Duane Dailey Senior Writer 573-882-9181 DaileyD@missouri.edu June 6, 2005 MU soybean breeder returns from Vietnam optimistic; Missouri varieties are growing in rust-infected plots COLUMBIA, Mo. - David Sleper came back from Vietnam optimistic after seeing his best Missouri soybean varieties growing alongside soybeans infected with Asian soybean rust. University of Missouri plant breeders, including Sleper, have sent 100 top soybean varieties to be tested by Vietnamese researchers in plots near Hanoi. "I think we will find rust tolerance in some of our existing Missouri varieties," Sleper said. "We'll know a lot more in a few weeks when we get the first data back." In the Vietnamese climate, the Missouri soybeans were flowering, a stage when the plants become most susceptible to infection by Asian rust. Sleper saw signs of infection on susceptible Vietnamese varieties. Just a few Missouri varieties showed infection. "I'm trying not to be too optimistic too soon," Sleper said. "Our soybeans may become infected and die. "The rust season (in Vietnam) is just beginning. They have a moist, humid climate that is favorable for Asian soybean rust." It will be critical for Missouri farmers to know which local varieties are naturally resistant or tolerant to Asian soybean rust should rust become prevalent in this state. A strain of the rust, believed to have blown in from South America, was discovered on plants in the Missouri Bootheel in fall 2004. MU agronomists are watching the 2005 crop for signs of rust. Resistant varieties would reduce the need for spraying fungicides to control the rust. "The Vietnamese are testing our varieties in two locations," Sleper said. "One test is in open fields with other Vietnamese varieties. The second test is in a net house with Missouri soybeans and alternating rows of rust-susceptible Vietnamese varieties." The U.S. breeders want maximum exposure to rust spores. The agreement to test Missouri beans in the Asian rust environment was arranged by Henry Nguyen, director of the National Soybean Biotechnology Center located at MU. He is working in cooperation with the Vietnam Ministry of Agriculture and Rural Development, Vietnam Agricultural Science Institute and Cantho University. Other MU researchers accompanying Nguyen and Sleper on their late-May trip were Gary Stacey, Columbia, and Grover Shannon, Portageville, Mo. They were accompanied by Tara VanToai, USDA Agricultural Research Service, and Tom Clemente, University of Nebraska. The group gave lectures to Vietnamese students and faculty on soybean biotechnology. The Vietnam Education Foundation, an agency funded the U.S. Congress to encourage cooperation between universities in the two countries, sponsored the teaching exchange. While in Vietnam, the Missourians also worked out an agreement for Vietnamese soybean breeders to crossbreed their rust-resistant varieties with Missouri varieties. "We need their (resistance) genetics inserted into our soybean lines," Sleper said. Missouri breeders are creating varieties with cyst nematode resistance, food beans and soybeans with special oil traits. All those would benefit from rust resistance if the disease becomes a common problem in Missouri. Source: David Sleper (573) 882-7320; Henry Nguyen (573) 883-5494 Return to Current News Releases College of Agriculture Food and Natural Resources AgEBB