Flufenoxuron induced male reproductive toxicity in Spodoptera Mauritia boisd Lepidoptera Noctuidae

Abstract

Insect pest infestations pose a significant challenge to global agricultural cultivations, particularly in rice production systems, necessitating effective pest management techniques to minimize losses and crop protection. Armyworm (Spodoptera mauritia Boisduval) is a sporadic pest that has emerged as a major pest in India, causing significant losses in wet-season rice production. Environmentally friendly pesticides, such as insect growth regulators (IGRs), interfere with insect growth and devélopment and are used toulternative to chemical pesticides. Disruption of insect growth and reproduction are the key mechanism of of different IGRs;among them chitisn systhesis inhibitors are aquired attentlons due their mode of action by targeting the insects chitin. Flufenoxuron, a third-generation chitin synthesis inhibitor, is a viable alternative against the control of several insects and mites. Therefore, in this context, the present study explored the effects of the insecticide chitin synthesis inhibitor, flufenoxuron, against the rice-swarming caterpillar and evaluated the effect on spermiogenesis as a model to illustrate male reproductive development. The current study showed that flufenoxuron adversely impacted the growth parameters required for male reproductive development. The sub-lethal effects of flufenoxuron significantly impaired the hatchability rate of eggs and lowered the number of fertile, normal adult insects. Moreover, flufenoxuron-treated sets showed a high sensitivity in biochemical indices to the impact of this pesticide. The treatment of the compound significantly depleted proteins, lipids, and carbohydrates in the testis and haemolymph, producing degenerated spermatozoa that may not produce healthy ‘ offspring. The results obtained from histo-morphological analysis and confocal image analysis confirmed that flufenoxuron suppresses differentiation of spermatozoa. Metabolomics analysis of S. mauritia haemolymph suggests that flufenoxuron can interfere with carbohydrate and lipid metabolic pathways and the chitin biosynthetic pathway, subsequently impacting the growth and reproduction of S. mauritia. The study aims to improve understanding of the regulation of reproduction, specifically male reproductive development triggered by chitin synthesis inhibitors, and promote the creation of endocrine disrupters as potential insecticides for controlling male insects.