Effectiveness, characterization and optimization of botanical extracts: An ecofriendly approach for management of thrips infestation on tea in Bangladesh

Abstract

In the realm of agricultural pest management, the exploration of eco-friendly solutions remains paramount. This study delves into the efficacy of botanical extracts derived from medicinal plants in combating thrips infestation on tea plants (Camellia sinensis L.) in Bangladesh. Through meticulous experimentation, this study found Sapium indicum (Willd.) to be the most effective plant extract, followed by Ipomoea carnea (Jacq.) and Lantana camara where the LC₅₀ values were recorded as 431.28 ppm, 590.83 ppm, and 1329.03 ppm, respectively after 24 h of exposure. Additionally, volatile compounds of S. indicum showed the highest thrips control efficacy, approximately on average 75 % mortality, while having the lowest CV. Notably, under optimized conditions of 24.4 h stirring time, 56.8 °C, and 54.8 % ethanol concentration, S. indicum extract achieved 89.55 % efficacy whereas leaving minimal soil residue (43.4 mg/kg), demonstrating both its potency and low environmental persistence. Gas chromatography-mass spectrometry (GC-MS) was used to conduct chemotaxonomic analyses, revealing isobutyl tiglate as a particularly potent component, alongside 2-methyl-2propyl-1,3-propanediol, showcasing promising efficacy against tea thrips. These insights underscore the potential of botanical extracts as sustainable and eco-friendly alternatives for thrips management in agricultural ecosystems, while advocating for the integration of chemotaxonomic approaches in shaping effective pest control strategies.