Phenotypic Plasticity And Anatomical Characteristics Responses Of Five Plants To Different Altitudes Of Yulong Mountain

The global climate changes have influenced the growth and distribution of plants, and the ability of plants adapted to the changing environment becomes the concern of the current biologists. Herbaceous plants showed strong adaptability to disturbance, because of its relatively short life cycle, widely distributed areas. These plants played important roles in maintaining ecosystem function. In this study, five perennial herb plants, namely Polygonum paleaceum, Rhodiola bupleuroides, Epilobium amurense, Pedicularis gruina and Potentilla fulgens, which distribute widely in wide altitudes of Yulong Mountains, were selected as the study object. The relationship between phenotypic features, reproductive allocation, leaf anatomical structure and the altitude were studied. The aim is to discover how the plant phenotype and the anatomical structure adapt to altitude, thus discloses plant adaptation to the environment changes. The main results are as follows:1. Phenotypic characteristics analysis showed plant height, leaf length, leaf width of all five species decreased with the rising of altitude (P<0.05). In which, plant height, leaf length, leaf width of P. paleaceum decreased sharpest, and the values of decreasing ratio were 83.03%,84.64%,74.87%, respectively. It illustrated the P. paleaceum has the greatest phenotypic plasticity.2. Biomass analysis shows, five species vegetative organs of biomass decrease as altitudes rising (P<0.05). Among them the total biomass of P. paleaceum and E. amurense of vegetative organs of biomass are significantly negative correlation between the altitudes (P<0.01). Five species plant reproductive allocation ratio increased with altitude. In which, P. gruina and E. amurense reproductive allocation proportion with the altitude are significantly positive correlation (P<0.01). While the reproductive allocation proportion and size are significantly negative correlation between relationship of the P. gruina and E. amurense (P<0.05). It shows that the smaller plants are, the greater the reproductive allocation proportions are.3. Microscopic anatomy shows that P. paleaceum, E. amurense, P. gruina and P. fulgens are the leaves in different planes mainly consists of epidermis, mesophyll and main vein. Among them, the P. paleaceum main vein have a number of vascular bundles, and the vascular bundles in the main vein of form a circle of discontinuous loop structure, the rest of the four plants main vein there is only one big vascular bundles. R. bupleuroides blade microstructure shows that it is a typical surface of leaf, mesophyll part no obvious palisade tissue and spongy tissue differentiation. Five species of plant stomata are distributed in epidermis, mostly oval or suborbicular, southwest Withers ling food skin have long table, leaf epidermal cells are under a random type, the anticlinal wall of a skin style has two kinds of bow and wavy.4. The organizational structure of determination shows that five species plants on the epidermis and lower epidermis thickness, palisade tissue thickness, leaf thickness and the thickness of the main vein of thickening trend with the increase of altitude, and P. gruina on the epidermis and lower epidermis thickness, palisade tissue thickness, leaf thickness increase in five kinds of plants are the largest, reaching respectively 80.36%,267.16%,175.56%,205.51%. The main vein thickness of P. paleaceum increase the largest156.46%, the smallest increase the thickness of surface is 11.07%; R. bupleuroides under the main vein thickness, epidermis thickness are the smallest increase, Respectively 50.60%,5.16%; E. amurense leaf thickness, palisade tissue thickness increase are minimal, respectively 13.22%,16.54%; P. gruina the largest rise in sponge tissue thickness 348.38%, P. paleaceum the spongy tissue thickness increases to a minimum 47.39%. E. amurense the spongy tissue decreases with the increase of altitude, drop of 53.93%. Thickness of palisade tissue to that of spongy tissue, lightness of leaf palisade tissue structure, looseness of leaf sponge tissue structure along with the change of altitude increases has little change of bifacial leaf. Five species plant phenotype and blade microstructure is mainly to reduce transpiration, increase the development of water-based and improve photosynthetic efficiency from three aspects, prominent reflects its shape by the ecological environment in the process of evolution and genetic characteristics of preserved.5. Analysis shows that the porosity change with increasing altitude, stomata density significantly increased of P. paleaceum, R. bupleuroides, E. amurense, P. gruina, P. fulgens (P<0.05). Stomatal length and the altitude have significant negative correlation of P. paleaceum, R. bupleuroides, E. amurense (P<0.05). Stomata width and altitude were significantly negative correlation of P. paleaceum, E. amurense, P. fulgens (P<0.05). Stomata length of all five plants positively correlated with width of stomatal, stomata density and stomata length and negatively correlated with stomata width.