Оptimization of cellular technologies <i>in vitro</i> for accelerated production of rice <i>Oryza sativa</i> L
The research has been carried out to study the responsiveness of genotypes and optimize the two-stage technology of rice anthers culture in vitro in relation to 8 cultivars of crossing of different pericarp coloration and amylose content in the grain (5 cultivars with colored pericarp and 3 white-grained cultivars of Russian breeding), increasing the induction of morphogenic calluses, the formation of haploid embryos and regenerating plants for the selection of new generation cultivars intended for functional nutrition. It was revealed that the anthers of the basal parts of the panicle contained pollen at all single-core stages of development, including early, middle and late, and showed a higher frequency of callus induction than in the middle and upper parts. At the early stages of microspore development, pollen dimorphism was noted: the presence of normal and embryogenic (competent) microspores in the anthers, which give rise to neoplasms in in vitro culture. Due to the optimization of exogenous factors, it was possible to stimulate the induction of callus for weakly responsive genotypes. The optimal terms of cultivation of newly formed calluses on callus and regeneration media to ensure maximum yield of regenerants have been identified.