Incidence and intensity of root-knot and identity of species/races associated with vegetable crops in some districts of Uttar Pradesh, India

A survey was conducted in 9 districts of Agra and Bareilly divisions of Uttar Pradesh to determine incidence and intensity of root-knot disease and indentity of species and races of root-knot nematodes associated with vegetable crops. About 50% of the vegetable fields examined were found to be infested with root-knot nematodes. Incidence of the disease in the root samples was also about 50%. Eggplant and cucumber were most affected crops followed by tomato, pepper and okra. Root gall index/egg mass index ranged from 2–5/1–5. Meloidogyne incognita, M. javanica and M. arenaria were the species present in the area. M. javanica was most frequent followed by M. incognita and M. arenario. The species were encountered both in single or mixed populations. Of the 4 races of M. incognita detected in M. incognito populations of the area, race 2 was most frequent followed by race 1, race 4 and race 3. Race 2 alone comprised the M. arenario populations of the area.