Biocontrol of Cardamom Root Grub with EPN

Cardamom root grub, Basilepta fulvicorne Jacoby is a serious pest damaging cardamom roots, causing 10 - 70% yield loss under various levels of infestation. The pest has been managed with chemical pesticides viz. Chloripyrifos or Phorate. Since soil insecticides like phorate and carbofuran are highly toxic, and the government (Kerala) has banned these pesticides, biopesticides is an alternative and ecofriendly tool for sustainable management of this soil pest of cardamom. EPN or Entomopathogenic nematodes are parasitic on insect larvae. They are found in moist soil habitat and widely used for biological control of soil pests. A native species of EPN, Heterorhabditis indica (strain ICRI 18) extracted from cardamom soil, was found to be highly pathogenic and virulent on cardamom root grub.

With sponsorship from NABARD as well as DBT (Department of Biotechnology, Govt. of India) biological control of root grub was attempted. Entomopathogenic fungi, viz. Beauveria bassiana and Metarhizium anisopliae and also Entomopathogenic nematode (EPN), Heterorhabditis indica (strain ICRI 18) were found to cause mortality of the pest. Among them, EPN was found to reduce 70 - 100% of the pest in field condition.

Live and EPN affected grubs 

With the initial success, the Indian Cardamom Research Institute, ICRI (Spices Board, Ministry of Commerce & Industry) at Myladumpara, Kerala 685553 conducted demonstration trials in about 300 farmers' fields from 2006; apart from the demonstrations, ICRI distributed EPN to needy farmers on demand. The DBT task force who visited ICRI in 2010 was overwhelmed by the response of farmers demanding EPN for root grub management.