The field crop pathology research program is tracking the distribution of corn and soybean field diseases in Indiana. We are predominantly interested in the following samples (but always keeping an eye out for others):

Corn: tar spot, northern corn leaf blight, and southern corn rust
Soybean: frogeye leaf spot

Recent rains and increased humidity across Indiana have increased the risk for foliar diseases to develop in both corn and soybean. Much of the corn has begun to tassel and soybeans have begun to flower. We are starting to see common diseases in the lower canopy of corn, as we were out scouting this past week. A few diseases that I have seen included gray leaf spot, northern corn leaf blight, common rust, Physoderma brown spot and northern corn leaf spot in corn (Figure 1). Diseases in soybean have been extremely low – I found a few frogeye lesions this past week. Since we are at R1 it is time to scout your soybeans for frogeye leaf spot. Management practices for frogeye are aimed reducing soybean susceptibility and inoculum availability. Infected debris from previous crops is the primary source of inoculum for this disease. Any practice that helps reduced or[Read More…]

Early planted corn in Indiana is reaching late vegetative stages and tasseling in the south. Therefore, it is time to start monitoring for diseases to make an informed decision if a fungicide is necessary. This week we have found a low incidence of tar spot, gray leaf spot, northern corn leaf spot, Anthracnose, and common rust in the lower canopy.