Prevalence of plant-parasitic nematodes in rice fields in Ghana
Rice (Oryza sativa L.) is one of the most cultivated crops worldwide whose production in sub-Saharan Africa is extensively affected by root nematodes. The objective of this study was to identify and establish the distribution of plant-parasitic nematodes (PPNs), in rice growing fields within different regions of Ghana. Soil and root samples were taken from rice fields, namely fourteen from Volta Region, eleven from the Soil and Irrigation Research Centre (SIREC), Kpong (Eastern Region); and five from Dawhenya (Greater Accra Region). The soil samples were taken from 0-30 cm depths, together with root samples. A total of twenty-four nematode genera were identified in soil and root samples from the three regions. These included: Aphelenchus spp., Belonolaimus spp., Ditylenchus spp., Dolichodorus spp., Helicotylenchus spp., Hemicriconemoides spp. Hemicycliophora spp. Heterodera spp., Hirschmaniella spp., Hoplolaimus spp., Longidorus spp., Meloidogyne spp., Paralongidorous spp., Paratylenchus spp., Pratylenchus spp., Radopholus spp., Rhabditida spp., Rotylenchulus spp., Scutellonema spp., Trichodorus spp., Tylenchornchus spp., Tylenchulus spp., Tylenchus spp. and Xiphinema spp. In the Volta Region, Tylenchus spp. was the most abundant (29.01%) in the soil; while Meloidogyne spp. was most the abundant (36.86%) in the roots. In Dawhenya regions, Meloidogyne spp. was the most abundant (26.96%) in the soil; while Tylenchus spp. was the most abundant (25.94%) in the roots. In the Eastern Region, Meloidogyne spp. was the most abundant (41.7%) in the soil; while Pratylenchus spp. was the most abundant (36.1%) in the roots. These nematodes threaten rice production in Ghana, if not managed well in farmer’s fields.