Adaptive genetic variation in the smoke tree (Cotinus coggygria Scop.) is driven by precipitation

• We found significant population differentiation within Cotinus coggygria.
• The populations of C. coggygria were divided into two gene pools.
• Precipitation is a key factor in C. coggygria adaptive genetic differentiation.

The landscape genetics of a widespread and locally adaptated species increases the understanding of the adaptive evolutionary process of local flora and vegetation. In this study, we selected Cotinus coggygria, which is widespread and locally adaptated species in China's warm-temperate zone, to investigate its landscape genetic pattern. We used eight microsatellite loci to examine the adaptive genetic variations of C. coggygria. A total of 43 microsatellite alleles were genotyped in 142 individual plants from 16 wild populations. The data demonstrated significant population differentiation within C. coggygria, which was caused by geographical distance, human activities, and precipitation. Five ecologically relevant microsatellite alleles, which were all related to the precipitation, were identified by association analysis. Our results indicate that precipitation is an important factor that drives adaptive genetic differentiation in C. coggygria.