Impact of global warming on cereal aphids

Author of the article:MA Chun-Sen1** MA Gang1 ZHAO Fei2

Author's Workplace：1. State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China; 2. Shanxi Key Laboratory of Integrated Pest Management in Agriculture, Institute ofPlant Protection, Shanxi Academy of Agricultural Sciences, Taiyuan 030031, China

Key Words：climate change, temperature, aphid, impact, thermoregulation, adaptation

Abstract：

     Cereal aphids have a small body size and short life cycles which make them sensitive to ambient temperature change and brief heat exposure. Temperature increases caused by global warming are therefore a key factor impacting on cereal aphids directly. This paper reviews field observations, prediction models and simulated experiments concerning the effects of global warming on cereal aphids. Warming has caused the distribution of this species to shift to higher latitudes. Increases in the effective accumulated temperature in growing seasons have advanced some stages of the aphids’ life-cycle, such as the time of first occurrence and migration. Warmer winters have increased aphids’ overwintering survivorship and led to increases in population density in temperate regions. Interspecific interactions between cereals, aphids and natural enemies may be affected by global warming due to differences between species at different trophic levels. Cereal aphids have poor heat resistance and are consequently very vulnerable to the main characteristics of warming, such as increases in temperature, heat duration, nighttime minimum temperature and the intensity and frequency of extreme events. The intensity and duration of high temperature depressed aphids’ survival and reproduction. Night warming on hot days decreased aphids’ survival and exacerbated the adverse effects of daytime high temperatures. Changes in the frequency and amplitude of extreme high temperatures altered the temporal and spatial structure of the aphid community, and these changes are driven by the asymmetric effects of high temperatures on the demographic rates and fitness of different species. Aphids were found to respond to heat stress by behavioral thermoregulation, highlighting the importance for considering the buffering effects of cereal aphids against climate warming. Future research should include how to mimic realistic temperature changes that can reflect the key characteristics of climate warming, test the effects of these on aphids’ performance and the potential adaptations of aphids to climate warming.