<div>Background: The cabbage webworm, Hellula undalis (Fabricius) (Lepidoptera: Pyralidae) is destroy insect pest in vegetable crops. Vegetable growers spray many kinds of chemical pesticides to control this insect pest. The objective of this study was to investigate the efficacy of the extract from pongam leaves, Progamia pinnata L. against the cabbage webworm.&nbsp; 
 
Methods: The experiment was carried out at the Laboratoty of Entomology, Faculty of Agronomy, University of Agriculture and Forestry, Hue University, Vietnam during 2020 and 2021. Different concentrations of pongam leaf extract was tested its efficacy against first and second instar larvae of the cabbage webworm on potted plants of leaf mustard, Brassica integrifolia West. 
 
Result: The efficacy of pongam leaf extract was more efficacious against the first instar than the second instar of H. undalis. At five days after treatment, the efficacy of the pongam leaf extract against first and second instars of H. undalis was 93.2 and 68.4% at concentrations of 1.0%, respectively. Therefore, the pongam leaf extract can be recommended as potential botanical insect ides to control the cabbage webworm.</div>

Larvicidal Activity against the Cabbage Webworm, Hellula undalis (Fabricius) (Lepidoptera: Pyralidae) of the Extract from Pongam Leaves (Pongamia pinnata L.)