Hereditary Constitution
T D Lysenko

On crossing Hostianum 0237, a winter wheat, with spring wheat 1160 and 1163 (the latter two wheats being full sisters), the seeds obtained were normal. At first sprouts normal in their external appearance developed from them. But when the third leaf appeared the first shrivelled up. As soon as the fourth appeared the second shrivelled up. All the time only the last two leaves remained alive on the plant. In the end the plant perished. Thousands of such plants were under experiment at one time or another and not one of them lived long enough to ear; all died. The Mendelist-Morganists would attribute such a phenomenon to the action of lethal genes. But they would have nothing to offer wherewith to combat this action. They would declare it fatal, irresistible, and would endeavour to show that in such cases there is only one solution: don't take for crossbreeding plant or animal organisms that have lethal genes. Yet a cross of the same combination, Hostianum 0237 and 1160, produced hybrids which vegetated splendidly in these very same greenhouses and yielded viable, nonperishable plants. The point is that one of the components (paternal form 1160) is a spring variety, but for two generations before crossing it was sown in Odessa, not in spring but in the autumn. Then a cross was effected. This proved sufficient to obtain viable offspring. A different rearing of wheat 1160 altered the plant's sex cells; hence the difference in the result of hybridization.

In other experiments made by A. A. Avakian castrated Hostianum 0237 plants were fertilized with a mixture of pollen of the Erythrospermum 1160 variety and of Hostianum 0237, the maternal form. The plants bred from the seeds obtained were of hybrid origin. They were spring plants while the maternal form was a winter plant. But these plants too proved viable, nonperishing. Thus the presence of pollen of the maternal form, in the case in question Hostianum 0237, influenced the result of fertilization with Erythrospermum 1160 pollen. The offspring obtained were not lethal, as is usual in such a cross, but viable.

Michurin, too, pointed out the expedience in certain cases of mixing pollens. By this means he succeeded in crossing species and genera which otherwise could not cross.