Submitted to: Crop Science
Publication Type: Peer reviewed journal
Publication Acceptance Date: 12/11/2008
Publication Date: 5/11/2009
Citation: Li, S. 2009. Reaction of Soybean Rust Resistant Lines Identified in Paraguay to Mississippi Isolates of Phakopsora pachyrhizi, the Causal Agent of Soybean Rust. Crop Science. 49(3):887-894 Interpretive Summary: Asian soybean rust (ASR) caused by a fungus (mold) is a new soybean disease in the continental United States. Breeding for resistance to soybean rust is one of the most effective long-term strategies for controlling ASR. In this study, 10 plant introductions (PI) previously identified as resistant in Paraguay were evaluated. Soybean line PI567102B was identified as the most resistant line to ASR. This soybean line can be used as a parent to develop resistant cultivars for United States.
Technical Abstract: Asian soybean rust (ASR) caused by Phakopsora pachyrhizi is one of the most destructive diseases of soybean. Before 2004, ASR was not present in the continental USA and evaluation of U.S. soybean lines for resistance was conducted only with foreign isolates. Since 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 in Paraguay were evaluated using three ASR isolates from Mississippi. Replicated experiments were conducted in a growth chamber at the USDA-ARS Stoneville Research Quarantine Facility. Soybean line PI567102B was identified as the most resistant line. It had the lowest severity, no sporulation, and near immune/hypersensitive to isolate MS07-2, and red-brown reactions to isolates MS06-1 and MS07-1. Soybean lines having resistant reactions to both U.S. and Paraguay isolates may be important source for developing elite cultivars with broad resistance to ASR.