Crop rotation systems and population levels of nematodes

Abstract

The effect of crop rotation involving tomato, corn and velvet bean (Mucuna deeringiana) on the population levels of Meloidogyne incognita and Rotylenchulus reniformis and on crop yield was studied for 2 years in the Isabela area. Meloidogyne incognita and R. reniformis population levels were drastically reduced in all rotations with velvet bean and corn, whereas a considerable increase was obtained from plots with continuous tomato. In the fourth planting (second year), the tomato roots from plots previously planted to velvet bean showed significantly smaller gall index values than those in the other treatments. The yields of tomato from plots previously planted to velvet bean or corn were significantly higher than those from plots planted to continuous tomato or from nematicide-treated plots.