Submitted to: Georgia Peanut Commission Annual Research Project Report
Publication Type: Abstract Only
Publication Acceptance Date: 2/8/2006
Publication Date: 2/8/2006
Citation: Guo, B., Holbrook, Jr., C.C., Kvien, C., Culbreath, A., Ozias-Akins, P., He, G. 2006. Identification and characterization of molecular marker(s) associated with resistance to TSWV and leaf spots in peanuts [abstract]. 2006. Abstracts of Georgia Peanut Commission Annual Research Report, February 8, 2006, Tifton, GA. Interpretive Summary:
Technical Abstract: In peanut production areas in the southeastern U.S., tomato spotted wilt virus disease caused by tomato spotted wilt tospovirus (TSWV) has become more prevalent and more severe. TSWV has become a major limiting factor for many peanut producers and control methods are limited. Both early (Cercospora arachidicola) and late (Cercosporidium personatum) leaf spot diseases are also among the worst foliar diseases of the cultivated peanut. Our strategy is to develop peanut cultivars with resistance to these diseases by using marker-assistant breeding and selection. We have been characterizing and developing DNA polymorphic markers associated with the resistant traits in peanut lines resistant or susceptible to TSWV and/or leaf spots, and generating a segregating population to map/clone the resistant loci/gene(s). RILs (recombinant inbred lines) are derived from Tifrunner, Runner type and resistant to TSWV and leaf spots, and GT-C20, Spanish type and susceptible to TSWV and leaf spots but resistant to Aspergillus/aflatoxin, bacteria wilt and rust. We also screened peanut lines, 0013 and 448A (resistant) and GK7 and Coan (susceptible) for polymorphic DNA markers. The progress has been made (2006): 1. One segregating population has been made from the cross between Tiftrunner and GT-20 (a Spanish type), and 180 F4/5 have been reached. 2. Total 450 soybean SSR (simple sequence repeats) markers from soybean have been translated to peanut. Total 87 SSRs have been able to amplify peanut genomic DNA. 3. EST-based SSRs have been developed from peanut ESTs from 8 cDNA libraries. Over 2,000 ESTs have been sequenced from 2 cDNA libraries, Tiftrunner leaf tissues and 013 immature seeds. Total 1345 EST sequences have been deposited in GenBank (accession number CD037499 to CD038843), and 400 unigenes have been generated from these ESTs and used for microarray analysis. Over 40 EST-derived SSRs have been developed. 4. Total 278 SSRs have been developed from about 5,000 sequences from SSR enriched genomic libraries, and deposited into GenBank (accession number AY526357 to AY526456, and AY731521 to AY731698). 5. Total 22,944 EST clones have been attempted for sequencing and 20,048 quality ESTs have been achieved from 6 cDNA libraries of Tifrunner and GT-C20 with 4,100 and 2,700 unigenes, respectively. The preliminary data show that there are over 600 SSRs and SNPs.