Pathogenicity and reproduction of Meloidogyne incognita (Kofoid and White) chitwood on African yam bean, Sphenostylis stenocarpa (Hochst Ex. A. Rich) Harms accessions

Abstract

Studies were carried out to determine the host status of 12 African yam bean (Sphenostylis stenocarpa) accessions to Meloidogyne incognita infection. The experiments were laid out in a completely randomized design (CRD) with six replications. Inoculated plants received 4,000 eggs of M. incognita, while those without eggs served as controls. Data were collected on growth, yield and yield parameters of the African yam bean accessions. Data collected were subjected to statistical analyses using Genstat for windows, version 3.2. Results showed that growth, yield and yield parameters were significantly (P≤0.05) reduced in inoculated accessions when compared with the controls. Four accessions, TSS 63, Eha-Amufu, TSS 56 and Ugbokolo, were tolerant to M. incognita infection, while the rest of the accessions, TSS 3, TSS 4, TSS 22, TSS 5, TSS 10, TSS 11, TSS 112 and TSS 7, were susceptible to M. incognita infection. Percentage yield reduction as a result of M. incognita infection ranged from 0.21 to 74.3%. It was observed that none of the accessions was resistant to M. incognita infection. The tolerant accessions are therefore recommended for use by African yam bean farmers as they would check yield losses caused by M. incognita.

Key words: African yam bean, Meloidogyne incognita, pathogenicity, Sphenostylis stenocarpa.