Submitted to: Molecular Genetics of Plant-Microbe Interactions Symposium Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 7/14/1996
Publication Date: N/A
Technical Abstract: Fungal pathogens account for the greatest overall losses associated with plant disease. This year in the United States, high priority has been given to control of two emerging fungal epidemics, late blight on potato caused by the Oomycete Phytophthora infestans, and Karnal bunt of wheat caused by the Basidiomycete Telletia indica. In 1994, a major epidemic of late blight occurred in Wisconsin and in states along the Eastern coast of the U.S. Most of the potato crop in Northern Maine was lost in 1995, cool wet weather in Idaho led to the incidence of late blight on potato for the first time in history. This year, cool wet weather is again favoring late blight in many potato growing areas of the United States. Control of this disease is becoming increasingly difficult due to the emergence of fungal isolates with resistance to the fungicide ridomyl and the recent migration of the highly virulent A2 mating type into the United States. Last year late blight on potato also led to loss of 30% of the potato crop in China where it is an important food staple thus threatening China's food supply. The discovery of Karnal bunt on wheat in the U.S. for the first time this year may severely affect seed quality and will limit the exportation of wheat from the United States through quarantine. Clearly timely research is needed in order to design new and improved strategies to control these and other fungal diseases worldwide.