MQ 1 - The graft in succulent plants

n. 1

The graft in succulent plants and in particular in Cactaceae

by Andrea Cattabriga

Published in 1983 on “Piante Grasse”, issue # 3

MONDOCACTUS

QUADERNI

Titolo

MONDOCACTUS QUADERNI n. 1

Editorial

The graft in succulent plants and in particular in Cactaceae

Dear reader,

by Andrea Cattabriga.

Text and pictures by the author.

Originally published on Piante Grasse, Vol III, n° 3/4, Set-Dic 1983, pp. 53-56.

Digital repring November 2014. www.mondocactus.com info@mondocactus.com

the series “Mondocactus notebooks” collects a renewed edition of the articles devoted to the succulent plants that I produced from 1983 until today.

The text of the articles was deliberately preserved in its original form, so any errors in grammar and concept have not been corrected. For this occasion was also produced this version of the English text. I apologize for the low quality of the translation, accomplished with the tools available on the internet, but its only purpose is to make the least understandable text to an international audience.

Reading the various items you can appreciate significant variations of the style adopted from time to time, due to both a gradual maturity of expression, and the need to adapt the article to the kind of publication in which it was intended, it was a magazine of an association of amateurs, or a commercial journal.

The purpose of this project is to integrate the general information available on the mondocactus website pages with free downloadable documents on specific topics.

This work is distributed under Creative Commons License Attribution-NonCommercial-NoDerivatives 4.0 International.

2

good reading Andrea Cattabriga

The graft in succulent plants and in particular in Cactaceae

I

n this article and in the tables that accompany it, I describe everything I’ve seen and heard about the technique of grafting of cacti and succulents. These news I have accumulated in a year or more; sought both to school (in my fourth year of the Agricultural Technical Institute in Bologna), both at nurseries and specialist growers, beginners and professionals. I experienced long since learned, without making me break down the early failures and now I can say I have a minimum of experience.

Generally the grafting technique has as its goal to the root of a plant a bud or a branch of a different species, of which you want to improve the growth.

This type of asexual multiplication (seedless) is possible in only plants that belong to the class of Dicotiledones, which are in fact provided by the “cambium”, a growth tissue (= plant cells in active multiplication) that forms a ring of conductive vessels. This “cambium” produces woody vessels inward and sieve tubes verses the outside. While the first bring the water (raw sap) absorbed by the roots to the photosensitisers tissues, the seconds distribute it, so enriched with useful substances in those tissues that need it.

Just the existence of this so active fabric allows the weld in the conduction system of a plant with that of another; from this depends the success of the grafting.

In Monocotyledons, the class to which they belong Agave, Haworthia and other succulents, there is no change. The conducting tissues are collected 3

in small bundles scattered throughout the trunk.

For this the graft is unlikely.

Between the Dicotiledones, plants must show certain biological affinity. This is the compatibility between plants that belong to the same families, such as Cactaceae, Euphorbiaceae, Apocynaceae, Asclepiadaceae etc.

In practice, the graft is used for various reasons, such as: save the healthy part of plants partially rotting; provide a robust root system in plants particularly sensitive or those more reluctant to issue roots spontaneously; stimulate growth in plants slow or tillering in those solitary. It is also necessary in order for the maintenance and propagation of plants showing particular mutations, such as those lacking chlorophyll (Hybotan) and the crested or monstrous.

The graft in practice

The plant is said to be grafted ‘scion’, ‘subject’ or ‘rootstock’ on which they will be engaged.

Usually used as a rootstock are the following species: Hylocereus spp., Trichocereus pachanoi, T. spachianus, T. macrogonus, Eriocereus jusbertii, Myrtillocactus geometrizans, Opuntia tomentosa, O. tomentella, O. bergeriana, O. ficus-indica, Cereus spp., Echinopsis spp. (Lately circulate seeds of Echinopsis hybr. specifically selected from rootstock), Pereskiopis sp.

For other succulents: The Apocynaceae are grafted on oleander; Asclepiadaceae on the tubers of Ceropegia or robust Stapelia; the Didiereaceae on

Alluaudia procera; on the Crassulaceae Crassula portulacea or Kalanchoë (tubiflora, daigremontana).

When I have to engage, if I can choose the subject in relation to the type of graft. it directs me so: • Young plants, or that do not measure more than 4mm in diameter: Pereskiopsis, Echinopsis from seed.

• Plants of one and two years, up to 1cm in diameter: Hylocereus, Myrtillocactus, Echinopsis.

• Adult plants, crested or monstrous: Trichocereus, Eriocereus, Myrtillocactus, Cereus, Opuntia.

• Plants to slow growth (Ariocarpus): Echinopsis.

• Epiphytic plants (Zygocactus, Epiphyllum): Pereskiopsis, Hylocereus.

At the time of the graft is better than scion and subject are in vegetation. Most suitable is the

spring-summer period.

You must use sharp blades and clean. For individuals and small slips are used razor blades. The cuts must be accurate, must not show steps or bumps.

It operates on the first rootstock (la, 2a, 3a, 4a), leaving a slice of this cut and resting on the wound which engages in order to prevent air from the drying out while operating on the scion. This is done on the subject join with movements back and forth to remove any air bubbles or excesses of mucilage.

Finally scion is positioned so as to match the circle of bundles at some point (more coincide better) as in the figures, 2c, 3c, 4c.

The adhesion of the subject with the scion is all the more assured as best maintains contact between the two parties. If for very small plants can be

4 – The graft in succulent plants and in particular in Cactaceae

a very simple pressure with the finger of a few minutes, not just as true for older plants, especially with vases very woody. For these plants, there are several methods: A, E) The pressure on the scion is provided by a microscope slide lightly weighted.

B) The graft is fixed by a patch or not scotch tape at the center.

C, D, G) Same function assumed by a rubber strip (air chamber bicycle maintained in tension by elastic blocking it to the subject or to the vessel. In (E) is used a steel plate elastic, stuck on a wooden support.

5) into the saddle you can use a clothespin or some plug to block the scion.

Splitted in the graft shown in Figure 7, may suf-

fice a thorn Cactus.

The scion, if cylindrical, can present cut longitudinally instead of transversely. The grafting is carried out as in 6 and 8.

The plants crested have a circle of vessels in the shape of an elongated oval, approximately like that Opuntia (11), whereby the graft can succeed best with this subject.

You can also take root on the subject the scion reversed (12). Taproots of Ariocarpus or Lophophora, or the lower part of the plant which has rotted the apex damage, if well taken root, a spontaneous emission of a number of branches in the graft.

It is also possible to plug more slips on branches of the same plant (9, 10).

5 – The graft in succulent plants and in particular in Cactaceae

If the graft is successful, the scion starts growing quickly. Opuntia and Hylocereus produce an initial over-development that swells the scion. Other subjects contain better growth.

With age, plants may grow slightly in volume. Generally lignify and can be reabsorbed by the scion that in some cases issues its roots.

Certain subjects, although easy to use are not so good. This is the case of Hylocereus. This epiphytic plant of tropical forests has a great development, ease of engraftment has made it suitable for largescale production on an industrial scale. Main flaw is that it is not resistant to temperature changes and that still does not tolerate the cold so that rots easily. Also can not stand even the dry too long: it blocks the vegetation of the scion and can dry out the roots and parts of the stem, that seems so eaten by rats. It is sensitive to rotting of the collar and into slot. The grafts with this subject I keep them in the greenhouse, where in a short time lead to great development the scion. Who went to Portici (Na) will have seen the big Melocactus the collection of the botanical garden, perhaps did not realize that there are grafted on this plant ‘difficult’ that occasion had assumed an almost cylindrical.

A shortcoming of certain Trichocereus own, is the emission of branches that grow within the shaft.

It can happen that these rarely come to light just below the graft. Even more rare is the case that the Trichocereus grow within the scion and that from this sbuchi at the apex, is therefore not a defect so recurrent as to affect the use of this subject.

It seems that the Opuntia tomentosa is sensitive to certain diseases, and some growers do not use it anymore.

Obstacles to the success of a graft can be: infections by fungi or bacteria, if you work with blades dirty or infected; formation of a film of mucilage which isolates the scion from the subject.

Also, if we make a ligature too close the tender flesh of the subject or the scion dent and rots (such as apples). If we make too wide, dehydrating the pulp retires forming a basin, which is detach the scion. Even for this, in addition to the transverse cut on the subject, using “rounding” the edge (1b, 2b, 4b).

The individual may or may not be freed. What is certain is that the roots have much force, especially if you can not operate in wet environments such as greenhouses.

Let me conclude by saying that I practice grafting only if really necessary. In fact I consider the best natural plant and complete in all its parts, that one is engaged; this may be lacking some features that make it unique, as tuberous roots and taproots.

Thank friends partners Carlo Zanovello, Ronco Antonio and Giovanni Pirotelli for helping me, even in practice, in my research. I hope I was clear enough for those willing to try themselves grafting and I apologize for any uncertainty or omissions.

Bibliography

GINNS, R .: Succulents, Edagricole, Bologna 1971 RIHA. J i SUBIK, R .: The Illustrated Encyclopedia of Cacti and Other Succulents, Octopus Books Limited, London 1981 LODI, G .: My succulents, Edagricole, Bologna 1979 CACTUS and SUCCULENT JOURNAL (US), Vol. 55, N ‘3, 1983

6 – The graft in succulent plants and in particular in Cactaceae