CREATION OF ORYZA SATIVA L. DOUBLED HAPLOYDS WITH THE Pi-B GENE OF RICE BLAST RESISTANCE IN THE RUSSIAN FAR EAST

The study was conducted with the aim of obtaining doubled haploids with the Pi-b gene for rice Oryza sativa L. breeding. As a result of hybridization between Far Eastern varieties and the Oxy 2x sample (carrier of the Pi-b gene), 13 F1 hybrids of six hybrid combinations were created: Sadko×Oxy 2x, Lugovoy×Oxy 2x, Darius 23×Oxy 2x, Almaz×Oxy 2x, doubled haploid (Don 4237×Dolinny)×Oxy 2x, Khankaisky 429×Oxy 2x. In vitro androgenesis technology was used to transfer the original F2 donor plants to a constant homozygous state. 35 hybrid plants carrying the resistance allele of the Pi-b gene were preliminarily selected. 10246 rice anthers were introduced into the in vitro culture. Callus formation was observed in 25 of 35 F2 hybrids. The highest callus formation values were noted in the hybrid plants Lugovoy×Oxy 2x - 9.33 % and Khankaisky 429×Oxy 2x - 27.50 %, and on average for the entire sample it was low - 2.45 %, which is not typical for Far Eastern genotypes. Regeneration was observed on calli of seven rice hybrids of four hybrid combinations: Darius 23×Oxy 2x, Sadko×Oxy 2x, Khankaisky 429×Oxy 2x and Lugovoy×Oxy 2x. Based on the results of PCR analysis, 33 plants with the resistance allele of the Pi-b gene were selected from 63 rice doubled haploids. 44 lines of doubled haploids were sown on the vegetation plot, three of which did not sprout. The collection sample Oxy 2x, being itself with a strong attachment of the grain to the panicle axis, interacting with the loci of other varieties responsible for the strength of the grain attachment, produces a phenotypes that fall of to varying degrees in the homozygous state in doubled haploids: 11 lines with an average degree of shedding, 30 lines with strong shedding. Thus, the total yield of the initial breeding material for subsequent selections in field conditions is very limited and unpromising due to the falling of the grain.