CONTROL OF Meloidogyne incognita AND Rotylenchulus reniformis AND ITS EFFECT ON THE YIELD OF SWEET POTATO AND CASSAVA

Abstract

Pre-plant treatment of different nematicides, in pot experiments, using the manufacturers' recommended rates had variable effects on the growth of sweet potato and cassava and on the population of Meloidogyne incognita and Rotylenchulus reniformis 4 months after application. Low gall and egg mass ratings were obtained in chemical-treated plants, except those treated with Hostathion 5G. In all cases, the application of Nemagon 75 E.C. and Temik 15G increased the root, tuber and top weights of sweet potato and cassava and gave from 65-85% reduction in nematode population compared to Furadan 5G and Bunema 40 E.C. which gave from 45-70% reduction. Hostathion 5G was the least effective among the chemicals tested. The application of chicken manure significantly increased roots, tubers and tops of sweet potato and cassava compared to those obtained with nematicides. However, there was no apparent correlation between growth response and per cent control.