Spatial prediction and delineation of Ginkgo biloba production areas under current and future climatic conditions

Abstract

Ginkgo (Ginkgo biloba L.) is an ancient medicinal tree species that is widely cultivated in China for its leaves which possess pharmacologically active metabolites. Knowledge about the effects of climate change on ginkgo leaf yield (biomass) and quality (target metabolites concentration) remains unknown. Here, we first examined the extent of several phenotypic traits (growth: leaf area and weight, main branch basal diameter and length; metabolites: concentration of flavonoids, ginkgolides, and polyprenols) variation of genetically homogeneous ginkgo clones (including gender differences) along climatic gradients. Second, we used univariate and bivariate modeling techniques to quantify the impact of several essential climatic factors on the performance of the studied phenotypic traits. Finally, we predicted the growth potential of the studied traits and delineated their suitable production areas under current and future climate conditions. Results showed that the studied 4 growth and 12 metabolites traits varied significantly (P < 0.05) among the 17 assessed diverse growing environments, while female trees consistently outperformed male trees for growth traits, but not for metabolites. Climate variables related to sub-zero temperature were considered to be the most key factor restricting the distribution of ginkgo (growth potential); however, they promoted the biosynthesis of some defense compounds (e.g., flavonoids). Future projections under the RCP8.5 scenario indicated that the area suitable for ginkgo growth (leaf area) would increase by mid-century as well the high-yield, high-quality areas of ginkgo cultivation would shift northward and upward.