DESIGNING SCHEMES FOR SEED PRODUCTION OF SPRING RAPE F1 HYBRIDS BASED ON CMS

As the result of the research conducted in 2018–2020 at the All-Russian Rapeseed Research Institute, a scheme of primary seed farming of self-pollinated lines and F1 hybrids of spring rape has been developed, over 45 varieties have been created, including self-pollinated lines, simple interline and three-line hybrids. A comparative appraisal of spring rape inbred lines (female parents) and hybrids of the two most common systems of cytoplasmic male sterility (CMS) – Polima (LHS-1, LMS-1, LMS-2) and Ogura (LCS-4, LCS-5, LCS-6), was made. Yield traits distinctiveness in simple sterile hybrids of Polima and Ogura types was studied; it has been asserted that when compared to inbred maternal lines the traits predominate in hybrids, the indices are higher by 24.8% in the hybrids based on sterile Ogura cytoplasm and by 10.7% in the hybrids on sterile Polima cytoplasm. In our studies, self-pollinated lines, the maternal components of the hybrids, are inferior to the hybrids in terms of crude fat content in seeds, it is 6.5% lower than in the hybrid forms for the CMS Pol system and 17.3% lower for the forms of the CMS Ogu system. It was determined that the seed yield of CMS systems hybrids of Ogura type is on average 22.0% higher than the seed yield of Polima hybrids. The starting material for primary seed production of rapeseed hybrids based on CMS has been developed.

Introgressing Cold-tolerant Ogura Cytoplasm from Rapeseed into Pak Choi and Chinese Cabbage

Cold-tolerant, Ogura male-sterile, somatic hybrid rapeseed (Brassica napus L.) lines were used as maternal parents in two independent introgression experiments. In one experiment, an atrazine-sensitive B. napus (aacc) somatic hybrid was crossed directly with a male-fertile pak choi (B. campestris Chinensis Group, aa) accession. Allotriploid (sac) progeny were then backcrossed to the recurrent pak choi parent. Forty-five percent of the progeny from the first backcross were determined to be diploids (aa). In the other experiment, an atrazine-resistant B. napus somatic hybrid was crossed first to a bridge line. Three additional backcross generations to Chinese cabbage (B. campestris Pekinensis Group) resulted in Chinese cabbage resistant to black rot (Xanthomonas campestris pv. campestris). These materials may be useful for production of B. campestris hybrid vegetable seed.