To analyze the degree and pattern of phenotypic variation in leaves of Tetracentron sinense Oliv from the perspective of genetic and environmental adaptation and thus contribute to effective evidence-based conservation and management strategies for germplasm resources, we measured 17 morphological and epidermal micromorphological leaf traits from 24 natural populations of T. sinense. Nested analysis of variance, multiple comparison, principal component analysis (PCA), cluster analysis, and correlation analysis were used to explore phenotypic leaf variation among and within populations and potential correlations with geographic and environmental factors. There were significant differences in 17 leaf phenotypic traits among and within populations. The mean phenotypic differentiation coefficient of the 17 traits was 56.34%, and the variation among populations (36.4%) was greater than that within populations (27.2%). The coefficient of variation (CV) of each trait ranged from 4.6 to 23.8%, and the mean was 11.8%. Phenotypic variation of leaves was related to environmental factors such as average annual sunshine hours, average July temperature, and average annual rainfall. The variation changed along gradients of longitude, latitude, and altitude. The PCA clustered the 24 natural populations into four groups. Our study suggests that phenotypic variation in T. sinense occurred primarily among populations, with moderate levels of phenotypic differentiation among populations and low levels of phenotypic variation within populations. The plant’s poor adaptability to the environment is likely an important contributor to its endangerment. Accordingly, conservation strategies are proposed to protect and manage the natural populations of T. sinense.

为了从遗传和环境适应的角度分析中华四叶猴叶片表型变异的程度和模式，从而为有效的基于证据的种质资源保存和管理策略做出贡献，我们从24种植物中测量了17种形态和表皮微形态特征香椿的自然种群。嵌套的方差嵌套分析，多重比较，主成分分析（PCA），聚类分析和相关性分析用于探讨种群之间和种群内表型叶片的变化以及与地理和环境因素的潜在相关性。群体内和群体内的17个叶表型性状存在显着差异。这17个性状的平均表型分化系数为56.34％，群体间的变异（36.4％）大于群体内的变异（27.2％）。每个性状的变异系数（CV）在4.6％至23.8％之间，平均值为11.8％。叶片的表型变化与环境因素有关，例如年平均日照时数，7月平均温度和年均降雨量。变化沿经度梯度变化，纬度和高度。PCA将24个自然种群分为四类。我们的研究表明，表型变异T. sinense主要发生在种群之间，种群之间的表型分化水平中等，而种群内的表型变异水平低。该植物对环境的不良适应性可能是其危害的重要原因。因此，提出了保护策略来保护和管理中华绒螯蟹的自然种群。