Crop Biotech Update

Corn Gene Helps Fight Multiple Leaf Diseases

February 3, 2012

Scientists at the U.S. Department of Agriculture (USDA) and partners discovered a single gene that could confer resistance to three important diseases namely, southern corn leaf blight, northern leaf blight, and gray leaf spot. These diseases have been problems of corn producers globally because of its common symptom of forming lesions on leaves.

Plant geneticist Peter Balint-Kurti and colleagues examined 300 corn varieties from different parts of the world and found no variety that exhibit complete resistance to the three diseases. However, they observed that each variety has different severity of symptoms for the diseases.

The team conducted a statistical analysis called association mapping to search for parts of the genome that could be linked with variation in disease resistance. They observed that some resistance genes conferred resistance to two or more different diseases. They also found a gene that seemed to confer multiple disease resistance. This gene is called glutathione S-tranferase (GST), which is a member of a family of genes known for their functions in regulating oxidative stress and in detoxifications.

Read the media release at http://www.ars.usda.gov/is/pr/2012/120201.htm. Their study was also published in the Proceedings of the National Academy of Sciences (PNAS): http://www.pnas.org/gca?allch=&submit=Go&gca=pnas;108/18/7339.