EVALUATION OF COWPEA (VIGNA UNGUICULATA L.) GERMPLASM FOR THE SOURCE OF RESISTANCE TO ROOT-KNOT NEMATODE, MELOIDOGYNE INCOGNITA

Abstract

Screening experiments were conducted during 2013 to 2015 to assess the host status of 350 accessions of cowpea (Vigna unguiculata) for resistance to Meloidogyne incognita. Based on the number of root galls induced by M. incognita among the tested accessions, six (EC0517140, EC0528391, EC0723686, EC0724523, EC0725122, and IC0253277) were resistant, and the rest were susceptible. The resistant accessions reduced root gall formation by 96-99% as compared to highly susceptible accession EC0724571. Nematode penetrations were also lower in roots of all resistant cowpea accessions compared to the susceptible accession EC0724571 (P<0.05). Similarly, egg-mass formation was retarded in the resistant accessions when observed 45 d after inoculation (P<0.05). These resistant accessions may be useful in plant breeding programs to develop nematode resistant cowpea cultivars