Characterization of Triadica sebifera (L.) Small Extracts, Antifeedant Activities of Extracts, Fractions, Seed Oil and Isolated Compounds against Plutella xylostella (L.) and Their Effect on Detoxification Enzymes

Abstract

Plutella xylostella L. is one of the world’s major pests of cruciferous crops. The indiscriminate use of synthetic insecticides has led to insecticide resistance and resurgence, and has been harmful to non-target organisms and the environment. Botanical insecticides are the best alternatives to synthetic pesticides for the management of pests in organic agriculture and integrated management. T. sebifera is an invasive species and has good potential as an insecticide due to the availability of plant material in some parts of India. The antifeedant activities of T. sebifera have not been reported against P. xylostella and other lepidopteron insects to date. Therefore, the current study targeted the characterization of leaf and bark extracts, feeding deterrence, synergistic and detoxification enzyme activities of leaf/bark ethanolic extracts/fractions, seed oil, and isolated compounds. UHPLC-QTOF-IMS analysis showed that shikimic acid, xanthoxylin, quercetin, kaempferol, methyl gallate, and stigmasterol are common metabolites identified in leaf and bark extracts. The combination of seed oil with bark extract showed higher deterrence (DC50 = 317.10 mg/L) as compared to leaf/bark extracts alone. Gallic acid showed higher deterrence (67.48%) than kaempferol and quercetin. The n-butanol fraction of bark was more repellent (RC50 = 414.61 mg/L). Based on DC50, the seed oil with leaf extract (1:1 ratio) alone with choice and seed oil with leaf and bark extract without choice showed synergistic interaction, but seed oil with bark extract with choice showed additive interaction. The ethanol extract of leaf, bark, and seed oil inhibited GST and AChE in P. xylostella. The leaf extract and seed oil or their combinations may be recommended as antifeedants to reduce damage by P. xylostella based on persistence, antifeedant, phytotoxicity, safety to predators/parasitoids, etc., under field conditions.

Behavioral, Electrophysiological, and Toxicological Responses of Plutella xylostella to Extracts from Angelica pubescens

“…Novel pesticides to control P. xylostella are urgently needed to combat these environmental safety challenges. Previous studies have shown that plant extracts and derived bioactive compounds have a variety of biological activities to control pests, and they provide an alternative to synthetic insecticides due to their biodegradable nature and safety for non-target organisms [7,26,27].…”

“…Active compounds derived from plants or plant products have important bioactive functions and potential applications in agricultural pest management [4,27,31]. They often have a similar mode of action to synthetic insecticides [32], and may be able to provide precursor compounds for synthetic pesticides.…”

“…This depends on the chemical communication involved in P. xylostella egg-laying and feeding. For instance, Traiadica sebifera extract and its fractions showed antifeedant activities against P. xylostella larvae [27]. Ludwigia tomentosa and L. longifolia extracts showed oviposition deterrence and insecticidal activities against P. xylostella [7].…”

Genetic Engineering of Purslane (Portulaca oleracea L.)

“…In view of all the problems involved in the adoption of this control method, it is necessary to search for more sustainable measures as an alternative way to contain the attack of agricultural pests. A trend that has shown promise and is gaining space in the field of research is the investigation of the activity of botanical extracts against plant parasites [81].…”

Active defense strategies for invasive plants may alter the distribution pattern of pests in the invaded area

“…On this basis, the antifeedant effect of invasive plants can be tested by analyzing the damage pattern of native plants around invasive plants and then exploring the defense strategies of the invasive plants. Studies have documented antifeedant effects of invasive plants on herbivorous insects ( Liu et al., 2020b ; Dolma and Reddy, 2022 ). However, these studies mainly focused on the allelopathy of invasive plants and rarely involved the distribution patterns of native herbivorous insects that are impacted by invasive plants ( Liu et al., 2020b ).…”