Wasps are excellent predators of pests and can play a big role in controlling them: IISc professor

Wasps have a great potential to be beneficial insects and can play a larger ecological role in controlling pests, said Raghavendra Gadagkar, professor and National Science Chair, Centre for Ecological Sciences, IISc.

Delivering the T.N. Ananthakrishnan Birth Centenary Lecture on “You are how much you eat: Caste and nutrition in the Indian paper wasp, Ropalidia marginata”, Dr. Gadagkar said that for a long time the focus on beneficial insects has been bees and that nobody really looked at the wasps.

Larger ecological role

“But in recent years it has been recorded that wasps are excellent predators of pests and they are being used now for pest control. In the last five to 10 years people have woken up to the possibilities of wasps playing a larger ecological role especially in terms of pest control,” Dr. Gadagkar said.

He added that nutrition is the key and that wasps which eat more become egg-layers, and well-fed larvae develop into adults who feed more and become egg layers.

“Wasps who feed more develop ovaries early. Behaviourally dominant and well- fed wasps tend to leave their natal nets to find new nests either alone or jointly. They prepare for this future by altering their behaviour both on and off the nest,” he added.

Specialised tasks

Dr. Gadagkar said that division of labour is a fundamental property of social insects and different individuals specialise in different tasks. “Such differentially specialised individuals are termed castes,” Dr. Gadagkar said.

S.N. Puri, former Vice-Chancellor, MPKV, Rahuri & Central Agricultural University, Imphal, emphasised the importance of research on technologies used in natural farming and standardisation of drone application for delivering various biocontrol agents.

NPS scheme

J.P. Singh, Plant Protection Advisor, Government of India, briefed about the National Pest Surveillance Scheme (NPSS) and stressed the importance of pest scouting for deciding the right dose and use of pesticides by the farmers.