Virulence of Native Isolates of Entomopathogenic Nematodes for the Management of White Grubs

An alternative to chemical control, entomopathogenic nematodes are very effective against insect pests. Native isolates of Steinernema siamkayai, S. carpocapsae, Heterorhabditis indica, H. bacteriophora, Heterorhabditis sp. and Oscheius sp. have been evaluated for their virulence against white grubs. Under laboratory conditions, S. glaseri was more susceptible to A. communis in potato. S. glaseri @ 2.5 × 10⁹ IJ/ ha showed the highest grub mortality of 83.33% and 19.04% tuber damage. The same dosage of Heterorhabditis sp. in pot culture caused 18.66% tuber damage and 74.05% larval mortality. Steirnernema glaseri and Heterorhabditis sp. effectiveness against the coleopteran insect pests of Anomala communis in potato was conducted under field conditions. The maximum grub mortality with S. glaseri at 2.5 × 10⁹ IJ/ ha was 71.33%. With Heterorhabditis sp. at 2.5 × 10⁹ IJ/ ha, the yield increased by 14.14 t/ ha while tuber damage was 24.99%. However, the nematode S. glaseri and Heterorhabditis sp. has its best ability to live at the lowest temperature in the field trial, Anomala communis was successfully managed by S. glaseri followed Heterorhabditis sp. in potato. The natural distribution of the native isolates of EPNs may be used for local insect pest management.