DIFFERENTIAL RESPONSES OF VIGNA UNGUICULATA CULTIVARS TO ROOT KNOT NEMATODES (MELOIDOGYNE SPP.)

Abstract

The root-knot nematodes are the most important phytonematodes in the world, as they infect cultivated plants and adapt more to different types of environments, what contributes to their greater dispersion. In Brazil, there are more than 20 species, notably M. incognita, M. javanica, M. arenaria, M. hapla, M. enterolobii, and M. konaensis. Such phytoparasites affect crops differently, including cowpea [Vigna unguiculata (L.) Walp.], a well-adapted species of the Northeast semiarid. The objective of this work was to verify the hospedability of the cowpea cultivars Pitiúba, Sempre Verde, João Paulo II, and Setentão to M. incognita, M. arenaria, M. enterolobii, and M. konaensis. It was observed that the Pitiúba cultivar was the only one susceptible to M. enterolobii, whereas João Paulo II presented resistance only to this species. João Paulo II and, Setentão cultivars were susceptible to M. konaensis. Sempre Verde showed resistance to M. incognita, M. arenaria, M. enterolobii and M. konaensis, suggesting that this cultivar, which is among the cultivars recommended for the Brazilian Northeast region, would be less affected in field conditions infested with this species of root-knot nematodes.