Submitted to: International Congress of Plant Pathologists
Publication Type: Abstract Only
Publication Acceptance Date: September 5, 2007
Publication Date: August 24, 2008
Citation: Li, S. 2008. Identification of New Potential Sources of Resistance to Soybean Rust. International Congress of Plant Pathologists. 90:S2.64 Technical Abstract: Asian soybean rust (ASR), caused by Phakopsora pachyrhizi Sydow, is one of the most destructive diseases of soybean (Glycine max (L.) Merr.). Before 2004, ASR was not present in the continental USA and evaluation of U.S. soybean lines for resistance was done only with foreign isolates. Now that ASR has been discovered in North America, evaluation of soybean lines using US isolates is important in order to identify new resistance sources. In this study, 10 plant introductions (PI) previously identified as resistant line in Paraguay were evaluated using an ASR isolate from Mississippi. Replicated experiments were conducted in a growth chamber at the USDA–APHIS PPQ approved Stoneville Research Quarantine Facility from 2006 to 2007. Results from the seedling assays indicated that most of those PIs had lower ASR severity and less sporulation than the susceptible check cv.Williams 82. Although none of the PIs had an immune reaction, PI567102B was identified as the most resistant line having the lowest severity, no sporulation, and the red-brown reaction. Further evaluation using other U.S. isolates is in progress. PIs that have resistant reactions to both U.S. and Paraguay isolates may be important sources of resistance to soybean rust.