【目的】利用同质园法,探究油桐叶片结构对地理环境变化的响应与适应规律。【方法】采用常规石蜡切片法、指甲油印迹法,对46份油桐种质资源叶片解剖结构及气孔特征进行观察测量,结合冗余分析、传统相关分析和系统聚类等方法,研究油桐叶片结构性状的差异及其与环境因子的关系。【结果】油桐种质之间叶片结构特征变异系数较大且存在极显著差异(P<0.01),尤其是栅海比、气孔面积、气孔密度、海绵组织厚度的变异超过20%,叶片解剖结构之间、叶片气孔结构之间分别存在不同程度的相关性。影响油桐叶片结构性状变异的主要地理环境因子为纬度、经度、年均温、年均降水量。主成分分析结果显示,前5个主成分的累积贡献率达91.02%;选取气孔密度、气孔周长、气孔面积等10个叶片性状进行系统聚类,将46份油桐种质资源在欧氏距离5.0处划分为3个类群,聚类结果反映出各个类群中叶片的结构特征,差异主要体现在叶片气孔特征方面。【结论】地理环境的差异是影响油桐叶片结构变异的重要因素。

【Objective】A common garden experiment was used to explore the adaptation mechanisms of leaf structure to geographical environment changes. 【Method】In this study, the anatomical structure and stomatal characteristics of the leaves of 46 Vernicia fordii provenances were observed and measured by the paraffin wax slices method and nail oil seal method. Redundancy analysis, traditional correlation analysis and systematic clustering were used to analyze the differences in leaf structural characteristics, as well as the relationship between leaf traits and environmental factors.【Result】The results showed that the leaf structure characteristics of V. fordii had significant variation (P<0.01), the coefficients of variation of P/S, stomatal area, stomatal density and spongy tissue thickness were more than 20%. There were significant correlations between the leaf anatomical structure and leaf stomatal structure. Latitude, longitude, mean annual temperature and mean annual precipitation contributed largely to the variations of leaf structure characteristics of V. fordii. Principal component analysis revealed that the first five principal components represented 91.02%. Ten indexes, including stomatal density, stomatal perimeter and stomatal area, were selected for hierarchical cluster analysis. Overall, 46 V. fordii germplasms were clustered into three groups with a Euclidean distance of 5.0. The clustering results reflected the characteristics of the leaf tissue structure of various groups, and the difference was mainly reflected in the stomatal characteristics. 【Conclusion】 The difference in the geographical environment was one of the major factors that affected the variations of the leaf structure of V. fordii.