AUTHOR=Sharma Brij B. , Kalia Pritam , Singh Dinesh , Sharma Tilak R. 

TITLE=Introgression of Black Rot Resistance from Brassica carinata to Cauliflower (Brassica oleracea botrytis Group) through Embryo Rescue

JOURNAL=Frontiers in Plant Science

VOLUME=8

YEAR=2017

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2017.01255

DOI=10.3389/fpls.2017.01255

ISSN=1664-462X

ABSTRACT=<p>Black rot caused by <italic>Xanthomonas campestris</italic> pv. <italic>campestris</italic> (<italic>Xcc</italic>) is a very important disease of cauliflower (<italic>Brassica oleracea botrytis</italic> group) resulting into 10–50% yield losses every year. Since there is a dearth of availability of resistance to black rot disease in <italic>B. oleracea</italic> (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<sub>1</sub>) were generated between cauliflower “Pusa Sharad” and Ethiopian mustard “NPC-9” employing <italic>in vitro</italic> embryo rescue technique. Direct ovule culture method was better than siliqua culture under different temperature regime periods. Hybridity testing of F<sub>1</sub> inter-specific plants was carried out using co-dominant SSR marker and <italic>Brassica</italic> B and C genome-specific (DB and DC) primers. Meiosis in the di-genomic (BCC) interspecific hybrid of <italic>B. oleracea botrytis</italic> group (2<italic>n</italic> = 18, CC) × <italic>B. carinata</italic> (2<italic>n</italic> = 4x = 34, BBCC) was higly disorganized and cytological analysis of pollen mother cells revealed chromosomes 2<italic>n</italic> = 26 at metaphase-I. Fertile giant pollen grain formation was observed frequently in interspecific F<sub>1</sub> hybrid and BC<sub>1</sub> plants. The F<sub>1</sub> inter-specific plants were found to be resistant to <italic>Xcc</italic> race 1. Segregation distortion was observed in BC<sub>1</sub> generation for black rot resistance and different morphological traits. The At1g70610 marker analysis confirmed successful introgression of black rot resistance in interspecific BC<sub>1</sub> 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.</p>