Researchers at North Carolina State University have identified candidate
genes and cellular processes believed to control hypersensitive defense
response (HR) in
<[www.isaaa.org]
load/02%20Maize%202013.pdf> corn. Hypersensitive defense is a response by
corn plants when they are under pathogen attack, where they sometimes
respond by killing their own cells near the site of the attack to thwart
further damage from the attacker. This cell sacrifice can cause very small,
often microscopic, spots or lesions on the plant.

The NC State researchers worked with their colleagues from Purdue University
and examined more than 3,300 corn plants that had exaggerated HR because one
particular resistance
[www.isaaa.org] gene,
Rp1-D21, won't turn off. They examined the entire corn gene blueprint to
find the genes most closely associated with HR. They found 44 candidate
genes that seem to be involved in defense response, programmed cell death,
cell wall modification and a few other responses linked to resisting attack,
says Dr. Peter Balint-Kurti, a U.S. Department of Agriculture (USDA)
professor who works in NC State's plant pathology and crop science
departments.

"It's similar to a human having an auto-immune response that never stops,"
Balint-Kurti says. "This mutation causes a corn plant to inappropriately
trigger this hypersensitive defense response, causing spots on the corn
plant as well as stunted growth."


<[news.ncsu.edu]
nse-response/> [news.ncsu.edu]