GENETIC AND GENOMIC APPROACHES TO IMPROVE PEANUT AND CORN RESISTANCE TO DISEASE AND AFLATOXIN CONTAMINATION
Location: Crop Protection and Management Research
Title: Genetic linkage map and QTL analysis of resistance to TSWV and leaf spots in peanut (Arachis hypogaea L.)
Submitted to: American Peanut Research and Education Society Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: June 1, 2011
Publication Date: June 24, 2011
Citation: Feng, S., Zhou, B., Jiang, T., Culbreath, A., Qin, A., Chen, C.Y., Holbrook Jr, C.C., Guo, B. 2011. Genetic linkage map and QTL analysis of resistance to TSWV and leaf spots in peanut (Arachis hypogaea L.). American Peanut Research and Education Society Abstracts. APRES annual meeting in San Antonio, TX. July 12-14, 2011.
The allotetraploid peanut genome assembly will be a valuable resource to researchers studying polyploidy species, in addition to peanut genome evolution and domestication other than facilitating QTL analysis and the tools for marker-assisted breeding. Therefore, a peanut linkage map will aid genome assembly, acting as an independent resource against which contig assembly can be validated. The objective of this study was to develop a comparative integrated map from two recombinant inbred line populations. A total of 4576 SSR markers from three sources: published SSR markers, newly developed SSR markers from ESTs and from BAC end-sequences were used for screening polymorphisms. Two CAP markers were also included to differentiate ahFAD2A alleles and ahFAD2B alleles. A total of 324 markers were anchored on this integrated map covering 1,352.1 cM with 21 linkage groups (LGs). Combining information from duplicated loci between LGs and comparing with published diploid maps, 7 homoeologous groups were defined and 17 LGs (A1 to A10, B1 to B4, B7, B8, and B9) were aligned to corresponding A-subgenome or B-subgenome of diploid progenitors. The primary phenotype evaluations conducted in 2009 and 2010 has demonstrated that a significant divergence among RILs of both populations was obvious. TSWV disease ratings ranged from 1 to 10 in both populations and the parental line Tifrunner was 3 and C20 was 7.4, and NC94022 was 2.4 and SunOleic 97R was 6.8 in 2009. Late leaf spot was the dominate disease in 2010 and the disease ratings ranged from 4 to 8, and 3.5 to 8 for T and S population, respectively, and the parental line NC94022 was 4.2, SunOleic 97R had 5.8 and Tifrunner had 3.5 and C20 had 7.7. The identified QTL may explain about 40% phenotypic variation for TSWV based on 2009 ratings.