title: Genetics and Molecular Mapping of Black Rot Resistance Locus Xca1bc on Chromosome B-7 in Ethiopian Mustard (Brassica carinata A. Braun).
abstract: Black rot caused by Xanthomonas campestris pv. campestris (Pam.) Dowson is the most destructive disease of cauliflower causing huge loss to the farmers throughout the world. Since there are limited sources of resistance to black rot in B. oleracea (C genome Brassica), exploration of A and B genomes of Brassica was planned as these were thought to be potential reservoirs of black rot resistance gene(s). In our search for new gene(s) for black rot resistance, F2 mapping population was developed in Brassica carinata (BBCC) by crossing NPC-17, a susceptible genotype with NPC-9, a resistant genotype. Out of 364 Intron length polymorphic markers and microsatellite primers used in this study, 41 distinguished the parental lines. However, resistant and susceptible bulks could be distinguished by three markers At1g70610, SSR Na14-G02 and At1g71865 which were used for genotyping of F2 mapping population. These markers were placed along the resistance gene, according to order, covering a distance of 36.30 cM. Intron length polymorphic markers At1g70610 and At1g71865 were found to be linked to black rot resistance locus (Xca1bc) at 6.2 and 12.8 cM distance, respectively. This is the first report of identification of markers linked to Xca1bc locus in Brassica carinata on B-7 linkage group. Intron length polymorphic markers provided a novel and attractive option for marker assisted selection due to high cross transferability and cost effectiveness for marker assisted alien gene introgression into cauliflower.
authors.affiliation: Division of Vegetable Science, ICAR-Indian Agricultural Research Institute, New Delhi, India.
authors.forename: Brij Bihari
authors.initials: BB
authors.lastname: Sharma
authors.affiliation: Division of Vegetable Science, ICAR-Indian Agricultural Research Institute, New Delhi, India.
authors.forename: Pritam
authors.initials: P
authors.lastname: Kalia
authors.affiliation: Division of Seed Science & Technology, ICAR-Indian Agricultural Research Institute, New Delhi, India.
authors.forename: Devendra Kumar
authors.initials: DK
authors.lastname: Yadava
authors.affiliation: Division of Plant Pathology, ICAR-Indian Agricultural Research Institute, New Delhi, India.
authors.forename: Dinesh
authors.initials: D
authors.lastname: Singh
authors.affiliation: ICAR- National Research Centre on Plant Biotechnology, New Delhi, India.
authors.forename: Tilak Raj
authors.initials: TR
authors.lastname: Sharma
mesh_terms: D002874:Chromosome Mapping; D020090:Chromosome Segregation / Q000235:genetics; D032461:Chromosomes, Plant / Q000235:genetics*; D003433:Crosses, Genetic; D060467:Disease Resistance / Q000235:genetics*; D017343:Genes, Plant; D008040:Genetic Linkage; D056426:Genetic Loci; D005819:Genetic Markers; D005838:Genotype; D009149:Mustard Plant / Q000235:genetics* / Q000276:immunology / Q000382:microbiology; D010641:Phenotype; D010935:Plant Diseases / Q000235:genetics* / Q000276:immunology / Q000382:microbiology; D016959:Xanthomonas campestris / Q000502:physiology*
chemical_list: D005819:Genetic Markers