Field tests have shown that a new system of planting different varieties of rice plants can dramatically reduce problems with the most important fungal disease of rice, with implications for greater rice production around the world and more food for literally billions of people. Studies done in Yunnan Province of China, the results of which were just published in the journal Nature, show that losses to the fungal disease "blast" can be almost eliminated in some of the types of glutinous rice in which it was the most severe problem, at times destroying entire crops.

"This approach was really a phenomenal success, much more effective than anyone predicted," said Chris Mundt, a professor of botany and plant pathology at Oregon State University and co-author on the study. "This is not a new concept, but it's a sound application of ecological principles to crop agriculture and it was astounding to see the scope of disease reductions that were a result." It may also be possible to dramatically reduce the use of chemicals on a sustainable basis and significantly increase the income rice farmers are able to earn from the same area of land, researchers say.

Rice is a primary food and leading source of caloric intake for more than half of the world's population, and is clearly the most important single food crop on Earth.

But rice production has historically struggled with blast, a fungus that causes lesions on rice plants, reduces yields and in severe cases can kill the entire plant. Total crop losses are possible, especially when the crop year is unusually cool and wet, and a 20 percent loss in rice yield is routine, Mundt said.

Blast can affect either the glutinous, or more "sticky" varieties of rice, experts say, and the non-glutinous varieties that are the types most commonly sold in groceries around the world. Different varieties have been developed in attempts to find some that showed more natural resistance, but the fungus often overcam
'"/>

Contact: Chris Mundt
mundtc@bcc.orst.edu
541-737-5256
Oregon State University
15-Aug-2000