Leaf Anatomical Structure and Drought Resistance of Typical Drought-Tolerant Plants in the Dry-Hot Valley of Yuanjiang River

With the 22 typical xerophytic species leaves in the dry-hot valleys of Yuanjiang River as test materials, to find its similarities and differences in the adaptation strategies of arid and hot environment and screen out excellent ecological restoration plants, using conventional paraffin section technique and optical microscopy technique to analyze the differences in leaf anatomy. And the tested plants were clustered by anatomical quantitative traits, transformation traits and multivariate traits. The results indicated that the adaptability to arid and hot environmental showed a diversity in leave structure. All the leaves of the tested tree species had obvious characteristics of xerophyte. The leaves were divided into isobilateral or bifacial leaves according to the differentiation of spongy tissues, among which the bifacial leaves plants were the majority, which were 13 kinds; there are 9 species of isobilateral leaves plants. The anatomical structure of the tested plants differs greatly, reflecting the evolutionary results of the plant's long-term adaptation to arid and hot environment. The results of cluster analysis show that the difference is mainly based on the thickness of sponge tissue, the thickness of palisade tissue and the diameter of main vein. The plants are divided into 5 categories, which mainly reflect the differences in the degree of development of the tested plants in aerated tissues, transport tissues and assimilated tissues.