Published 18 Sep 2008
Update on soybean rust
Kiersten Wise and Greg Shaner
Botany & Plant Pathology Dept., Purdue Univ.
West Lafayette, IN 47907
Email address: kawise
he recent hurricane activity in the Gulf has increased soybean rust spread in the southern U.S. There is now concern that rains from hurricanes may have transported spores into the Midwest. Whether soybean rust will develop in Indiana over the next few weeks depends on whether viable soybean rust spores were deposited in the area from Hurricanes Gustav and Ike , and if conditions in Indiana remain favorable for spore germination and infection (high humidity and rainy weather).
Soybean rust is economically damaging to soybeans in growth stages R1 to R5. Once the plant is at R6, there is usually no need to manage soybean rust. Currently in Indiana, most of our soybean acreage is at R6 or later, and to these growers soybean rust is a non-issue for 2008. There is limited acreage of double-cropped soybean in the southern part of the state that is still at R4 to R5, and growers may need to deal with rust in these fields.
We are continuing to monitor sentinel plots and late-planted commercial
fields in the state for soybean rust and will post updates on our findings
throughout the remainder of the growing season. If you suspect a soybean field
is infected with rust, please contact Kiersten Wise at (765) 496-2170. For
the most recent information, please call the Purdue Soybean Rust Extension
Hotline at 1-866-458-RUST (7878) or go to the USDA Soybean Rust website at