Variability of host damage and response of some cowpea breeding lines to root-knot nematodes, <i>Meloidogyne</i> spp.

Abstract

Field and screen house studies were conducted at the International Institute of Tropical Agriculture (IITA) Research Farms, Minjibir, Kano State and farmer’s plot, Ringim, Jigawa State in Sudan Savannah Agro-ecological Zone, North-Western, Nigeria to investigate the reaction of ten cowpea breeding lines to infestation of Meloidogyne spp. Seven-day old seedlings were inoculated with 0 or 5000 eggs of Meloidogyne spp. The experiment was a 2 x 10 factorial, fitted into Randomized Complete Block Design laid out in the fields while the screen house trial laid in Completely Randomized Design. In each location, treatments were replicated four times. Data were collected on plant height, stem girth, root galls, number of days 50% to flowering, pods/plant and seeds/pod. Data obtained were subjected to Analysis of Variance. Statistically variable treatment means were separated using standard error of means at 5% level of probability. Results showed that Meloidogyne spp. induced stunting which results in poor growth and in severe cases affects the time of maturity on susceptible cowpea plants. Hence, highly nematode infested soil should be treated before sowing in order to ensure high qualitative harvest.

Keywords: Cowpea, Meloidogyne spp., plant height, stem girth