Field and Laboratory Studies on the Toxicity of Lambda-Cyhalothrin for Controlling Desert Locust (Schistocerca Gregaria)

Abstract

Desert locust has negative impact on world vegetation, severely affected Africa and Asia in 2020-21. The pest persists in both gregarious and solitary forms. In Pakistan, the majority of the nation experienced a desert locust attack in 2020. Seven to ten districts in Khyber Pakhtunkhwa were seriously impacted. The study was carried out to test the efficacy of different concentrations of Lambda-cyhalothrin 2.5 EC against adult and hoppers/nymph in field and laboratory conditions. The applied concentration was 4%,3%, 2%, 1% and 0.5 % for adults in field and lab conditions, while 2%, 1.5%, 1%, 0.5% and 0.25% for nymph’s trials. Under field condition against adults all the applied concentrations were at par with each other except 0.5%, which showed significantly lower mortality rate (60%). A similar trend of toxicity was also recorded for the laboratory trials. More than 85% mortality was recorded in all treatment except 0.5%, which was 65%. Against hopper all concentration showed significant higher mortality (above 80%) except the nymphs sprayed with 0.25% concentration under field conditions. Similar results were also obtained for vitro trials against nymphal stage. It is concluded an average concentration (3%) should be applied for adult to avoid resistance and pest escape. For hoppers/nymph the recommended concentration should be 1%. Further studies should be carried out regarding the resistance to different types of insecticides under field and laboratory conditions.