14 minute read
BADGER BEAT
Rethinking Diagnostic Detection Methods for PVY and Other Potato Viruses
By Brooke Babler, Dr. Kutay Ozturk, John Hammel and Dr. Amanda Gevens
RUSSETS
• AO8433-4STO • Caribou • Lakeview Russet • Plover Russet • Reveille • Silverton • Umatilla • Vanguard
YELLOW FLESHED
• Yukon Gold
WHITES
• Lady Liberty (NY152)
REDS
• Dark Red Norland
Contact us now
to place your Spring orders or for more details!
“Wolf River” Brand Specializing in Certified Seed
Foundation & Certified Seed and Promising Experimental Varieties
Bula Potato Farms, Inc. • W11957 Highland Road • Antigo, WI 54409
Call Dennis or Adam: Work: (715) 275-3430 • FAX: (715) 275-5051 • www.certifiedseedpotatoes.com Email: bulaseed@frontiernet.net or dennis@certifiedseedpotatoes.com
Since 1913, the goal of the Wisconsin Seed Potato Certification Program (WSPCP) has been to provide seed potato planting stock that is healthy and without varietal mixture. This goal continues to be the incentive of the program as we advance forward.
Although there have been some recent changes within the program, staff continues to focus on ensuring seed potatoes in Wisconsin are of the highest quality. In addition, research continues to be a driving force in Wisconsin to maintain a thriving seed industry. In this article, we explore interesting research topics that advance and innovate certification testing of the future.
WHAT IS PVY?
Potato virus Y (PVY) is an economically important pathogen of solanaceous crops worldwide, and currently the most important viral
Above: Wisconsin Seed Potato Certification Program staff and college graduate students observe the PVY plots at the University of Wisconsin Extension Langlade County Airport Potato Research Station, in Antigo, during summer 2022.
pathogen of potato as the primary cause of seed lot rejections in most certification programs. The virus is transmitted horizontally between plants through mechanical transmission or aphid vectors and vertically across generations through infected tubers. PVY is a monopartite virus (~9.7kb) belonging to the Potyvirdae family of viruses, the largest family of RNA plant viruses containing some 160 single-stranded, positive-sense RNA species. Originating in the Andes of South America, PVY was disseminated worldwide through global trade. The virus was first identified in 1931 as one of the those correlated with a disorder then known as potato degeneration and has since evolved into various distinct viral strains. While genetic resistance to PVY exists, most commercial potato varieties remain susceptible, and thus, avoiding on-farm introduction through infected tubers is essential for effective management. The potato industry relies on the production of disease-free seed stocks through risk mitigation and certification.
VISUALLY DETECTING PVY
The Specialty Crop Research Initiative (SCRI) project “Development of Sustainable System-based Management Strategies for Two Vector-borne Tuber Necrotic Viruses in Potato” brings together researchers (including leadership from the University of Idaho and participation from the University of Wisconsin [UW]-Madison), Extension professionals and seed certification programs from across the country. Their purpose is to address the most important disease problem currently faced by the potato industry—vectorborne tuber necrotic viruses. Potato Mop Top Virus and some strains of PVY elicit necrotic response in tubers, reducing crop value or rendering it unmarketable. For the past decade, the program has been working under the guidance of a national advisory board comprised of leading seed growers, affected potato growers and representatives of large potato processing companies to prioritize our research activities. One aspect of the project provides a demonstration of PVY strain type symptoms on selected potato varieties. This demonstration was conducted at the UW Extension Langlade County Research Station, in Antigo, during 2022.
INOCULATED MARKET CLASSES
The demonstration included a display of 20 potato varieties representing multiple market classes inoculated with PVY-O, PVY-NWi, PVY-NTN, and a non-virus-inoculated control. The demonstration also showed the varieties inoculated with the PVY
continued on pg. 64
strain types that resulted from two separate planting dates (May 24 and June 3). This demonstration was an exceptional field tool for growers, potato certification inspectors, researchers, and students during the summer of 2022.
Through a collaborative effort between UW-Madison researchers Dr. Russell Groves, Dr. Amanda Gevens, and graduate student John Hammel (Plant Pathology Master of Science student), the plots were carefully photographed to record signature and unique symptoms, and tubers were harvested for further tuber observations and analyses. The results of this effort will be compiled and made available to our industry and research community to support the need for continued and accurate visual monitoring of PVY in potato systems. Directly above is information on the Potato Virus Initiative:
MOLECULAR DETECTION OF PVY
In support of visually detecting PVY infections, the use of molecular diagnostic methods to identify strains within our state is vital to the Wisconsin potato industry. Understanding PVY pressures allows for the development of management practices tailored to combat specific strains.
Dr. Kutay Ozturk, a post-doctoral research associate with the Department of Plant Pathology at UW-Madison, is working on developing a CRISPR-based assay to efficiently yet accurately detect biomarkers specific to PVY strains. To validate this assay, Dr. Ozturk is working with WSPCP staff to survey potato growing locations and then performing traditional PVY strain detection assays in comparison to the CRISPR-based method to validate this new method while compiling information on strain presence and distribution.
DORMANT TUBER TESTING
Recently, there has been a lot of interest in dormant tuber testing, specifically the benefits of this diagnostic method as the U.S. Department of Agriculture (USDA) APHIS (Animal and Plant Health Inspection Service) State National Harmonization Program works with seed potato certification programs to implement a necrotic virus management plan. Dormant tuber testing is exactly as it sounds, utilizing dormant tuber tissue to test for pathogens, which allows for earlier distribution of certification results, the ability to test for multiple pathogens in a single sample, the detection of non-visual pathogens and the potential for cost reductions. However, this is a new area of research, so questions such as “Do we still need a winter certification grow-out?”, “How accurate is dormant tuber testing?” and “What kind of labor requirements are needed?” are being asked. Various research projects are underway to address these questions, and we are excited to explore the dormant tuber research projects outlined further in this article.
PVY IMMUNOCAPTURE
A diagnostic research component of a larger SCRI-funded grant to develop a PVY Immunocapture PCR (PVY IC-PCR) assay has been underway for several years. This project is spearheaded by Dr. Nina Zidack and Dr. Alice Pilgeram at Montana State University. This experimental diagnostic method focuses on utilizing techniques from the traditional ELISA assay where PVY-specific antibodies are used to capture PVY. For dormant tubers, four cores are taken from each tuber in a 400-tuber sample, mashed in 10-tuber composite samples and then loaded into a coated PCR plate. For IC-PCR, the virus is captured in each well of the PCR plate by a specific antibody, and a real-time PCR assay can be performed directly using PVY-specific primers. Currently, only PVY is detectable via IC-PCR, but ongoing research is focused on expanding the number of viruses that can be detected using this testing method.
NATIONWIDE CROWD SOURCING
A nationwide “Crowd Sourcing” project spearheaded by Jason Ingram and Dr. Melanie Filiatrault of the USDA Agricultural Research Service is examining the efficacy of testing
A Wisconsin Seed Potato Certification Program staff member loads a PVY IC-PCR plate with a multi-channel pipette.
tuber lots using an FTA (Flinders Technology Associate)-card PCRbased assay to detect PVY across all U.S. seed potato growing states, including Wisconsin.
continued on pg. 66
Four cores from each tuber in a 400-tuber sample will be extracted and smashed onto FTA cards in 25-tuber composite samples. The FTA cards can easily be stored during the processing period, and when convenient, sent to a private testing facility. Laboratory results will be compared to the traditional certification winter grow-out PVY visual and molecular results for each certification lot. It is exciting to see such a large-scale, proof-of-concept effort focused on dormant tuber testing with many anxiously awaiting results.
NECROTIC TUBER VIRUS
Dr. Ozturk is currently developing and evaluating potential detection methods for rapid and efficient detection of necrotic tuber viruses. Focus is being placed on ensuring these detection methods have the
A diagnostic sample is collected by punching small sections of an FTA card impregnated with tuber sap. The presence of PVY will be detected via a PCR-based assay.
potential to detect other pathogens such as bacteria and fungi in a single sample. He has confirmed the presence of PVY from asymptomatic potato leaves utilizing a nanopore sequencingbased approach and is currently working to optimize and increase the throughput of this method to detect multiple necrotic tuber viruses from plant tissues. Once the method is optimized, it will be utilized in collaboration with the WSPCP to generate information on the biology of emerging tuber necrotic viruses and disseminate critical information on tuber necrotic viruses needed for Wisconsin to maintain its status as an elite producer of certified seed potatoes. We aim to provide updates of our ongoing collaborative projects at upcoming Grower Education Conferences. If there are any questions, please contact our authors for more information. We appreciate the collaboration of our grower and industry partners to advance our goal of ensuring the cleanest seed potatoes for Wisconsin.
Review Agribusiness Contracts Before Signing
Amy Ebeling Kelly Wilfert
There are important terms and key issues to keep in mind before agreeing to any contract.
By Attorneys Amy Ebeling and Kelly Wilfert, Ruder Ware, L.L.S.C.
The most popular varieties of these world-class hybrids are going fast.
Wisconsin’s Highest Yielding Corn and Soybean Varieties Are At
Visit with Wayne, Ann, Julie and Sammi today to secure the top performing hybrids. Don’t delay, these seeds are growing fast!
www. Jay-Mar.com Plover (715) 341-3445 800-236-2436
As year-end approaches, many farmers are already looking ahead to 2023, thinking about what commodities they will grow, inputs that will be needed, new equipment that might be justified, or a new value-added venture they might begin. As part of these transactions, agricultural producers are often asked to sign written contracts. Although the content of the contracts may vary, there are several issues that typically apply to any business contract regardless of subject matter. This article summarizes a few important terms to keep in mind before signing a contract.
Identify the Parties
The first step in considering any
Above: Any business contract should clearly identify which individual or business entity is involved, whether it is the farm or the producer in his or her individual capacity.
business contract is to think carefully about the parties—the people or businesses who are entering into the agreement. Each producer may conduct business as a sole proprietor, partnership, limited liability company, corporation, or even in trust.
Any business contract should clearly identify which individual or business entity is involved, whether it is the farm or the producer in his or her individual capacity. Remember to carefully consider the counterparty and review the potential risks of contracting with the other party, including its reputation, creditworthiness, and general reliability. A party’s creditworthiness may affect its ability to pay amounts owed as well as perform its non-monetary obligations under the contract.
Clearly Describe the Goods or Services
Many contractual disputes relate to what goods or services were to be provided. A well-drafted business contract describes the goods being sold or services being provided in as clear and accurate a manner as possible to avoid the risk of future disagreements. All important details about quality, quantity, and timelines should be included in the written contract and only be subject to amendment by mutual agreement of both parties. It’s best not to rely on verbal assurances, agreements to agree at a future date, or a handshake deal. Read the contract carefully before signing to ensure it matches the verbal agreement as you understand it. The written agreement will usually take precedence if there’s uncertainty later.
– Attorneys Kelly Wilfert and Amy Ebeling,
Ruder Ware, L.L.S.C.
FOCUSED ON AG. FOCUSED ON YOU.
A cooperative providing customized financing and financial services for farmers, ranchers, and agribusinesses: • Operating, Machinery, and RE Loans • Rural Home & Recreational Land Loans • Insurance (MPCI, Hail, DRP, Life) • Cash Patronage Program • Farm Accounting & Tax Preparation
Marshfield 800-324-5752
Medford 800-324-5753 Stevens Point 800-324-5754
Thorp 800-324-5758
Wausau 800-324-5751
AgCountry.com
continued from pg. 69
Define Price and How Payment Will Be Made
The economic terms are obviously an important section of any business contract. A contract should clearly define how the price is determined. For example, is it a fixed sum or a variable amount?
The contract should also clearly outline how payment is to be made (cash, check, wire transfer) and when it’s due (upon signing the contract, completion of the deal, or another timeline).
Also note whether the payment terms will or should include concepts such as installment payments, security deposits, delivery costs, or a payment schedule.
Consider Contingencies or “Conditions Precedent” to Performance
Many contracts incorporate some form of contingency into their terms. A good example is making an offer to purchase a new home contingent on the sale of an existing home.
If a contract includes contingencies—sometimes called “conditions precedent”—be sure that, to the extent possible, the outcome can be controlled, and the conditions satisfied so both parties are obligated to perform under the terms of the contract.
P O Box 267, Monte Vista, CO 81144
ColoradoCertifiedPotatoGrowers.com Lyla@ColoradoCertifiedPotatoGrowers.com (719) 274-5996 Carefully review the contingencies included to determine if you are willing to accept them.
In 2020 and the years since, many producers learned about contingent pricing the hard way. It is wise to consider which items are true contingencies and which act as options for a party to unilaterally amend the terms.
Give Thought to What Happens if Things Go Wrong
At the onset of any business relationship, most people assume that everything will end well. Unfortunately, deals do not always go as planned.
Any lawyer will say it’s more effective and less expensive to address issues at the front end in a clearly written contract than to address them in a dispute-resolution process after things have gone wrong.
When considering a potential contract, review what happens if things go wrong. What, if any, financial loss could be incurred, and which party will bear that loss?
The fine print of many contracts can contain limitations of liability that may not be appropriate in all circumstances.
Review Schedule
The effective date of an agreement can sometimes be important, as can the other time-related provisions. Consider if it’s a contract that will last for a particular period—a term—and how that term may be renewed.
If the contract calls for a one-time delivery of goods or services, be
sure the agreed upon timeline is documented. As part of an industry where receiving a week’s delay can change the outcome of the season, a clear timetable is essential for any agribusiness contract.
Evaluate Termination Provisions
An important aspect of the “What happens if things go wrong?” analysis is to consider how each party can end the contract.
If, for example, the counterparty fails to perform, a producer needs to consider if he or she can cancel the contract for any reason (without cause) or for what constitutes cause to terminate (failure to deliver by a certain date, low quality of service, or other considerations).
Cause can be difficult to prove. A termination right can be extremely important in making sure that an agribusiness is not unreasonably tied to a problematic counterparty who is not performing.
Failure to consider key issues and avoid these common pitfalls during contract negotiations may result in unforeseen obligations, unintended breaches, or negative financial consequences after signing a contract.
An ounce of prevention is often worth a pound of cure, and agribusiness owners should keep the above issues in mind throughout the process to help avoid negative outcomes during the season.
Top Right: A well-drafted business contract describes the goods being sold or services being provided in as clear and accurate a manner as possible to avoid the risk of future disagreements.
Dagen Heritage Farms
EST. 1882
SEED POTATOES VIGOR
MINNESOTA SEED POTATOES
VARIETIES Umatilla Russet Burbank Lamoka Modoc Red Norland Dakota Russet FY1, FY2, FY3
Isolation - Sanitation Dedication - Winter-Tested
Call Justin Dagen Today!
Karlstad, MN • (218) 686-1734 • jdagen@wiktel.com
