Association of single-nucleotide polymorphisms in resistance gene sequences with blackleg disease in oilseed rape (Brassica napus)
A broad variation forresistance to blackleg disease caused by Leptosphaeria maculans (anamorph Phoma lingam) is present in the Brassica napus gene pool, however due to the quantitative nature of the resistance it is difficult to develop effective selection markers. This project aims at detection and exploitation of genetic diversity of resistance gene candidates associated with blackleg resistance in B. napus via association studies between resistance data and single nucleotide polymorphism (SNP) haplotypes in a core set of 50 diverse oilseed rape genotypes. Resistance gene analogue (RGA) sequences have been amplified in resistant and non-resistant B. napus genotypes using degenerate primers for resistance gene motifs (TIR, NBS, LRR). In addition to these anonymous RGA sequences, further primer combinations were developed using potential resistance gene candidates (RGCs)selected from publicly available cDNAs derived from the B. napus defense reaction to inoculation with L. maculans.Sequence-independent SNP-detection using specific primers was performed in the genotype core set via BESS-T (base-excision sequence scanning), and the SNP data were used for association studies with L. maculans resistance/susceptibility data from field and greenhouse tests. Cloning of RGA and RGC sequences with significant associations to resistance data allowed development of locus-specific PCR primers, so that sequences of the relevant loci could be compared in the genotype set and verified in independent materials. The resulting SNP markers for haplotypes associated with quantitative resistance loci will be useful not only for marker-assisted selection, but also for identification of new resistance sources in the broader B. napus gene pool.
Rapeseed Brassica napus blackleg Leptosphaeria maculans SNP association study resistance genes
Katrin Link Wolfgang Friedt Rod Snowdon
Department of Plant Breeding, Research Centre for BioSystems, Land Use and Nutrition, Justus Liebig University, Heinrich-Buff-Ring 26-32, 35392 Giessen, Germany
国际会议
第十二届国际油菜大会( The 12th International Rapeseed Congress)
武汉
英文
1348-1350
2007-03-26（万方平台首次上网日期，不代表论文的发表时间）