Major Pests & Damage
Early Blight
(Alternaria solani)
Early Blight cause dark, sunken lesions at or above the soil line, sometimes called collar rot.
Late Blight
(Phytophthora infestans)
Late Blight cause black and brown lesions appear on stem and petioles; when petioles or leaf stalks are affected, entire leaf can collapse; entire vine or plant can quickly collapse and die in period of high humidity.
Potato Scab
(Streptomyces scabies)
Scab symptoms are usually first noticed late in the growing season or at harvest. Tubers are susceptible to infection as soon as they are formed. Lesions start out as small brownish spots, which enlarge into water-soaked circular lesions within a few weeks of infection.
Black Scurf
(Rhizoctonia solani)
Solani causes black scurf on tubers and stem and stolon canker on underground stems and stolons and it occurs wherever potatoes are grown. Poor stands, stunted plants, reduced tuber number and size, and misshapen tubers are symptoms of R. solani infection.
Root Knot Nematodes
(Meloidogyne spp)
Nematode injury varies among species, but can include galls on roots and tubers (root-knot), necrosis of roots (root-lesion), or a subtle stubby-appearance (stubby-root). Above ground plant symptoms may range from no apparent injury to less vigorous growth to stunting, yellowing, wilting, and death.
