AUTHOR=Shyam-Sundar Narayanan , Ramasubramanian Ramakrishnan , Karthi Sengodan , Senthil-Nathan Sengottayan , Chanthini Kanagaraj Muthu-Pandian , Sivanesh Haridoss , Stanley-Raja Vethamonickam , Ramkumar Govindaraju , Narayanan Kilapavoor Raman , Mahboob Shahid , Al-Ghanim Khalid Abdullah , Abdel-Megeed Ahmed , Krutmuang Patcharin TITLE=Effects of phytocompound Precocene 1 on the expression and functionality of the P450 gene in λ-cyhalothrin-resistant Spodoptera litura (Fab.) JOURNAL=Frontiers in Physiology VOLUME=13 YEAR=2022 URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2022.900570 DOI=10.3389/fphys.2022.900570 ISSN=1664-042X ABSTRACT=

Spodoptera litura (Fabricius) is an agriculturally significant polyphagous insect pest that has evolved a high level of resistance to conventional insecticides. A dietary assay was used in this work to assess the resilience of field populations of S. litura to λ-cyhalothrin. Analysis of the function and expression of the cytochrome P450 gene was used to test the sensitivity of S. litura larvae to sub-lethal concentrations of the insecticidal plant chemical Precocene 1, both by itself and in combination with λ-cyhalothrin. The activity of esterase enzymes (α and β) was found to decrease 48 h post treatment with Precocene 1. The activity of GST enzyme and cytochrome P450 increased with Precocene 1 treatment post 48 h, however. Expression studies revealed the modulation by Precocene 1 of cytochrome P450 genes, CYP4M16, CYP4M15, CYP4S8V4, CYP4G31, and CYP4L10. While CYP4M16 expression was stimulated the most by the synergistic Precocene 1 + λ–cyhalothrin treatment, expression of CYP4G31 was the most down-regulated by Precocene 1 exposure. Hence, it is evident that λ–cyhalothrin-resistant pest populations are still sensitive to Precocene 1 at a sublethal concentration that is nevertheless capable of hindering their development. Precocene 1 can therefore be considered a potent candidate for the effective management of insecticide-resilient S. litura.