Multidecadal, Continent-level Analysis Found No Impact of Climate Warming on Wheat Aphids

Temperature drastically determines insect abundances, thus under climate change, identifying major drivers affecting pest insect populations is critical to world food security and agricultural ecosystem health. Here, we conducted a meta-analysis with data obtained from 120 studies across China and Europe from 1970 to 2017 to reveal the roles of climate and agricultural practices in determining populations of wheat aphids. We showed aphid loads on wheat had distinct patterns between these two regions, with a significant increase in China but decrease in Europe over this time period. Although average winter and growing season temperatures increased over this period in both regions, we found no evidence showing climate warming affected aphid loads. Rather, differences in pesticide use, fertilization, land use, and natural enemies between China and Europe may be key factors accounting for differences in aphid pest populations. These findings provide insights for developing effective agroecosystem management under global change. These long-term data suggest that climate change may not be the most important driver of agricultural pest loads. Therefore, under global environmental change, consideration of multiple factors at large spatial-temporal scales will likely provide more insights for developing effective agroecosystem management to safeguard world food security.