Zambriborshch I. Genetic improvement of segregating populations on the embryogenesis in vitro ability in maize anther and somatic tissue cultures.

The thesis is devoted to studying of the problem of maize population genetic improvement for the anther and somatic culture embryogenesis ability. As a one out of the possible ways of this problem solution the recurrent selection is analyzed for populations which include anther or somatic embryogenesis donors together with diverse types of the maize germplasm. It has been found that the recurrent selection of the best genotypes with these traits on the sporophyte ontogenesis stage gave real possibility to increase significantly the morphogenic productivity level in vitro culture and involve diverse types of maize germplasm to the in vitro technology based breeding process including unsusceptible to the in vitro culture genotypes. Genetic systems control peculiarities of in vitro traits, their impact on value agronomic performances and possibilities of crucial cultural factors optimization were found. Key words: maize, anther culture, somatic culture, recurrent selection, cultural factor optimization.