Multidecadal, continent-level analysis indicates agricultural practices impact wheat aphid loads more than climate change
Xiao, Sun et al. (2022), Multidecadal, continent-level analysis indicates agricultural practices impact wheat aphid loads more than climate change, Dryad, Dataset, https://doi.org/10.5061/dryad.80gb5mks6
Temperature has a large influence on 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 how climate and agricultural practices affect populations of wheat aphids. Here we showed that aphid loads on wheat had distinct patterns between these two regions, with a significant increase in China but a decrease in Europe over this time period. Although temperature 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 long-term data suggest that agricultural practices impact wheat aphid loads more than climate warming.
We used regression analyses to examine how the abundance of aphids (log transformed) depended on year separately for each ~ten-day period in which aphids were present at least at some of the sites (March to May for China and May to July for Europe). To control for multiple points from the same study, we used the average value for each study for each year and ten-day period. We performed another set of regressions to examine how the abundance of natural enemies depended on year separately for each ten-day period in which they were present at least at some of the sites in China (April to May). In these analyses, we treated each 10-day time period separately and used averages for each year and 10-day period. We used the slopes of regressions to test for differences between the temporal pattern of change over years between China and Europe and among early, mid and late season aphid abundances in China and Europe. We considered an effect to be significant when the 95% CI did not overlap zero and we considered two intervals to be different when their 95% CIs did not overlap. We tested whether a country or provinces rate of change in aphid loads was correlated with its rate of change in temperature. We performed a mixed model ANOVA to test whether the proportion of area under cultivation depended on year for China provinces vs. European countries and used slope contrasts to test whether the slopes for China vs. Europe differed on average. We also tested whether slopes for individual countries or provinces differed from zero.
The software of word and Excel could open the data files.
National Key Research and Development Program, Award: 2017YFD0200600
Program for Science & Technology Innovation Talents in Universities of Henan Province, Award: 22HASTIT039
Young Talent Support Project of Henan Province, Award: 2021HYTP034
National Postdoctoral Program for Innovative Talents, Award: BX201700069