Control of Meloidogyne incognita (Kofoid and White) Population on Root Knot of Vigna unguiculata (L.Walp) (Cowpea) with Organic Soil Amendments

Abstract

A screen house experiment was conducted to determine the efficacies of leaf powder of Azadirachta indica (A.Juss.), Cassia siamea (Lamk.) and Eucalyptus gigantean (Dehnh) in the control of Meloidogyne incognita on cowpea. Three different doses viz. 25, 50 and 75g of each of the leaf powder was separately mixed with 4kg of soil in a 25cm diameter plastic pot. Non-amended pots served as control. Three cowpea seeds were sown in each pot but the seedlings were thinned to one plant per pot. Each seedling was inoculated with about 3000 freshly hatched juveniles of Meloidogyne incognita. The experiment was laid out in completely randomised design with five replications and data obtained was analysed using ANOVA and means were significant were separated using the Duncan’s multiple test. The result of the study showed that all the treatments significantly (p?0.001) reduced root galling, nematode population and improved growth and yield of cowpea. Although all treatments were effective in reducing root galling and nematode population, application of Azadirachta indica leaf powder gave the highest reduction in nematode population, followed by Cassia siamea and Eucalyptus gigantea.

Keywords: Vigna unguiculata, Meloidogyne incognita, Azadirachta indica, Cassia siamea, Eucalyptus gigantea.