1Department of Agricultural Entomology, College of Agriculture, Vellayani, Thiruvananthapuram - 695 522, Kerala, India
2Department of Organic Chemistry, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram - 695 019, Kerala, India
3Department of Soil Science and Agricultural Chemistry, College of Agriculture, Vellayani, Thiruvananthapuram - 695 522, Kerala, India
Department of Nematology, College of Agriculture, Vellayani, Thiruvananthapuram-695 522, Kerala, India
*Corresponding authors' E-mail: nisha.das@kau.in
Online published on 26 September, 2025.
The study examines the use of Quassia indica Gaertn seeds for controlling the pumpkin caterpillar, a major pest of gourds. Lethal doses of different solvent extracts (n-hexane, acetone, ethanol and water) of Q. indica seeds were estimated and acetone extract exhibited lowest LD50 value (0.59%) against second instar larvae of Diaphania indica Saund at 72 h after treatment. Chromatographic fractions from the acetone extract of seeds @ 5% showed highest antifeedant (75.61% leaf protection) and insecticidal (73.33% mortality) effects against second instar larvae of D. indica. Nuclear Magnetic Resonance (NMR) analysis identified the presence of samaderins and cedronin in the seed extract.
Antifeedant, Botanical pesticide, Diaphania indica, Mortality, Quassinoids, Quassia indica, Seed extract
