The most economically important plant-parasitic nematodes affecting sweetpotato are Meloidogyne spp., (Courtesy of John Eisenback 1945) top left, Pratylenchus spp., (Courtesy of V Vanstone) top middle, and Rotylenchulus reniformis (Courtesy of Kathy Lawrence) top right. Sweetpotato tuber shows symptoms of root galling (middle left) due to Meloidogyne spp. with internal dark spot damage (middle right) where the mature female nematodes are found inside the tuber (bottom left) and the associated nematode eggs (bottom right) (Courtesy of Kathy Lawrence and Claire Schloemer).