Genetics Today: Proceedings of the XI International Congress of Genetics (1963) p. 235
13.77. New Methods in Cotton Hybridization.
D. V. Ter-Avanesyan (U.S.S.R.)

Achievements in biological science reached in the last decade are well known. It should be noticed, however, that as profound is our knowledge with regard to a living cell, so poor it is in the field of biology of pollination and fertilization. The experimental data remain unexplained so far, and they are strictly empirical. Here are some interesting results of a long period of our work at the Central Asia Experimental Station of the All-Union Research Institute of Plant Breeding. There was a task to work out the method of cotton hybridization using the pollen of heterochromosomic species and even of genera of Malvaceae family.

As it is known, in the case of hybridization of G. hirsutum L. cotton species with G. herbaceum L. and G. arboreum L. (African-Asiatic species) having twice less chromosomes in their cells, pollen tubes of the latter, as a rule, do not fertilize even if they reach embryo sac of diploid form. At the same time the pollen of the Malvaceae family (Hibiscus esculentus, H. rosa sinensis, H. cannabinus and Malva neglecta) does not germinate on the cotton stigma at all.

But in spite of the evident genetical incompatibility of chromosomic gametes we succeeded in using them when working out two breeding methods. The first method is as follows: at the growing period of maternal cotton there were 2-3 buds left on the plant, the rest being removed. This method stimulated the accumulation of nutrients in flowers. 10-20 pollen grains were placed on the stigma of emasculated flower followed by unlimited pollination with the pollen of a paternal form (in this case of an alien species) for 3 hours.

The second method with similar results was the following: in that very evening emasculated flowers were pollinated with unlimited quantity of paternal pollen. Next day unlimited quantity of parental pollen was again placed on the stigma of the same flower, and at noon (about 20 hours after emasculation) there was pollination with the mixture of paternal and maternal pollen in different amounts.

The first and second generations from seeds developed by the described method, gave some interesting plants. The progeny considerably differed from maternal plants. It got the characters of non-crossing cotton species and changed completely its qualitative and quantitative characteristics being affected by the pollen of Malvaceae plants. These characters became hereditarily fixed, and they were transmitted to progenies. The suggested methods can be used for cotton hybridization. They will improve our possibilities of using diversified Gossypium genus in cotton hybridization.

Cotton Bibliography

Pollen Mixtures