Submitted to: Soybean Research World Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 8/5/1999
Publication Date: N/A
Technical Abstract: Accessions of perennial Glycine species were evaluated for resistance to Sclerotinia sclerotiorum, the fungus that causes Sclerotinia stem rot (SSR) and Fusarium solani f. sp. glycines the fungus that causes sudden death syndrome (SDS). Control of these diseases by host resistance is one management tool to reduce yield losses. Most commercial soybean varieties are highly susceptible to both of the pathogens that cause SSR and SDS. In the initial evaluation of 787 perennial Glycine accessions screened for resistance to the pathogen causing SSR, 183 accessions had plants with greater than 75% survival. The highest percentage of accessions that had plant survival frequencies over 75% was G. tabacina (144 out of 232 accessions screened). Other species that had some accessions that had plant survival frequencies over 75% included accessions of G. latifolia (16 out of 42 accessions screened) and G. microphylla (eight out of 31 accessions screened). Sources of resistance to S. sclerotiorum did not occur in G. arenaria, G. argyrea, G. curvata, G. cyrtoloba, G. latrobeana, or G. pindanica. In the initial evaluation of 767 accessions screened for resistance to the pathogen causing SDS, 116 had disease severity ratings less than 2 on a 1 to 5 disease severity scale where 1 is most resistant. At least a few accessions in G. argyrea, G. canescens, G. clandestina, G. curvata, G. cyrtoloba, G. falcata, G. latifolia, G. tabicina, and G. tomentella had disease severity ratings less than 2. Sources of resistance were not found in G. arenaria, G. latrobeana and G. pindanica. These 16 perennial Glycine species represent untapped resources for improving traits in soybean including disease resistance.