Crop Biotech Update

Potato with Dual Resistance to Fungal Diseases

March 5, 2010

Scientists at the U.S. Department of Agriculture Agricultural Research Service in Washington State University have identified sources of resistance to powdery scab and black dot. The diseases caused by Spongospora subterranean and Colletotrichum coccodes, respectively, attack potato plant's tubers or stems which may lead to yield losses of up to 25 percent and prevent the normal growth of the tubers.

Screening for resistance to these fungal diseases which started in 2004 yielded five advanced potato breeding lines that have been developed from wild species Solanum hougasii, and the commercial release of Summit Russet. The lines consistently showed fewer disease symptoms characterized by decreased root galling for powdery scab, and decreased incidence of sclerotia-infected stems for black dot. The lines will be made available for development of commercial varieties with dual resistance to the fungal diseases.

Details of the story can be seen at http://www.ars.usda.gov/is/pr/2010/100302.htm