Pathogenicity of ENTOMOPATHOGENIC nematodes against cabbage butterfly (PIERIS BRASSICAE) LINNAEUS (LEPIDOPTERA: PIERIDAE) in laboratory conditions

Cabbage butterfly (Pieris brassicae) is major pest of cabbage. More than 50% yield losses have been attributed due to this pest annually. Seven insect parasitic nematodes i.e. Steinerma carpocapsae, S. feltiae, S. Pakitananese, S. asiaticum, S. glaseri, Heterorhabditis bacteriophora and H. indica were evaluated on 4th larval instar of P. brassicae at the different concentrations. Two best performing EPNs (S. glaseri and H. bacteriophora) were selected and evaluated against 2nd, 3rd and 4th larval instars of Pieris brassicae at 1500 infective juveniles/ml. H. bacteriophora spp. and S. glaseri spp. were sprayed at 1500 IJs/ml on the cabbage leaves alone or in combination (S. glaseri + H. bacteriophora) and 2nd, 3rd and 4th larval instars were fed on them. Among seven EPNs, hundred percent mortality of P. brassicae was recorded in the case of H. bacteriophora and S. glaseri at1500 IJs/ml concentration after 48 h. Both EPNs spp. were found highly effective against all larval instars of P. brassicae. After 48 h of exposure of both EPNs spp. on all larval instar, 100% mortality was recorded. The combined application of H. bacteriophora + S. glaseri on cabbage leaves resulted into 100% mortality of all larval instars of P. brassicae. From present study, it may be concluded that H. bacteriophora and S. glaseri at 1500 IJs/ml concentration found very effective against P. brassicae in laboratory conditions and may be used in the field conditions.