Ali, A. (2025). Resistance Development to Abamectin and Cross-Resistance to Multiple Insecticides in Rhynchophorus ferrugineus (Olivier), with Emphasis on Biochemical Analysis. Journal of Plant Protection and Pathology, 16(7), 381-390. doi: 10.21608/jppp.2025.397947.1356
A. M. Ali. "Resistance Development to Abamectin and Cross-Resistance to Multiple Insecticides in Rhynchophorus ferrugineus (Olivier), with Emphasis on Biochemical Analysis". Journal of Plant Protection and Pathology, 16, 7, 2025, 381-390. doi: 10.21608/jppp.2025.397947.1356
Ali, A. (2025). 'Resistance Development to Abamectin and Cross-Resistance to Multiple Insecticides in Rhynchophorus ferrugineus (Olivier), with Emphasis on Biochemical Analysis', Journal of Plant Protection and Pathology, 16(7), pp. 381-390. doi: 10.21608/jppp.2025.397947.1356
Ali, A. Resistance Development to Abamectin and Cross-Resistance to Multiple Insecticides in Rhynchophorus ferrugineus (Olivier), with Emphasis on Biochemical Analysis. Journal of Plant Protection and Pathology, 2025; 16(7): 381-390. doi: 10.21608/jppp.2025.397947.1356
Resistance Development to Abamectin and Cross-Resistance to Multiple Insecticides in Rhynchophorus ferrugineus (Olivier), with Emphasis on Biochemical Analysis
Plant Protection Department, Faculty of Agriculture, Minia University, Minia, Egypt.
Abstract
This study investigated the development and mechanisms of resistance to abamectin in Rhynchophorus ferrugineus larvae across eight generations (FS0-FS8) under laboratory selection. Abamectin resistance progressively developed, with the resistance ratio (RR) increasing from 1.06 in the initial field strain (FS0) to 51.18-fold by generation FS8. This significant escalation, coupled with decreasing probit slopes, indicated increased population heterogeneity and robust resistance development. Cross-resistance was also observed against other insecticide classes: hexaflumuron (RR = 105.91-fold), dimethoate (RR = 18.20-fold), and spinetoram (RR = 14.07-fold), highlighting broad-spectrum tolerance. Enzymatic analyses revealed significant up regulation of detoxification enzymes in resistant strains. Esterase activity increased 1.39-fold in RS5 and dramatically 6.09-fold in RS8 compared to the susceptible strain. Glutathione S-transferase (GST) activity increased 3.04-fold in RS5 and 2.84-fold in RS8, while oxidase activity (P450) showed the most consistent increase, reaching 1.84-fold in RS5 and over 3.9-fold in RS8. Acetyl cholinesterase (AChE) activity also increased, suggesting broader physiological adaptations. These findings strongly indicate that metabolic detoxification by esterases, GSTs, and oxidases are a primary mechanism driving abamectin resistance and cross-resistance in R. ferrugineus. Therefore, effective resistance management necessitates the implementation of diverse control strategies, including insecticide rotation, use of synergists, and integrated pest management approaches, to preserve the efficacy of current chemical controls and mitigate further resistance evolution.