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Soybean Plant Health

Agronomic Impact of Soybean Rust

Asian Soybean Rust

Asian soybean rust is an aggressive foliar disease that destroys photosynthetic tissue, causing premature defoliation, early maturation, and lower yields. Rust infection affects pod filling, the number of seeds and seed weight.

Yield loss
Soybeans are susceptible to rust infection at all growth stages, but the amount of yield loss will depend on the crop stage when infection occurs. The most susceptible crop stages are between early flower stage (R1) and mid-seed development stages (R5). The environmental conditions, amount of spores produced during the growing season, the soybean variety planted, and whether control tactics were appropriate and correctly implemented during the growing season will also determine yield loss. Yield loss in other countries has ranged from 10-90%. However, it is difficult to predict yield loss potential in Wisconsin.

The occurrence of soybean rust is the highest in regions of China below 34° latitude. This is much further south than Wisconsin. High amounts of rainfall also has been an important factor in epidemics in China. Although many factors may render this comparison invalid, this information is the best available to make predictions on soybean rust activity in Wisconsin.

The USDA Risk Management Agency (RMA) has stated that unavoidable loss of production due to  soybean rust disease is a covered peril under the Coarse Grains Crop Provisions...read the full statement here»

Information from this site can be copied and distributed for educational use. Please credit the source with our name and URL: University of Wisconsin-Madison, Departments of Agronomy, Entomology, and Plant Pathology at  www.plantpath.wisc.edu/soyhealth.