Development and Characterization of Wheat-Rye Hybrids Produced by Meiotic Restitution.

Abstract: The nature of the formation of fertile progenies of F2 and F3 generations of wheat-rye hybrids obtained as a result of meiotic restitution using the Saratovskaya 29 variety (C29 x R) and the wheat-rye substituted line 1Rv(1A) (1Rv (1A) × R) was studied. The karyotype analysis of the F2Triticum aestivum L. cv. Saratovskaya 29 × Secale cereale L. var. Onochoyskaya (S29 × R) hybrid using C-banding revealed 56 chromosomes; among them were 42 wheat chromosomes and 14 rye chromosomes. The karyotype of the F2 1Rv(1A) × R hybrid contained 46 chromosomes, of which three pairs of rye chromosomes 1R1R4R4R2RL2RL, 1R1R replaced the chromosomes 1A1A, and 2RL2RL and 4R4R were additional to the wheat chromosomes. In the F3 generation of S29 × R hybrids, the octoploid number of chromosomes with aneuploidy of single rye and wheat chromosomes was preserved, while in the 1Rv(1A) × R hybrids the number of chromosomes varied from 42 to 49, but in most plants 2n = 46 was retained. Meiosis of the F3 1Rv(1A) × R hybrids was more stable than that of the S29 × R hybrids. The average number of univalents in 1Rv(1A) × R hybrids was 1.54 ± 0.17, which was significantly lower than in S29 × R hybrid progenies (2.56 ± 0.23 and 2.07 ± 0.27). The F3 С29 × R and 1Rv(1A) × R hybrids were characterized by the variability in the seed set and 1000-grain weight. On average, С29 × R plants produced a smaller number of grains with but larger size than 1Rv(1A) × R plants, forming more grains with lower 1000-grain weight. The obtained results indicate the influence of the substitution 1Rv(1A) on the reorganization of hybrid genomes. [ABSTRACT FROM AUTHOR]