UC Riverside scientists have found a genetic trigger for Ireland’s Great Potato Famine, which caused 1 million Irish to die of starvation. The trigger is found in the Phytophthora microbes, which shut down a defense these plants use to repel infections. Called RNA silencing, the process uses fragments of RNA called “small RNAs” to suppress the activity of certain genes.
Proteins made by Phytophthora called “effectors” block RNA silencing in these plants, reducing their immunity to infection, according to a new study. Researchers led by Wenbo Ma, a UCR associate professor of plant pathology and microbiology published the study in Nature Genetics.
Although there is more control of Phytopthora since the days of the Irish famine, the disease remains a serious risk to agriculture, causing around $6 billion damage to the potato industry worldwide every year.
Ma and colleagues are already studying how to thwart the effectors, which could lead to development of Phytopthera-resistant crops. “We are in the process of testing some plants to manipulate the RNA silencing pathway, and then infect them with Phytopthera pathogens to see whether there’s enhanced resistance or enhanced susceptibility,” Ma said. They are working with Arabidopsis, the plant equivalent of lab rats. If the work is successful, the technology can be used to produce crop plants resistant to the various species of Phytopthora, Ma said.
Ma was joined in the study by UC Riverside’s Yongli Qiao, Lin Liu, Cristina Flores, James Wong, Jinxia Shi, Xianbing Wang, Xigang Liu, Qijun Xiang, Shushu Jiang, Howard S. Judelson and Xuemei Chen. Others who took part are Fuchun Zhang at Xinjiang University, China; and Qin Xiong and Yuanchao Wang at Nanjing Agricultural University, China.
The research was supported by a National Science Foundation grant to Ma and grants from the U.S. Department of Agriculture (USDA) to Judelson and Chen. The research is part of a larger UCR program to research Phytophthora infestans blight, bolstered by a $9 million USDA grant announced in 2011. Last year, UCR released avocado rootstocks that can help control Phytophthora root rot.
Source: FreshPlaza – Irelands Potato Blight Trigger Uncovered
