Evaluation of bio-agents, synthetic insecticides and organic amendment against the root-knot nematode, Meloidogyne spp. in cardamom [Elettaria cardamomum (L.) Maton]

 Investigations were made to study the effects of three nemato-pathogenic fungi viz. Purpureocillium lilacinum, P. lilacinum + neem cake, Pochonia chlamydosporia and Trichoderma sp. as well as two synthetic insecticides (cartap hydrochloride and carbosulfan) against the Root-knot Nematodes (RKN) of cardamom at the farmers’ fields in three locations of Idukki district, Kerala, India during 2016- 2019. Results revealed that the combined application of P. lilacinum with neem cake gave maximum reduction of typical symptoms of infestation like the leaf narrowing (6.42%) and root knot formation (1.32 nos.) followed by P. chlamydosporia with 8.04% narrowed leaves and 1.83 root knots. The application of P. lilacinum and neem cake in combination (0.82 kg/plant and 2.99) followed by P. chlamydosporia (0.71 kg/plant and 2.71 recorded highest yield and Benefit Cost Ratio, respectively). Bio-control agents are therefore efficient and environmentally safer for managing the RKN in cardamom. Future studies can be directed to focus on the compatibility and efficiency enhancement of these bio-agents with organic amendments.