Pathogenic effect of root-knot nematode, Meloidogyne incognita on african white yam, Dioscorea rotundata

An initial inoculum level of 100 juveniles of Meloidogyne incognita per plant caused significant reduction in fresh and dry fibrous root weight and tuber yield and proved to be pathogenic to Dioscorea rotundata. Severe well pronounced large sized galls wcre noticed in plants which received an initial inoculum of 100 J/₂ plant or more. The multiplication rate of the nematode was maximum at the lowest level of inoculum (10J₂) and minimum at the highest level (10000J₂).