Status of root-knot nematode (Meloidogyne species) disease in vegetable crops of some districts of central plain region of Chhattisgarh State, India

The root-knot nematodes (Meloidogyne species) are economically important pathogens, especially infesting vegetable crops. In the tropics and subtropics, Meloidogyne incognita causes an estimated yield loss of 5 to 43% in vegetable crops. In the present study, root-knot nematode disease was surveyed in various vegetable crops in the central plain region of Chhattisgarh State. Roots and rhizosphere soil samples were collected from 44 farmlands representing five districts of Chhattisgarh during mid cropping season. Nematodes were extracted by Cobb’s sieving and decanting method, followed by modified Baermann’s funnel technique. Out of 44 samples, 24 showed the root-knot nematodes infection with an overall incidence of 54.54%. The percent incidences of disease ranged between 30 and 80% in five districts. Out of 13 species of vegetable crops surveyed, nine were observed to be infected. The most frequently occurring species was Meloidogyne incognita (63.33%), followed by Meloidogyne arenaria (20%) and Meloidogyne javanica (16.67%). Maximum frequency was observed in Lageneria siceraria (100%), and least was Musa paradisiaca, Daucus carota and Amaranthus tristis (50%). The mean population density of 2nd stage nematodes ranged between 766 and 9076 nematodes/200 cc soil and 10 g roots in samples.   Key words: Root-knot nematode, survey, Meloidogyne spp., incidence, frequency, Chhattisgarh.