Efficacy of botanical extracts was evaluated against the rice stem borer Scirpophaga incertulas (Wlk.) at PAJANCOA and RI, Karaikal during kharif 2019 and rabi 2019-2020. The results revealed that thiamethoxam 25WG @ 100 g/ ha reduced incidence to 4.99% and 4.13% (52.15 and 61.80% reduction, respectively). Among the botanicals, garlic and chilli extract 5% reduced this to 5.69% and 5.48%. The predatory coccinellids and spiders were more in untreated check and it was found at par with garlic and chilli extracts at 5%, followed by five leaf extracts @10% and bitter apple leaf extract 10%. The benefit cost ratio (BCR) was maximum with thiamethoxam 25WG @ 100 g/ ha (1: 1.67 and 1: 2.10), followed by garlic and chilli extract 5% (1: 1.59 and 1:1.91).

The use of synthetic insecticides is one of the most widely used strategies to control wax moth infestations. However, toxicity to bees and contamination of their products have been considered to be consequences of insecticide residues, increasing the risk of hazards to human health and environment. Here, we evaluated the application of plant extracts and essential oil would be selective against the honey bees Apis cerana indica L. without compromising the control of the wax moths Galleria mellonella. In that, peppermint oil (1.25%) and Azadirachta indica (3%) caused 53.33% and 40.00% mortality. Whereas, eucalyptus oil (1.25%), Ocimum tenuiflorum (3%) extract caused 33% wax moth mortality. But in contact toxicity, peppermint oil and eucalyptus oil (5%) caused highest larval mortality 80% and 72.38%, O. tenuiflorum at 10% concentration recorded 56.19% mortality. In repellence bioassay, peppermint oil (1.25%) and A. indica (3%) caused 100% repellence. Whereas, at 10% concentration only O. tenuiflorum caused 100% repellence. Furthermore, O. tenuiflorum (10%), A. indica (10%), peppermint oil (2.5%) and eucalyptus oils (2.5%) did not kill honeybee but did exhibit insecticidal and repellent activities against the larvae and adults of wax moth. By exhibiting desirable levels of selectivity against A. cerana indica and providing relevant control levels against wax moths, the application of O. tenuiflorum leaf extracts and pepper mint essential oil represents a desirable tool to replace the use of synthetic insecticides against wax moths in weak honey bee colonies as well as in stored honey bee combs.