Assessment of Nematode Distribution and Yield Losses in Vegetable Crops of Western Uttar Pradesh in India

Plant-parasitic nematode population densities were determined from 412 root and soil samples collected from vegetable growing areas of Western Uttar Pradesh province of India. The most abundant plant-parasitic nematodes detected, in order of decreasing frequency of infestation (percentage of samples), were Meloidogyne incognita (82.16 %), M. javanica (68.42), Rotylenchulus reniformis (43.98 %), Xiphinema basiri (23.45 %), Hoplolaimus indicus (21.99 %), Tylenchorhynchus nudus (16.60 %), Pratylenchus zeae (15.77 %), Heterodera avenae (7.88 %), Aglenchus costatus (7.47 %), Tylenchorhynchus mashoodi (6.64 %), Aphelenchus avenae (5.39 %), Discolaimus (4.15 %), Boleodorus similis (3.32 %), and Tylenchus (2.07 %). Yield losses associated with nematode presence were quantified on 17 vegetable crops during 2012 to 2015. Based on our visual field observations and grower responses the average percentage of production losses due to nematode was 23.70 % for 17 vegetable crops in Western UP, which ranged from 4 % for bitter gourd to 43 % for egg plants. Maximum yield loss of 43 % was observed in eggplant followed by 40 % in tomato, 38 % in okra, 35 % in bottle gourd and 32 % in potato. Bitter gourd and cabbage were found to have insignificant yield losses of only 4 % and 6 % respectively.