Biomanagement of Reniform Nematode, Rotylenchulus reniformis on Cowpea (Vigna unguiculata) by Neem

Two glass house experiments were conducted to study the impact of neem (Azadirachta indica) leaf extract and leaf powder on Rotylenchulus reniformis infecting cowpea. Aqueous leaf extract of neem was applied as foliar and soil application at two concentrations (10 and15%). Soil application with 15% extract recorded maximum growth parameters and yield (25.5 g/plant) and minimum nematode population in soil (109.5/250 cc) and root (10/g). Foliar application also showed significantly higher growth parameters and lesser nematode population compared to control. In another experiment, neem leaf powder as seed treatment at 10% w/w recorded the highest growth parameters and yield (36.5g/plant) and the lowest nematode population in soil (43.5/250 c.c.) and roots (3.5/g).