Introgression of Black Rot Resistance from to Cauliflower ( Group) through Embryo Rescue.

Black rot caused by pv. () is a very important disease of cauliflower ( group) resulting into 10-50% yield losses every year. Since there is a dearth of availability of resistance to black rot disease in (C genome), therefore exploration of A and B genomes was inevitable as they have been reported to be potential reservoirs of gene(s) for resistance to black rot. To utilize these sources, interspecific hybrid and backcross progeny (B) were generated between cauliflower "Pusa Sharad" and Ethiopian mustard "NPC-9" employing embryo rescue technique. Direct ovule culture method was better than siliqua culture under different temperature regime periods. Hybridity testing of F inter-specific plants was carried out using co-dominant SSR marker and B and C genome-specific (DB and DC) primers. Meiosis in the di-genomic (BCC) interspecific hybrid of group (2 = 18, CC) × (2 = 4x = 34, BBCC) was higly disorganized and cytological analysis of pollen mother cells revealed chromosomes 2 = 26 at metaphase-I. Fertile giant pollen grain formation was observed frequently in interspecific F hybrid and BC plants. The F inter-specific plants were found to be resistant to race 1. Segregation distortion was observed in BC generation for black rot resistance and different morphological traits. The At1g70610 marker analysis confirmed successful introgression of black rot resistance in interspecific BC population. This effort will go a long way in pyramiding gene(s) for resistance against black rot in Cole crops, especially cauliflower and cabbage for developing durable resistance, thus minimize dependency on bactericides.