Insecticidal activities of the aqueous extracts of Chromolaena odorata leaves and Anacardium occidentale nutshell liquid against insect pests of cabbage and its effect on yield

The current study investigated the insecticidal potential of Anacardium occidentale and Chromolaena odorata in managing the main insect pests of cabbage in field settings. The 2018 and 2019 major and minor rainy seasons were when the study was carried out. Four treatments were used: a normal insecticide (Emamectin benzoate, 3 mL/L), a water extract of C. odorata leaves, a water extract of A. occidentale nutshell liquid (50 g/L), and soapy water as a control. Four replicates were used in a Randomized Complete Block Design (RCBD) arrangement for these. The quantity and presence of insects, an evaluation of leaf damage, and an estimation of harvest yield were the data collected. Thirteen different species of insects were recorded, and classified as major, minor, and beneficial pests. Plutella xylostella and Hellula undalis infestations in the control group were generally much greater than those in the other treatments. The botanicals were more successful than the control at reducing the aphid population. In general, the botanicals outperformed the control in terms of Phyllotreta sp. and ant population; however, there was no discernible difference in the response for Zonoceros variagatus and cabbage white flies. The mean weights, head diameters, and mean head heights for each treatment showed a significant difference (p < 0.05). For both seasons, more than 60% of the leaves had damage ranging from 0% to 20% (Damage 1). The results of this study demonstrate the two botanicals insecticidal properties against the most common insect pests of cabbage, allowing them to be included in an integrated pest management (IPM) package.