Species diversity and floristic characteristics of Actinidia in Zhejiang Province, China

Actinidia is a genus of significant economic and ecological value in China. Comprehensive analyses based on extensive field surveys, herbarium records, and published literature were conducted to assess the spatial distribution patterns and floristic attributes of Actinidia in this region. A total of 11 species and two varieties were identified, representing approximately 17.3% of the known taxa in the genus. Contrary to previous reports, no wild populations of A. latifolia (Gardn. et Champ.) Merr., A. callosa Lindl., or A. callosa Lindl. var. henryi Maxim. were confirmed. Species richness was highest in the Donggong Mountain area (approximately 12 species or varieties), followed by the Xianxia Mountain area (10), with the northern plains of Zhejiang Province showing the lowest diversity (three taxa). The distribution of Actinidia species followed a clear biogeographic gradient, with richness concentrated in the southwest montane regions and declining toward the northeast. Although overall species richness in Zhejiang was relatively modest, the province harbored a disproportionately high number of Chinese endemics, with 11 of the 13 taxa recorded being endemic to China. High interspecific but low intraspecific differentiation was observed across the genus. The floristic composition of Actinidia in Zhejiang was closely related to adjacent provinces including Anhui, Fujian, and Jiangxi. The findings provide a critical foundation for the selection of locally adapted cultivars and the formulation of targeted conservation strategies for Actinidia germplasm in Zhejiang.