Genes that Govern Toxin Production in Gray Mold Found

The fungus Botrytis cinerea, also known as the gray mold, is regarded as one of gardeners’ worst enemies because of the damage it can cause to a range of plants. It is the causal agent of the destructive gray mold disease that affects more than 200 ornamental and agriculturally important plant species, including potatoes, tomatoes and pepper. Gray mold secretes potent phytotoxins such as botrydial and botcinic acid. The only way to eliminate the pathogen is to spray plants with fungicides, which can be costly and can cause harm to human health and the environment. Scientists at the Brown University in the U.S., University de Cadiz in Spain and the French National Institute for Agricultural Research have figured out how the fungus’s deadly toxin is made and how it might be disarmed naturally.

Led by Muriel Viaud and David Cane, the researchers identified a cluster of five genes that is responsible for production of botrydial, the toxin the mold uses to kill and invade plant cells. Introduction of a mutant gene that suppresses the function of sesquiterpene cyclase, the mastermind enzyme for botrydial production, resulted to molds that cannot produce the toxin. The discovery will allow scientists to devise ways to control the mold without using fungicides.

For more information, read http://news.brown.edu/pressreleases/2008/12/mold The paper published by ACS Chemical Biology is available at http://pubs.acs.org/doi/full/10.1021/cb800225v