Thalictrum foliolosum DC against aphid, Aphis craccivora Koch and mealybug, Planococcus lilacinus Cockerell: A potential bioinsecticide

Aphis craccivora and Planococcus lilacinus are significant plant virus carriers and severe pests of legumes, fruits, and commercial crops. Inappropriate use of inorganic pesticides for the management of pests leads to resistance, detrimental to natural enemies of pests and the environment. In this study, methanolic root extract, different fractions, and isolated compounds from Thalictrum foliolosum DC were investigated for their pesticidal and enzyme inhibition potential against target pests. The findings revealed that thalidasine and berberine were most effective against A. craccivora (LD₅₀ = 0.43–0.47 μl/insect), followed by n-butanol fraction (LD₅₀ = 1.37 μl/insect). Similarly, the aqueous fraction was more promising against P. lilacinus (LD₅₀ = 0.24 μl/insect) as compared to jatrorrhizine and thalidasine (LD₅₀ = 0.60–0.64 μl/insect). Further UHPLC-PDA-based analysis revealed that chloroform fraction showed higher thalidasine (37.86 ± 0.923 mg/g) and berberine (37.76 ± 0.398 mg/g) content, whereas berberine (36.06 ± 0.045 mg/g) also quantified in dominating amount in n-butanol fraction, together with jatrorrhizine (23.74 ± 0.177 mg/g). In reproduction inhibition assay, the chloroform and methanol extract showed a higher inhibition rate at 10 000 mg/L (98.69–99.46%). Additionally, methanolic extract significantly inhibited the detoxifying enzymes (glutathione S-transferase and acetylcholinesterase) in target pests. Therefore, based on field bio efficacy data of extract/fractions and compounds, the lead (s) can be employed further for the preparation of botanical insecticide. The present finding provides the first report on simultaneous quantification of three isoquinoline alkaloids by UHPLC-PDA and the bio-insecticidal potential of T. foliolosum.