Effect of sublethal doses of some insecticides and their role on detoxication enzymes and protein-content of Spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae)

Abstract

Background: The indiscriminating and intensive use of insecticides to control the cotton leafworm (CLW), Spodoptera littoralis (Boisduval) (Lepidoptera: Noctuidae), usually induces high levels of resistance. The insecticides are the principal method for controlling this pest because of its critical role in reducing insects when the economic threshold (ETL); therefore, the effectiveness of these insecticides should be maintained. So, the target of the present work was directed to focus on studying the change in the activities of some important enzymes as a result of sublethal treatment concentrations (viz. LC 25 values) of tested new insecticides (profenofos, cyfluthrin, emamectin benzoate, lufenuron, and spinetoram). The expected results could offer better understanding and more specific information about the resistance development in field populations of CLW because resistance is a significant challenge to pest control workers and these results may contribute to making the right decision at the right time. Materials and methods: Bioassays were performed on fourth instar larvae of S. littoralis field populations compared with the laboratory strain to assess the activity of the emamectin benzoate, lufenuron, and spinetoram by LC 25 and study the biochemical activities of some detoxification enzymes, like acetylcholinesterase (AChE), glutathione S-transferases (GST), alkaline phosphatase (ALP), and acid phosphatase (ACP) in fourth larval instar which was treated with LC 25 ; protein content is also determined.

Role of Insect Gut Microbiota in Pesticide Degradation: A Review

“…Detoxification enzymes occur naturally in various biological processes, functioning on the target sites to neutralize various toxins prevalent in the insect body ( Lin et al, 2015 ; Bhandari et al, 2021 ; Siddiqui et al, 2022 ). According to some previous studies, the biochemical characterization of insect resistance to pesticides is connected to pesticide sensitivity at the target site and pesticide detoxification by metabolic enzymes (acetylcholinesterase, carboxylesterase, glutathione S-transferase, and cytochrome P450) ( Wu et al, 2014 ; Ismail, 2020 ; Yang et al, 2021 ; Siddiqui et al, 2022 ). These enzymes are crucial in detoxifying xenobiotics ( Hu et al, 2014 ), where their hosts can utilize these enzymes as biological indicators during pesticide detoxification ( Khan et al, 2021 )—for instance, Zhang et al (2016) reported that detoxification enzymes (cytochrome P450 genes) were detected during detoxification of fipronil in the red imported fire ants ( Solenopsis invicta Buren), where up to 36.4-fold rise in resistance was recorded following exposure of the ants to fipronil.…”

Contribution of insect gut microbiota and their associated enzymes in insect physiology and biodegradation of pesticides

“…Resistance and detoxification of pesticides and many more (Ismail, 2020;Clark et al, 2021;Ahmad et al, 2022b;Siddiqui et al, 2022). Insect pests' resistance against different pesticides by insect gut microbial enzymes was reported (Table 2).…”

Investigation of secondary metabolites in bean cultivars and their impact on the nutritional performance ofSpodoptera littoralis(Lep.: Noctuidae)

“…Besides, it can reduce the photosynthetic area and growth rate of more than 100 plant species in 40 families as a leaf feeder and cutworm on seedlings and bolls (Pluschkell et al ., 1998; Darvishzadeh, 2014). The use of synthetic insecticides, a common strategy to control S. littoralis , has led to the development of insecticide-resistant insects (Wei et al ., 2018; Ismail, 2020). The long-term use of pesticides also has a negative effect on the environment, natural enemies of the pest, and human health (Le et al ., 2010; Radwan et al ., 2019).…”