Sustainable Crop Protection through Weed Valorization: Chemical Profiling and Bioactivity of Chenopodium Ambrosioides and Cleome Gynandra Against Insect Pests and Rice Root-Knot N`ematode

Abstract

Polar and nonpolar fractions of Chenopodium ambrosioides and Cleome gynandra were chemically profiled and evaluated as botanical crop-protection materials. GC–MS and LC–MS indicated chemically distinct fractions containing sterols, terpenoid derivatives, fatty acid esters, flavonoids, phenolic acids, glucosinolate-related features, oxylipin-related compounds, and glycolipid-related features. Bioassays showed dose-dependent mortality against Tettigonia viridissima, Tribolium castaneum, and Tuberolachnus salignus, with polar fractions generally showed higher activity than non-polar fractions. In aqueous assays, CA-PF and CG-PF caused direct mortality of Meloidogyne graminicola second-stage juveniles (J2s). Foliar application of polar fractions reduced nematode gall formation in rice and improved shoot and root biomass without visible phytotoxicity. DAB staining indicated localized hydrogen peroxide accumulation in treated leaves. These results support further chemical standardization and validation of Chenopodium ambrosioides and Cleome gynandra fractions as botanical crop-protection candidates.