Wednesday, November 15, 2006

Identification of New Genes for Resistance to Soybean Mosaic Virus in Soybean.

Cuiming Zheng1, Pengyin Chen2, Ainong Shi3, and Rose Gergerich1. (1) University of Arkansas, 1175 W Leroy Pond Dr. #273, Fayetteville, AR 72701, (2) 115 Plant Science Bldg, University of Arkansas, University of Arkansas, Dept of CSES, Fayetteville, AR 72701, (3) Department of Crop, Soil, and Environmental Sciences, University of Arkansas, Fayetteville, AR 72701

Soybean mosaic virus (SMV) causes one of the most destructive viral diseases in soybean worldwide. Ninety-eight SMV isolates identified in the U.S. were classified into seven strain groups (G1 to G7). Three independent loci (Rsv1, Rsv3, and Rsv4) have been identified for SMV resistance. In an initial study, 209 soybean genotypes were inoculated with G1 or G7, results showed that 129 genotypes were resistant to one or two strains. The objective of this research was to screen the 129 resistant soybean genotypes with G2 through G6 to differentiate specific alleles of SMV resistance loci in these genotypes. The results indicated the existence of new alleles for SMV resistance gene.  Soybean genotypes Corsica, Yuwoltae, PI 398289, PI 407975B, Clifford, and PI 398833 carry new alleles at Rsv1 locus based on the comparison of their differential reaction pattern against published eight Rsv1-alleles.  Bryan and CNS carry new alleles at Rsv3 locus.  PI 61947, PI 398479, Suzuyutaka, Beeson, and Virginia likely carry Rsv1-h, Rsv1-r, Rsv1-s or new alleles at Rsv4.  Research is ongoing to confirm the new SMV resistance alleles via genetic study.