One of the world’s worst weeds (Holm) Blackberry nightshade (Solanum americanum & S.nigrum) is a weed of 37 crops in 61 countries. Alternate host for diseases including anthracnose, Cercospora, blight, leaf spot and powdery mildew, at least 13 nematodes, 3 bacterial diseases, 7 fungal diseases including Rhizoctonia and over 30 crop viruses. (more…)