Survey of plant-parasitic nematodes associated with four vegetable crops cultivated within tunnels

A survey was conducted during 2010-11 to determine the occurrence and population density of plant-parasitic nematodes on four vegetable crops including cumber (cucumis sativus),tomato,(lycopersicum esculentum),chili and bell peppers (capsicum frutescens) cultivated under plastic tunnels. major vegetable growing regions of faisalabad,jhang,kasur,lahore,n-sahab,sargodh,t.t. singh,and sheikhpur were included in our survey. the survey revealed the presence of nine species of plant-parasitic nematodes viz.,aphelenchus avenae,helicotylenchus dihystera,hoplolaimus columbus,meloidogyne javanica,m. incognita,pratylenchus penetrans,radopholus smilis,tylenchorhynchus claytoni and xiphinema sp. frequency and density of each species were highly variable from field to field and within the fields. foliage growth was not uniform in the surveyed fields under tunnels where stunted growth,chlorotic leaves and wilted plants with fewer fruits were observed in patches. the stunted and poorly growing plants exhibited arrested root systems with reduced number of feeder roots; root galling and brown lesions were also evident.