Solanum sarrachoides (Sendtner)
Significance: Potato late blight, which is caused by Phytophthora infestans, costs growers throughout the world more than $3 billion in fungicides and other control measures. Extension agents in northern Maine discovered hairy nightshade (Solanum sarrachoides) plants speckled with dark and oily spots on the foliage. Scientists in the USDA’s Agriculture Research Service (ARS) analyzed the plants and verified that the hairy nightshade is an alternate host of P. infestans. A limited survey found that over half of the fields in Maine contain hairy nightshade. Growers should be encouraged to incorporate control of hairy nightshade into their late blight management program.
Peabody, E. 2006. Weed implicated in Potato Blight Persistence. USDA-ARS News. 12 December 2006. Available online: http://www.ars.usda.gov/is/pr/2006/061212.htm