Plant & Animal Genomes XIII Conference

January 15-19, 2005
Town & Country Convention Center
San Diego, CA

Proteomic And Genomic Approaches To Molecular Breeding Of Resistance To Soybean Sudden Death Syndrome And Cyst Nematode In Elite Cultivars

Jawad Afzal , R Ahsan , Samreen Kazi , Chet Langin , MJ Iqbal , DA Lightfoot

  Genomics Core Facility, Southern. Illinois University, Carbondale, IL62901.USA. ga4082@siu,edu

Understanding of how the soybean resists two of its major pathogens is being developed in parallel with tools useful to plant breeders. Markers for resistance are used for millions of selections annually. Methods for high-through-put selection in soybean for 5 genes for resistance to SCN and seven for resistance to SDS were previously developed . We have developed markers from allele sequences following positional cloning of Rhg1, Rhg4 (for resistance to soybean cyst nematode) and Rfs2 (for resistance to Fusarium solani f.sp. glycines causal agent of sudden death syndrome). Antibodies have been prepared and shown to be specific. RHG proteins form temperature sensitive hetero- and homo-dimers. Binding domains are defined by CD and deletion series. Elicitor/ substrates are being analysed by MS. Combining protemics with genome sequencing and substitution maps will annotate and isolate the 300-400 economically important soybean genes efficiently within the next decade. Marker assisted selection efficiency will be increased and the yield of new cultivars improved faster that ever before. This work was supported by NSF project #9872635, the ISPOB and the USB.