Population build-up and damage of Scutellonema bradys and Meloidogyne spp. on local yam cultivars under field and storage conditions in Benin

Plant-parasitic nematodes are some of the most damaging pests in yam production and storage in West Africa. Four local yam cultivars (cv. Aïmon, Baniouré Kpika, Klatchi and Môrôkô) were assesed for their resistance to plant-parasitic nematodes in both fields and storage. Nematode population densities and damage and tuber yields were collected during the field study while nematode populations densities and damage and tuber weight losses were assessed over five month storage period. At harvest, Meloidogyne spp. and S. bradys population densities were significantly lower in tubers of cv. Klatchi, Môrôkô and Baniouré Kpika than that of cv. Aïmon. Average tuber yields varied between 1325 g/m² (cv. Baniouré Kpika) and 1678 g/m² (cv. Môrôkô). During storage, Meloidogyne spp. population densities in tubers were reduced by up to 90% after 3-month storage period and 100% after 5-month storage period. In contrast, a high build-up of S. bradys populations was observed in tubers over a 5-month storage period with reproductive factors varying from 4.22 (cv. Aïmon) to 14.04 (cv. Klatchi). Tubers weight losses varied from 51.64% (cv. Môrôkô) to 58.23% (cv. Klatchi) over 5-month storage period. This study pointed out the need for developing integrated nematode management technology to provide quality yam tubers to consumers. Key words : Dioscorea spp., nematode management., post-harvest loss, plant-parasitic nematodes, West Africa