RIVERSIDE, Calif.-Late blight, caused by a fungus-like microbe, is a plant disease that mainly attacks potatoes and tomatoes, is difficult and economically challenging to eradicate, and was largely responsible for the Irish potato famine of the mid-19th century. Given that world potato production is about 320 million tons per year (20 million tons per year in the United States), late blight is a major problem worldwide even today. With total costs of the disease estimated at more than $7 billion per year, it can drive growers out of business and increase food prices.
Howard Judelson, a professor of plant pathology at the University of California, Riverside, has received a $9 million five-year grant from the USDA National Institute of Food and Agriculture to research late blight and ensure a sustainable and long-term control of this devastating disease.
Cathie Woteki, USDA under secretary for research, education and economics, visited UC Riverside March 30 to make a formal announcement of the research grant and meet with Judelson as well as other campus scientists and administrators.
Late blight symptoms include the appearance of dark lesions on leaf tips and plant stems. In humid conditions, white mold appears under the leaves. Infected potatoes show gray or dark patches outside; inside, such potatoes show reddish brown lesions. A threat to home gardeners and commercial farmers, the disease can wipe out tomato and potato fields within a week.
The disease is caused by Phytophthora infestans, the most significant pathogen of potato and a noteworthy tomato pest. Spores of the pathogen primarily travel in air, eventually landing on plants where the spores colonize leaves and cause them to die. Spores also can enter the soil, reach potato tubers and destroy them. Available fungicides tend to be expensive and have potentially adverse environmental effects. Moreover, some strains of the pathogen are resistant to some fungicides.
The research project will emphasize providing growers with better tools for managing the disease. These include better systems for making disease management decisions, plant varieties that are more resistant, tools for rapid identification of the pathogen and tools for characterizing pathogen strains. The researchers also will test and expand the use of social media and smartphone technology to communicate with growers.
In the United States, late blight is seen predominantly on potato in eastern states like Maine, New York and Pennsylvania, and outbreaks also occur in the Midwest and West. Tomato production from Florida up the East Coast is also vulnerable to the disease. In California, late blight is mostly seen in the central valley in the early season, when conditions are moist and cool.
Judelson will be joined at UC Riverside by Thomas Girke, an associate professor of bioinformatics, who will help sequence strains of Phytophthora infestans, and scientists at Cornell University, N.Y.; USDA-Agricultural Research Service, Corvallis, Ore.; the University of Idaho; the Scottish Crop Research Institute; North Carolina State University; the University of Florida; the University of Kentucky; La Universidad Autónoma Chapingo, Mexico; Boyce Thompson Institute, N.Y.; the University of Maine; Oregon State University; Pennsylvania State University; the University of Wisconsin; the University of Maryland; the University of South Carolina; and Purdue University, Ind.
The grant, which became effective March 1, has a strong undergraduate research component. Of the $9 million total award, $4.3 million is budgeted to UC Riverside for research and education activities; the rest will be shared by the other 16 institutions.
The University of California, Riverside is a doctoral research university, a living laboratory for groundbreaking exploration of issues critical to Inland Southern California, the state and communities around the world. Reflecting California's diverse culture, UC Riverside's enrollment has exceeded 20,500 students. The campus will open a medical school in 2012 and has reached the heart of the Coachella Valley by way of the UCR Palm Desert Graduate Center. The campus has an annual statewide economic impact of more than $1 billion.