Insecticide Resistance In Agricultural Pests: Mechanisms And Management

Abstract

Insecticide resistance is a significant challenge to the sustainable control of agricultural pests, exacerbated by intensive chemical application and low integration levels. The study assessed resistance levels, mechanisms, and management outcomes for the main agricultural pests across different areas using laboratory bioassays and molecular and biochemical tests, combined with management monitoring indicators. Resistance ratios (RR) varied among pest populations, ranging from 1.6 to 24.5. However, resistance was significantly higher for pyrethroids (average RR = 16.9 ± 3.6) and neonicotinoids (average RR = 13.8 ± 4.2) than it was for organophosphates (average RR = 9.7 ± 2.1) or diamides (average RR = 2.6 ± ANOVA; F =42; p <0.001). Resistance strength was highly correlated with target-site and metabolic resistance mechanisms, such as kdr mutation frequency (r = 0.71, p < 0.001) and cytochrome P450 levels of activity (r = 0.68, p < 0.001). In contrast, survival at the recommended field dose mortality decreased dramatically with increasing levels of resistance (r = −0.73, p < 0.001). Multivariate regression found that kdr mutations (β = 0.41, p < 0.001) and P450 activity (β = 0.36, p < 0.001), and integrated pest management (IPM) scores were the strongest independent predictors of resistance ratio, whereas they were inversely associated with resistance (β = −0.29, p = 0.002). Crop loss was positively associated with the level of resistance (r = 0.66, p < 0.001) but negatively affected by the extent of IPM adoption (r = −0.59, p < 0.001). Collectively, they reveal that insecticide resistance is a result of the interplay among several factors and that successful implementation of IPM can significantly reduce resistance levels and concomitant yield losses, supporting the important role of sustainable management of insecticide resistance.