Crop pest responses to global changes in climate and land management

Abstract

The prevalence of crop insect pests, which damage crops and reduce their yield, is increasing globally owing to changes in climate and land use, posing a threat to food security. In this Review, we synthesize evidence on how tropical, temperate, migratory and soil crop pests respond to changes in climate, land use and agricultural practices. In general, crop pests are responding to warming with expanded geographic ranges, advanced phenological events and increased number of reproductive generations per year. Increased pest damage under warming is projected to exacerbate yield losses of 46%, 19% and 31% under 2 °C warming for wheat, rice and maize, respectively. Pests at mid–high latitudes respond more positively to warming than those in the tropics. Moderate drought can increase pest damage to crops owing to enhanced feeding on plants as a water source and decreased resilience of plants and natural enemies of pests. Increased precipitation reduces small pests through washing them away, but favours pests in general through buffering thermal-hydro stresses. Land use change, such as deforestation and conversion to cropland, enhances warming and reduces biodiversity, leading to enhanced crop damage. Agricultural intensification, particularly fertilization and irrigation, increases the quality and quantity of host plants and buffers pests from environmental extremes, favouring proliferation. Globalization of trade networks increases pest invasions, with associated damage exceeding US $423 billion in 2019. Future research should examine the mechanisms underlying changes in pest status and develop monitoring and prediction systems to inform management approaches. Crop yield losses to insect pests pose a risk to food security. This Review assesses global trends of crop pest prevalence associated with global environmental change, identifies the underlying ecological mechanisms and proposes strategies for effective, sustainable management of pests to support future food security.