By Grant Mehring, NDCUC Contracted Research Director

A novel corn bacterial disease has come to minor prominence in much of the corn growing belt of the United States. This bacterial disease, for now called simply bacterial leaf streak, is not very well understood, as it is newly discovered, first in Nebraska. As of the most recent update the disease has been discovered in 9 states this year (Colorado, Iowa, Illinois, Kansas, Minnesota, Nebraska, Oklahoma, South Dakota, and Texas), and not in North Dakota. Our closest confirmed field, as communicated by an SDSU research to Dr. Andrew Friskop, our NDSU cereals plant pathologist, is approximately 90 miles SW of Brookings, SD. The closest Minnesota field in unknown at this time, but I will post an update if I find out.

Dr. Friskop and I had a conversation where he relayed some other information to me about this new disease. He said that IF it does show up in North Dakota corn fields, it will be fairly easy to identify as the most common look alike disease would be gray leaf spot. Gray leaf spot is not likely in North Dakota as it requires extreme heat, such as 10 days straight at 90% humidity and combined with high temperatures, as would be seen in parts of Nebraska and other southern states.

University of Nebraska plant pathologist Tamra Jackson-Ziems gave some identification tips for the bacterial leaf streak disease in corn. She noted that the disease produces lesions within leaf veins that are long and narrow with wavy appearing borders, which can be tan, brown, or orange. The disease has been found to show up on lower leaves first.

Much of the common epidemiology about this disease is unknown, so keep an eye out for information about this disease as it becomes available. Like other bacterial diseases such as Goss’s wilt, there are no known chemical treatments at this time. In the next post I will discuss our weather and growing season to date, to see how our corn crop maturity is coming along throughout the state.