Disease-causing Mechanism of Cochliobolus victoriae Fungus in Plants

A research study from Oregon State University gave scientists an idea why some grains are susceptible to a yield-reducing fungus Cochliobolus victoriae. Studying the fungus' mechanism in the model plant Arabidopsis thaliana (thale cress), scientists discovered that victorin, a toxin produced by the fungus, attacks thale cress by binding to a protein called TRX-h5. This protein, however, has a guard watching over it called LOV1. When something tries to mess with the protein, the guard causes the cells to "commit suicide" in defense. Believed to share a similar gene with thale cress, the researchers suspect that a similar process occurs in oats, barley, rice, beans and Brachypodium grasses.

The fungus Cochliobolus victoriae causes a disease called Victoria blight, which in the 1940s severely reduced U.S. yields of oats that were descended from a variety named Victoria. The fungus damages leaves and kills seedlings which causes seeds to ripen prematurely, and weakens stems so that the plant falls over. The finding could eventually help plant breeders develop varieties of grains and beans that resist certain diseases.

View OSU's press release at http://oregonstate.edu/ua/ncs/archives/2012/oct/osu-demystifies-how-oat-fungus-kills-plants.