Fig. 1: Historical wheat aphid loads in China and Europe by season.

Wheat aphid (log transformed) loads in different times of the year in China (a–i) and Europe (j–r) during 1970–2017. P and R2 values are from regressions. Lines indicate significant linear relationships between aphid loads and time. Including a random term for paper or for province (China) or country (Europe) makes the relationship in b not significant but the other significant relationships are unaffected.