Tomato Graft Hybrids

Figure 10.
1) Fruit from the control plant 'Rosso Grosso' (Pink Giant)
2) Cluster from the control plant of a tomato from Mexico No. K-1014
3 and 4) Clusters from plants of the first seed generation from an innoculation of a tomato from Mexico No. K-1014 (stock) with 'Rosso Grosso' (scion). Seed from late shoots of stock.
From Iarovizatsiia: A. A. Avakian and M. G. Yemred

Fig. 51. The pot on the left contains a No. K-1014 tomato plant from Mexico. The pot on the right, a 'Rosso Grosso' variety tomato plant. The middle pot has a plant of the first seed generation vegetative hybrid obtained from grafting 'Rosso Grosso' (the scion) on a No. K-1014 tomato (stock).
   The seeds for the sowing were taken from the fruit that developed on a shoot of the No. K-1014 stock. The picture shows that the fruit of the vegetative hybrid are considerably larger than those of the No. K-1014 tomato. In shape some of the fruits of the hybrid resemble the fruits of No. K-1014, others are almost like the 'Rosso Grosso' fruits.
From Lysenko's Agrobiology

Figure. III. 
Top left: Fruit of unmodified black nightshade (Solanum nigrum L.);
Top right: From unmodified bush of a tomato "Best of All".
Bottom row: Two fruit from bushes of the first seed generation vegetative hybrid "Best of All" (scion) and Solanum nigrum L. (stock). Seed from tomato "Best of All".
Figure by G.V.Vinogradov, Iarovizatsiia

In experiments conducted by E. P. Khazina, a postgraduate at the Institute of Selection and Genetics (Odessa), a cutting from a young 'Humbert' tomato plant was grafted on to a nightshade. From the fruit of these tomatoes seeds were taken and planted, and cuttings from the resulting plants were also grafted on to the nightshade. The seeds from each fruit of the second 'Humbert' grafting on the nightshade were planted separately. It was found that some of the plants from one and the same fruit produced fruit of a shape that differed sharply from the 'Humbert'. They were not elongated but round, i.e., the shape of the nightshade stock. (Agrobiology, p. 289)

Vegetative hybrids obtained by grafting tomato on nightshade (Solanum) and Lycium barbarum are now undergoing fundamental varietal trials. It may already be said that, as far as early-maturation is concerned, these vegetative hybrids are not inferior, or are even superior, to the earliest maturing tomato varieties. As regards yield (as may be judged by the number of fruits), these hybrids are considerably superior to the early-maturing varieties. The vegetative hybrids are distinguished by one valuable quality—they show no tendency whatever to shed buds or ovaries, whereas shedding of buds and ovaries in one degree or another is characteristic of all known varieties of tomato. (M. A. Olshansky, 1948)

Plasticity of vegetative hybrids. Vegetative hybrids deserve particular attention in studies of so-called unstable heredity. They are a very plastic material for further building up new varieties through the influence of growing conditions. Thus, a tomato variety 'Best of All' grafted on a nightshade (a weed) gave changes in a series of characters. A vegetative hybrid has been obtained. Not one of the characteristics of the tomato variety 'Best of All' was preserved intact. Com. A. A. Avakian selected plants which when propagated by seeds give fruits with much improved taste qualities. The fruit shape of the tomato variety used in grafting has also changed. Forms derived from the vegetative hybrids acquired first, the early maturity of the nightshade, and then, influenced by growing conditions, became even more early. The resulting cultivated tomatoes are the earliest known to us. When seeds were sown outdoors in the soil in early May at the experimental base of the V. I. Lennin All-Union Academy of the Agricultural Sciences at Gorki-Leninskie (near Moscow), they gave in 1941 and 1942 a good maturation of fruits before the autumn frosts. (Lysenko: Heredity and its variability).

...long before the war, at the Academy's experimental base at Gorki-Leninskiye, graftings of tomatoes were made on solanum. As a result of the grafting the fruits not only of the hybrids but also of their seed progeny acquired a rather pleasant piquant flavour. The seed progeny obtained from these vegetative hybrids were so abundant that their fruits were sent to the local cooperative store for sale. People from surrounding villages, who apparently got to like the piquant flavour of the hybrid fruits, used to come to the store and simply say: "Weigh me a kilogram of vegetative hybrids." These were plain common folk, who appreciated the tomatoes for their taste, and not for their name. (I. I. Prezent, 1948)

According to George Ball:
"That Mr. Shifriss' father had immigrated to what would become Israel from Odessa in Ukraine was not irrelevant in the development of the Big Boy, whose genetic heritage remains a 'trade secret,'" Ball said. "Some of the greatest-flavored tomatoes are from the Ukraine, like the Black Krim, a dark purply-green tomato. So when you talk about tomatoes from the Ukraine and the mystery of the Big Boy, you're getting warm."

*Don Chapman at Bio-Organics
Rombough: Mychrrhizal Fungii
One of Mr. Chapman's* customers, a Master Gardener, reported the yield of his tomatoes doubled with fungi, while ripening time was as much as a week earlier. He also said the tomatoes tasted much better.

CybeRose note: It may be that one aspect of the "vegetative hybridization" is to transfer the ability to form symbiotic relationships with the local mycorrhizal fungi. This is known to occur in beans with regards to nitrogen-fixing bacteria. See Richmond (1926), Hofmann (1927)