欧李叶表皮形态气孔指标与叶果矿质元素含量变化的关系

欧李(Cerasus humilis)是我国特有的一种野生果树资源,其果实中钙、铁等元素尤为丰富(曹琴等,1999),同时具有抗旱、耐寒、耐贫瘠、耐盐碱等特性,是生态建设和防风固沙的良好树种(姜英淑等,2009;李学强等,2009).研究表明:叶片是植物进化过程中对环境变化敏感且可塑性较大的器官,叶表皮形态结构随着环境的变化而形成自身相对稳定的遗传特征,叶片的气孔、表皮毛、角质层等结构与植物的抗逆性密切相关(李芳兰等,2005;李正理,1981;Bosabalidis et al.,2002;Sam et al.,2000;Mendes et al.,2001),而叶片气孔形态指标大小变化影响着植物的蒸腾、光合、呼吸等作用(潘瑞炽,2008).

Relationship between Leaf Epidermal Micro-Morphology and Stomata Indices and Mineral Elements Content Variations in Leaves and Fruits of Cerasus humilis

Seedlings of Cerasus humilis of collected from the Yanshan Mountains were used as materials,and the leaf epidermal cells and stomata micro-morphology characteristics were studied by a Scanning Electron Microscope.Variations of mineral elements in leaves and fruits and their correlations with leaf epidermal micro-morphology characteristics were also investigated to reveal the absorption and accumulation mechanism of mineral nutrients in C.humilis.The results showed that the upper and lower epidermal cells could be divided into two types,one type was concave and connected like a honeycomb and the other type was ridgy and nearly round.The upper epidermal cells were covered with striated cutin.There were some epidermal trichomes but no stomata on the upper epidermis,and stomata only distributed on the lower epidermis.The stomata extruded from epidermal cells with irregular shapes.The average length,width,size and density of stomata were(8.17±1.37)μm,(2.60±0.68)μm,(21.99±9.17)μm2 and(867.43±198.65)mm-2 respectively.There were significant differences in the leaf epidermal micro-morphology,the stomata length,the stomata width,the stomata size,the stomata density,and the content of mineral elements in leaves and fruits over different lines.Correlation analysis showed that there were significant positive linear relationships between the content of Ca and Mg in leaves and the stomata width and stomata size.The Ca and Zn content in fruit were significantly positively correlated with stomata width but significantly negatively correlated with stomata length.The Na content in fruits was significantly positively correlated with stomata density.No significant correlation existed among other elements content in leaves and fruits and stomata morphological indices.The study indicated that mineral elements absorption and accumulation in C.humilis leaves and fruits could be characterized by the leaf epidermal stomata morphological indices.