Cocoyam root rot disease caused by Pythium myriotylum in Nigeria

In Nigeria, cocoyam (Xanthosoma sagittifolium) is an important staple which besides being a food crop, serves as a major source of income for rural households. Yield losses due to cocoyam root rot disease (CRRD) remains a major constraint to increased cocoyam production in Nigeria. Until now, this disease has been attributed to a pathogen complex including Fusarium solani and Rhizoctonia solani. However, symptoms observed in infected fields in Nigeria are similar to those caused by the oomycete, Pythium myriotylum, on diseased cocoyam plants in Cameroon and Costa Rica (Pacumbamba et al. 1992; Perneel et al. 2006). Thus, the aim of this study was to determine the primary causal pathogen of CRRD disease in Nigeria.