Distribution of root-knot nematode on major field crops in Uttar Pradesh (India)

Abstract

An extensive survey was conducted (2007–2009) to assess the incidence and intensity of root-knot disease on field crops especially rice and vegetable crops in 21 districts, representing the major production centre in Uttar Pradesh (India). Based on incidence, population density and associated damage on affected crops, Meloidogyne species were considered to be the most important parasites of the crops under local condition. The increasing occurrence and damage of this nematode to tomato, rice, brinjal, okra, cowpea, cucurbits, onion, pumpkin and bitter gourd grown in northern India was recently documented. Heavy galling was caused in many crops including rice, tomato, okra, cowpea, onion, pumpkin, brinjal and bitter gourd; also root decay or reduced root system was common among these crops. Attacked plants had yellowish foliage, unthrifty growth and small slow growing fruits and poor yields. The extent of crop losses depends on the initial nematode population, susceptibility of the crop, cropping sequence, age of the plants, soil fertility and involvement of secondary pathogens.