ECOLOGY AND PATHOGENICITY OF 4 TRICHODORID SPECIES FROM THE SEMIARID REGION OF WEST-AFRICA

Laboratory studies showed that trichodorids from the semi-arid region of West Africa need relatively low soil temperature levels for reprodu ction. The nematodes are not able to enter anhydrobiosis. Their locali zation at depth is probably a response to desiccation of the soil duri ng the dry season and to high soil temperatures in the upper layers of the soil during the rainy season. Laboratory experiments showed that P. minor is pathogenic to sorghum, cowpea and eggplant, P. nanus to mi llet and sorghum, and P. rhodesiensis to peanut and sorghum. In each c ase the weight of shoots and roots was reduced by the nematodes but ot herwise there were no obvious disease symptoms.