Augustus Missah and Jeffrey C. Peters
Ghana is an important yam-producing country, but information on the incidence of plant parasitic nematodes capable of reducing the yield and quality of yams is limited. Samples of soil, roots of intercrops and tubers of yam were collected from 50 farms in 26 villages in 17 administrative districts of Ghana during mid-season in July 1997, and processed in the laboratory for plant parasitic nematodes of importance to yam. Results indicated the presence of Scutellonema bradys; Pratylenchus spp; Meloidogyne spp; Helicotylenchus spp and Rotylenchulus reniformis in various populations in the soil and roots of intercrops. Apart from R. reniformis, all other nematode species were found in over 55% of soils planted to yam. Pratylenchus was the commonest genus infesting roots of intercrops. S. bradys was the most important nematode associated with yam, being found in 35.6% of tubers from 58.6% of farms. Mean population of S. bradys per 5 g yam tuber peels was 411, compared with 22 and 8 of Pratylenchus and Meloidogyne, respectively.