Community Structure of Nematodes Associated with Vegetable Crops in Kerala

AbstractSurveys were undertaken to determine the occurrence and identity of predatory and other nematodes associated with the cultivation of vegetable crops like ivy gourd, snake gourd, bitter gourd, ash gourd, ridge gourd, pumpkin, cucumber, chilli, brinjal, tomato, okra, cowpea, cauliflower, colocasia, elephant foot yam, amaranthus, and Malabar spinach cultivated in different AEUs of Kerala. Among the predatory mononchids, Mononchus aquaticus, Mylonchulus minor, Actus salvadoricus, Sporonchulus ibitensis and Iotonchus indicus were found to occur in different AEUs. Dorylaimids, Aporcelaimids and Actinolaimids were the other predatory fauna recorded. Community analysis of nematodes was computed for eight blocks falling under five districts of Kerala. The results revealed that nematodes of the Order Rhabditida were the most prominent nematode fauna in Athiyannur, Vamanapuram, Bharanikkavu and Sulthan Bathery blocks. Among the predatory mononchids, Mylonchulus minor were frequently recorded in Nemom and Vamanapuram blocks; Iotonchus indicus and Actus salvadoricus were prominent in the Nemom block of Thiruvananthapuram district. Among the dorylaimid nematodes, individuals belonging to family Dorylaimidae were prominent in Nemom block; Aporcelaimid nematodes in the Vamanapuram block; Actinolaimds in Sulthan Bathery block and other dorylaimid nematodes were abundant in Irikkur block. Highest populations of predatory and plant parasitic nematodes were recorded in the Thiruvananthapuram district, whereas, lowest in the Wayanad district.