phases known as zapecado y drying. Leaves are exposed directly to the heat of the fire to delay fermentation and oxidation processes. Later, they are exposed at temperatures of 100°C reducing moisture down to 3-5%. Once dried, leaves are grinded, and the result is what we call toasted yerba mate.

Afterward the canchado process occurs–a first thick grinding of yerba branches and leaves that overcome the drying phase. The purpose of this process is to reduce the volume of the product for the subsequent packing and storing. It must be initiated within 24 hours after the harvest in order to avoid fermentation and damage of the product.

3kg of green leaves= 1kg of Yerba Mate canchada

The time the product is stationary determines the flavor, the color and the scent characterizing the numerous varieties of yerba mate. These features are the result of a maturing process closely monitored by professionals. The time the product is stationary ranges from 10 months to 2 years according to the company. There are also accelerated stationary systems on environmental chambers which can reduce this period up to 60 days.

This process ends with milling, where yerba is treated based on its variety, the way it was harvested, and the time of year in which it was processed. All different parts of the plant are mixed in a variety of proportions, subject to the plant's origin and the brand producing yerba mate. In relation to yields, the National Agricultural Technology Institute (INTA in Spanish) in Cerro Azul, accomplished a genetic improvement program and increased average yields from 3 to 7.4kg per plant in the last 50 years.

Yerba mate varieties Yerba mate contains three main elements that determine its flavor:

Leaves the prime element of yerba mate, as they have much of the flavor, which is spread through the whole process.

Powder

sets the intensity of the flavor at the beginning of the infusion’s preparation. Powder infuses and diffuses faster than leaves, losing its flavor rapidly.

Branches the stems of yerba. It is the element with less flavor; it allows the "diluting" of mate making it less strong.

For the traditional mate, there are 3 leading types of yerba: With branches: the most traditional yerba. Consists of all 3 elements of yerba mate–leaves, powder and branches–and it could be said that it is the most balanced.

Without branches: it is a stronger yerba. Consists only of leaves and mate particles, that is why the taste is naturally stronger and bitter.

Low powder content: contains minor amounts of powder, therefore, it is a less strong yerba and it is more homogeneous throughout the tasting.

IMÁGENES: GENTILEZA INYM (INSTITUTO NACIONAL DE LA YERBA MATE)

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Consumption and exportation According to an INYM report based on both selfdeveloped data and the Argentine Ministry of Economy, in 2020 the consumption of yerba mate per person was 5.92kg, with a population of 45,376,763 people, and a domestic market delivery of 268,826,525kg of manufactured yerba. Whereas in 2005, consumption was 6.32kg per person, in a country with 38,402,889 Argentinian people and sales of 239,907.422kg of the manufactured product.

Germany, Spain, France, Poland, United States, Chile, Mexico and Canada, and since 2021, this Argentinian food has reached the Indian market. So far this year, exports nearly attained 30 million kilograms, and if this current pace is maintained, a close 40 million kilograms are expected for the end of the year.

Data shows that in the last 15 years, both population and number of kilograms increased, although consumption per person decreased. Mate is an Argentinian export custom, and there are more than 50 countries buying our yerba today. Argentina is the major producer and exporter of yerba mate globally. The ten most important markets are Syria, Lebanon,

Argentina is the major producer and exporter of yerba mate globally.

Argentinian Yerba Mate: growing reputation in Syria and Lebanon Syria and Lebanon are the primary importers of Argentinian yerba mate. Even though it is somewhat surprising, the consumption of yerba mate in these countries is a long-time habit. How did yerba enter the Middle East? As a result of migration flows. It is estimated that around 800 Syria and Lebanon citizens started to settle in Argentina between 1860 and 1870. A census carried out 75 years later, in 1947, indicated that 32,789 Syrian and 13,505 Lebanese people lived in our country.

"Currently, Arabic descendants are considered as the third migrant-background-group in Argentina after Italians and Spaniards," revealed a report published in 2011 by the National Scientific and Technical Research Council (CONICET in Spanish); however, knowing the exact up-to-date number is difficult to obtain. The returning of some of those Syrian and Lebanese people back to their countries after having embarked was what connected Argentina with Syria and Lebanon.

Syrians usually drink mate individually, in little glass cups and with a metal straw–bombilla; each one with their own mate but all sharing one kettle, which is placed on the table or on the floor above a special portable gas tank to maintain the temperature. For those few cases where mate is shared, there is a word that the invitee says to indicate to the cebador–the one offering mate–that he does not want mate anymore: gracias–thank you in Spanish. The same word Argentinians say. They do not use the word shrúkran (thank you in Arabic), but gracias in Spanish. An unchanging expression, a code among those offering and those who are offered mate, and that traveled from Argentina to Syria and Lebanon.

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A round of mates and data November 30 is considered as the national mate day. This date was chosen to commemorate the birth date of Andrés Guacurarí y Artigas (AKA "Andresito") in 1778. He encouraged production, and promoted yerba mate commercialization during his term as governor of Misiones Province between 1815 and 1819. He had indigenous roots and José Gervasio de Artigas as his contributor, who acted as his godfather and adopted him legally.

For those who like to travel, you can learn more about this crop by following what is known as “La ruta de la yerba mate”. It is the main food route of the Mercosur and the brand representing the Argentine yerba. It crosses the entire territories of Misiones and the North of Corrientes provinces, and it is organized in circuits.

Every year in November, and celebrating its 45° anniversary, the "national and international festival of yerba mate" is conducted in Apóstoles city, Misiones.

Yerba mate has beneficial properties for the human body. It provides large amounts of polyphenols, B complex vitamins, potassium, magnesium and xanthines. Polyphenols work as powerful antioxidants and help to increase the body's defenses and diminish cellular aging. Moreover, complex B vitamins help the body to better absorb food energy. In addition, potassium and magnesium are key for the proper functioning of the heart, and xanthines stimulate the nervous system, helping us to be more active and focused.

The path of Yerba Mate It can reach 10-30m high in natural state

The crop

10/30m

Yerba mate tree Ilex paraguariensis

It is kept below 2m high for harvesting

1 2

Dry seeds are sowed between March and April.

Later they are transplanted into the field, where they will remain the following 3 to 5 years before the first harvest.

Harvest

It is done between 3 to 5 years after sowing.

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When the first leaves sprout, the plants are taken to a nursery from 1 to 2 years.

It is done manually, starting from January to May until September

Sapecado y drying

Canchado

Leaves are exposed to the fire at temperatures of 100°C

The first thick grinding of dry leaves is carried out in order to facilitate packing

Statinary time

It determines the flavor, the color and the scent The maturing process is closely monitored by professionals. It varies between 10 months and 2 years

Milling and packing

After stationary time, yerba mate already canchada is grinded finer. Grinding is performed considering the type of yerba and its origin.

Afterward it is hermetically sealed and the INYM stamp is placed.

ALTERNATIVE PRODUCTION

Coffee with sustainable aroma: Argentina joins Latin America’s organic production revolution Yes, you read correctly, Argentina joins Latin America’s organic coffee revolution. We will convey to you how the production and consumption methods of this millennial infusion are changing. From its origins to innovations with residues. An opportunity to promote and encourage more sustainable coffee-based practices.

By Agr. Eng. Antonella Fiore Prospective Program - Aapresid

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For many years, there has been a paramount controversy about the customary production of coffee. It is that the cultivating methods employed by our ancestors–exposing crops to the sun– resulted in major water loss and soil deterioration. Is there in the world a more sustainable manner to produce coffee? The answer is positive. Through a productive approach, usually known as "organic", it is possible to protect the edaphic

profile, its microflora, reduce carbon footprint and avoid the excessive loss of water when cultivating coffee. In Latin America, coffee producer countries such as Honduras, Venezuela, Peru, Colombia and Brazil are conducting this environmentally friendly initiative, which started several years ago.

Generally, we think of Argentina as a pioneer in extensive farming productions such as soybean, wheat and corn, and we accept the fact that we do not have the possibility to accomplish this type of "alternative production" commonly performed in tropical climate countries. However, is it actually true? What if I tell you that Argentina has the capability to produce coffee? It could probably be a surprise to know that in the Yungas of Salta province coffee plantations are already implanted and working, producing Argentine coffee beans being commercialized indeed. There is so much yet to discover. That is why we invite you to learn further details about the main character of this article: coffee.

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Coffee origins: from Africa to the world. Coffee history begins in Ethiopia, Africa, where it is believed it emerged in the province of Kaffa. Slaves transported from what is known today as Sudan to Yemen and Arabia through Mocha port used to eat the flesh of coffee cherries. It is known that in the XV century coffee was already cultivated in Yemen, but Arabs had a strict policy of not to export fertile coffee beans so as to avoid cultivation elsewhere. Coffee bean is the seed of the coffee tree, but when the outer layers are removed it becomes infertile. There were several attempts to seize coffee trees or coffee beans, but eventually the Dutch won the race in 1616 when they managed to take some to the Netherlands and cultivated them in greenhouses. As regards commercialization in Europe, traders from Venice were the first ones to sell coffee in 1615. This occurred simultaneously with the arrival of the hot chocolate from America to Spain in 1528 and the introduction of the tea in Europe in 1610. The first European coffee shop was Caffè Florian of Saint Mark's Square in Venice, which opened its doors in 1720 and it is, to this day, open to the public.

But when did coffee arrive in the Americas? The first reference as to coffee consumption in North America dates from 1668, and soon after coffee establishments were set up in cities like New York, Philadelphia, Boston and some others. Nevertheless, coffee cultivation in America did not start until 1720.

French Guiana and the first of many in Brazil. In 1730, the British took coffee to Jamaica, being Blue Mountains where today the most famous and expensive coffee in the world is cultivated. In 1825, Hawaii planted coffee for the first time, which is the only American coffee and one of the best globally.

The Dutch continued to be the main characters in this story by being the first ones in introducing coffee into the continent by distributing coffee trees in Central and South America, which nowadays reigns as the major crop with commercial purposes within the continent. In 1718, coffee reached the Dutch colony in Suriname. Later, coffee plantations were set in

Currently, 85% of the coffee in the world is produced in Latin America. The rest is divided between Asia and Africa with 10% and 5% respectively. Brazil is the main producer with 2.2 million tons cultivated in a 2.3 million hectares area. Following Vietnam, Indonesia and Colombia producing between 0.6 and 1 million tons in a combined surface of 2.6 million hectares.

The revolution of "shade-grown coffee" in Latin America. The most widely cultivated coffee variety in Latin America is Arabica coffee–Coffea arabica–and its by-products. Coffea arabica is a big bush with oval and dark green leaves. Its fruit is also ovalshaped and matures in a period of 7 to 9 months. Coffea arabica is considered the best bean due to its balance, scent, less viscosity and less acidity, which makes it more palatable. As an additional fact, it contains less caffeine than other varieties.

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According to Manual de producción sostenible del café from the Inter-American Institute for Cooperation on Agriculture (IICA in Spanish), ideal environmental conditions for coffee cultivation are:

Altitude: coffee can adapt to altitudes ranging from 500 to 1400masl, although to obtain good quality coffee it is suggested an altitude over 700masl.

Temperature: coffee cultivation optimal range is between 18°C and 22°C. Temperatures under 18°C promote vegetation growth and reduce coffee flower differentiation rate, whereas temperatures over 22°C hasten vegetation growth and affect flowers and fruits. Thermal amplitude above 10°C fosters blooming.

Precipitations: ideal annual precipitation quantity varies among 1600 and 1800mm, with a proper distribution. Short periods of drought are considered beneficial for blooming. Contrarily, abundant rainfall hinders it. Water shortage favors blooming but restricts both growth and development of the fruit.

Wind: this climatic component is of major importance because it increases plants evaporation and transpiration as it gains speed. Strong airstreams can dry and break leaves, fresh sprouts and flower buds, that is why wind is reduced with shelterbelts in coffee plantations.

ensure additional benefits such as firewood, fruits, timber and stubble to work subsequently as soil cover. Generally, the trees used are from the Legume family due to their ability to biologically fixate atmospheric nitrogen, which improves the soil’s natural fertility. However, it is important that these trees do not compete for nutrients against coffee trees. They must provide enough protection against sun's rays, and behave as climate and environmental factors regulators along with soil and air temperatures, to ensure an optimum development of coffee plants. Species used for permanent shadowing of coffee plants: Inga edulis (known as ice-cream bean or guama).

Relative humidity: must be lower than 85%, since high levels of humidity benefits fungal diseases development. Microclimates produced by shadows, the plant’s development, and proper weeds management influence relative humidity adjustment. To start organic coffee plantations, selecting good quality coffee beans is key. These beans are cultivated in greenhouses for 5 months to develop seedlings. Later, these seedlings are transplanted into fields under silvopastoral systems. The trees used to provide permanent shadow need deep root systems–beneath coffee tree roots–, evergreen leaves so the plant has foliage throughout every season of the year, and not be host to any pest or disease. Moreover, they must have great regenerative capacity and

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Albizia carbonaria (known as carbonero or naked albizia). Erythrina fusca (conocido como pízamo, búcaro o cámbulo). Erythrina fusca (known as coral bean tree, bucayo or Chekring). Cordia alliodora (known as laurel o capá prieto). It can take a period of 2 to 4 years between the sowing and harvesting of coffee cherries–which is the name of the fruit. Fruit ripening can take between 6 and 11 months, according to variety,

temperature and humidity. Once coffee cherries are ripened, it is time for harvesting. Shade-grown coffee plantations are harvested manually, where only cherries in their peak of ripeness are selected, guaranteeing a major quality harvesting. The selected cherries are red or yellow-colored depending on the variety. To keep coffee trees around 2m high, it is necessary for the plant to be pruned regularly. This facilitates the caring and harvesting of coffee.

Image Credit: www.mundocafeto.com

Argentine all the way: coffee produced in the Yungas of Salta province. Against all odds, Argentina also owns coffee plantations. In the north of Salta province there is a coffee plantation revived by the grower Graciela Ortíz aiming at retaining her father and uncles' work. “Café Baritú” farm is located in Aguas Blancas city, in the Yungas region in Salta, a landscape of great environmental diversity, with connected forests in a smooth continuation of the Amazon Rainforest. In this particular setting, Graciela–the only coffee grower in the country– alongside her family, produces 100% Saltaorigin and thoroughly organic coffee.

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Graciela's father, together with his brothers, decided to dive into coffee plantations after participating in the state program "Salta café", starting the activity in the 70's. "At first, technicians and engineers came from Brazil and mentioned that the northwest strip of Salta province has favorable climate conditions for sowing coffee," Ortiz said. In the 90's, with the famous one-to-one exchange rate of the presidency at the time, the Ortiz family and other coffee growers had to abandon their plantations. It was not until 2009 when Graciela decided to take back the land. All those years of abandonment forced her to start from scratch, having to focus on preparing the land, growing new plants and restarting the cultivation process once more. This allowed the Ortiz family to plant 30 hectares of land in the farm. Graciela says that from each plant you can obtain 1kg of coffee, and according to the place in the world where it is sowed every coffee bean "acquires the flavors from where it grows". In the case of Café Baritú the most characteristic feature is its chocolate-ish flavor. Graciela explains that it is a 100% natural crop that takes a 4-year process until it produces suitable beans for the first harvest. Blossoming begins in December; harvesting is done between July and August and then the beans are moved for drying. At this last stage, Café Baritú coffee goes through two types of drying, natural and washed. In natural drying, once the bean is harvested, it is placed directly on raised beds. This process provides coffee with a sweeter flavor. However, washed drying is more complex and entails a fermentation process which includes

the removal of the fruit flesh and washing, for the later transfer to raised beds. Ortiz has a coffee shop in Jujuy province and in the following months will open another one in Salta province "to finish closing the cycle". "We manage the entire coffee cycle, from producing it, all throughout harvesting and drying, to the selling in our shop. As the daughter of a grower, I set myself the goal to make our own coffee and sell it in our own shop," she said. She claims that the key is "to be patient" and "to fall in love with one's work". "If one is objective, develop a plan and execute it, all is possible," the coffee grower affirms. Upon the closure, she said that in Northwest Salta there are favorable conditions to produce tropical crops such as papaya, mango, banana and others besides coffee. Actually, there are some producers already encouraged to start growing them, the only thing missing is a few conditions that guarantee them medium or longterm benefits for undertaking said production.

Nothing is lost, everything is transformed (or reusable) According to the documentary about coffee "¡Viva el café! Variedades selectas y ecológicas”, Nicaragua is boosting notable changes on coffee plantations. As SVP Marketing & Sales of The Coffee Cherry Co. in the United States, Carole Widmayer is carrying out tests to find a usage alternative of coffee flesh, a "highly nutritious food being neglected," Widmayer claims. In Nicaragua, there is a company manufacturing by-products from this so-called "residue".

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Thus, they are creating a new market based on this derivative or "new raw material". The flesh and skin, leaving aside the bean, represent 40% of the coffee dry weight, although surprisingly 322 million tons of flesh are thrown away every year. The company for which Widmayer works uses the dry flesh to produce flour and flakes. Contrary to popular belief, the flesh, which can be red or yellow, is edible and contains caffeine, antioxidants, minerals, proteins and fibers.

In the United States, some restaurants and bakeries have already included coffee flesh in their dishes. In Seattle, chef Jason Wilson, whose restaurant The Lakehouse works conjointly with The Coffee Cherry Co., is developing new recipes such as cakes and muffins based on this ingredient.

Image: https://coffeecherryco.com/

The main objective is to produce 100% bio-based and biodegradable materials from gastronomic residues, like coffee grounds, to promote waste circularity and reduction.

Argentina is not lagging behind in this trend. As reported in the website of the Argentine national government–www.argentina.gob.ar–, a local and national company is dedicated to creating 100% degradable materials from organic residues, including a cup made out of coffee grounds. As mentioned in the article, Étimo Biomateriales emerged in 2021 as a university project by its director Camila Castro. The main objective is to produce 100% bio-based and biodegradable materials from gastronomic residues, like coffee grounds, to promote waste circularity and reduction. Currently, the company is in the process of developing its first product, cups made out of coffee, fabricated from coffee waste. They use waste from different coffee shops and combine it with binders to create the material which they later shape in their workshop, located at the Metropolitan Design Center (CMD in Spanish).

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Image: www.instagram.com/etimo.biomateriales

These examples prove that the organic coffee production revolution not only is here to stay, but it is also leading to the discovery of other options regarding the thorough production of traditional and centennial crops. When it comes to food production it is important to keep an eversustainable view and to look after one of the most vital resources: the soil.

REFERENCES

Check the references by entering: www.aapresid.org.ar/blog/revista-aapresid-n-222

Organic coffee in Latin America

What is organic coffee? It is a method of coffee production focused on the cultivation of coffee in a sustainable and environmentally friendly way. Permanent shadow is an organic coffee crop shared feature that benefits biodiversity.

Benefits Protects the edaphic profile and the soil's microflora. Reduces carbon footprint Prevents excessive water loss.

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Latin America producer countries Colombia Brazil Honduras Venezuela Peru Argentina

Credits: The coffee Cherry Company

Reused residues Coffee flesh and other organic residues are recycled to manufacture products such as flour and flakes, reducing waste and promoting circularity. In Argentina, Étimo Biomateriales company works in the development of a cup made out of coffee, fabricated from coffee waste.

LIVESTOCK FARMING

Planning for data to play at home Argentine livestock farming is facing the challenge of reducing greenhouse gas (GHG) emissions, especially N2O. Precise data generation and sustainable strategies employment, such as promoting legumes in pastures, seek to mitigate environmental impact and enhance livestock farming sustainable production.

Within the context of climate change being an undeniable reality, livestock farming activity has become one of the foremost debates, since its negative environmental impact is GHG emissions, which simultaneously contributes notably to the global warming process. By Gabriela Pérez¹ and Alejandro Constantini²

¹ Professor and doctoral student. Faculty of agronomy, University of Buenos Aires (UBA in Spanish). ² Soil Institute Director at National Agricultural Technology Institute (INTA in Spanish). Faculty of agronomy professor at UBA.

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Thus, as a country with a strong livestock farming tradition, and one of the main quality meat producers worldwide, Argentina is at the core of the debate. According to Godfray et al. (2018), the world's population and animal protein consumption are continuously increasing, leading to a forecast growth in the meat market. This growth should be sustainable and minimize environmental costs.

In 2009, Steinfeld et al., estimated that the livestock farming sector emits nearly 7.1GT of CO2-eq year-1 globally, meaning around 18% of total anthropogenic GHG emissions. As stated in the fourth two-year period update report of the national GHG inventory published in 2021, in Argentina, livestock farming is responsible for 22% of total GHG emissions. That is why it is crucial to generate precise and domestic data. This will allow significant calculation accuracy in Carbon usage per unit of product, so as to provide answers to several negotiations involving potential "environmental para-tariffs barriers" that could undermine the country's farming product exports, bovine meat among them.

As a country with a strong livestock farming tradition, and one of the main quality meat producers worldwide, Argentina is at the core of the debate.

In quantitative terms, the primary GHG emitted by livestock farming is methane CH4. However, one of the greatly interfering processes in GHG global emission is N2O edaphic emission, generated by excretion depositions in the soil. Globally, between 1990 and 2017, N2O emissions originated within the farming sector represented an average of 72% of total N2O emissions, according to estimates published by FAO in 2020. In Argentina, the farming sector generates 95.2% of N2O emissions, from which 31.1% is issued from animal excretes in pastoral systems. Nevertheless, Gerber et al., proved in 2013 that simple strategies, such as grazing management improvement and legumes integration in pastures, could retain 287 tons of CO2-eq of C per year globally, over a 20-year period.

In 2017, official figures reported that Buenos Aires province supplied 35% of the country's head of cattle. 48% of the province's livestock inventory is in Cuenca del Salado region. Generally, its soils have high soluble salt concentrations that can vary depending on the profile's moisture content and water table depth (Vazquez, 2011). Therefore, a great area of the region is not suitable for agricultural production. One historically predominant livestock system in the region is the extensive type, with considerable variations in fodder supply throughout the year (Otondo et al., 2014). To improve pasture receptiveness and quality, a Lotus tenius promotion practice is conducted in the area. This legume naturalized in the region has a high ability for natural reseeding and soil adaptation with halo-hydromorphic problems (Marinoni et al., 2017). The promotion practice consists in favoring this species growth in late winter to improve its competence capabilities, mainly concerning a few grasses. Although some authors claimed that major legumes presence in pastures could assist to N2O emissions by a greater N availability, it

The greater presence of legumes in grasslands could improve the physical conditions of the soil and increase carbon storage by providing material with a low C/N ratio.

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could also enhance soils' physical conditions, and boost C storage by providing low C-N relation material (Sisti et al., 2004). Consequently, the livestock farming sector contributes to a large part of anthropogenic GHG emissions; however, it could cooperate significantly with necessary mitigation efforts. From the equation composed of potential N2O emissions–contributing to Carbon capture by adding N into soils, enabling to stabilize organic matter and methane emissions–will result in the actual system's capability to increase or mitigate GHG emissions. In this sense, it is important to emphasize that tannin content in legumes is a critical factor when analyzing emissions.

In Argentina, within the livestock farming sector, there is an ongoing research work that consists in quantifying and analyzing N2O emissions and C storage produced in pasture soils in Cuenca del Salado, committed to direct livestock grazing with and without Lotus tenuis promotion. To that end, it was conducted a collection of stool and urine samples and high frequency nitrous oxide in soils–control treatment. These samplings were never less than six weeks and were carried out throughout an entire year, focusing on the most characteristic moments of each of the four seasons.

High frequency samplings conducted seasonally, even in winter–when many of the bibliography dismiss GHG emissions due to the region's low temperatures–, enabled the observation that N2O emission values, although low, were measurable and under no circumstances insignificant (Figure 1).

Figure 1. N2O emission evolution originated from manure in a livestock farming system with intensive grazing. Bars represent the average standard error between manure treatments.

When integrating collected data, the results suggested that, in this region, N2O emissions with added bovine manure increase edaphic N2O emissions by 5% in relation to control. This situation can be compared with the one between a farm with and without grazing animals, which was made considering animal stock, and amounts of urine and manure left in the paddock during the studied period. Similar calculations are being carried out for the other seasons of the year (Figure 2).

Another interesting result of this study, showed that there is no effect of legume integration over N2O emission during summer season.

Figure 2. N-N2O accumulated emission during the experiment's winter days period for control treatments–only soil emissions measurement without manure–and with added bovine manure.

Another interesting result of this study–not yet published–showed that there is no effect of legume integration over N2O emission during summer season, which would imply that it is possible to increase dietary quality without notably increasing N2O emissions in the system (Figure 3).

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Figure 3. Accumulated emissions by static chambers during summer for control treatments–soil without manure–, manure and urine in systems with integrated legumes–"Lotus"–, and no integration–"pastures"–the error bars represent average standard error.

This type of studies, expensive from the point of view of investigation time, equipment and analytical determination, is highly important for the acquisition of local emission factors that allow us to face our own data in our own conditions, with default factors provided by the IPCC. This would enable us to know where we are standing regarding eqC produced per unit of product, and thus knowing if we are capable of improving our production efficiency by making it more sustainable from an economic, productive and environmental perspective.

This article has been drawn up partially with the financial support of FONTAGRO, the Ministry for Primary Industries of New Zealand and PROCISUR. Opinions expressed here are solely responsibility of the authors.

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