Effect of Climate Change on Insect Pest Dynamics in Agro-ecosystems

Abstract

Climate change is reshaping insect pest dynamics in agro ecosystems through simultaneous shifts in temperature, precipitation patterns, atmospheric CO₂, and the frequency of extreme events. These drivers alter core biological processes—development rates, fecundity, survival, diapause, and dispersal—leading to earlier seasonal activity, increased voltinism, and expanding overwintering and establishment zones. At the same time, plants grown under drought and elevated CO₂ exhibit changes in nutritional quality and defense signalling that cascade to herbivores and their natural enemies, while heatwaves and compound events create nonlinear responses ranging from population collapse to explosive outbreaks. The aggregate result is a heightened and more variable risk landscape for crop damage, with pronounced effects in temperate production regions and along invasion frontiers. This review synthesises recent advances on the mechanisms linking climate drivers to pest population outcomes, highlighting how phenological shifts can decouple pests from hosts and natural enemies, how landscape simplification can amplify climate signals by weakening top-down control, and how biosecurity risks rise as establishment zones and migratory windows expand. We translate these insights into management guidance for climate-ready integrated pest management: climate-informed forecasting that integrates soil and air temperature products with drought and storm indicators; diversified portfolios that combine host resistance, cultural practices, and conservation biocontrol; resistance stewardship calibrated to faster generation turnover; and invasive-species surveillance based on climate-aware risk maps. Key research priorities include multi-stressor field networks that combine warming, drought, and elevated CO₂ with explicit trophic interactions; next-generation phenology and voltinism models that integrate photoperiod and extreme-temperature biology; and landscape-level designs that restore microclimate refugia and stabilise natural-enemy services. By coupling mechanistic understanding with operational decision support and co-designing adaptation strategies with growers, the agricultural sector can reduce pesticide reliance, preserve the durability of control tools, and safeguard productivity under a rapidly changing climate.