Preliminary Research On The Mechanism Of Stipagrostis Pennata Drought And Physiological.

Stipagrostis pennata about 150 species are distributed in temperate and tropical dry regions. China has 11 kinds, xinjiang has 3 kinds, concentration distribution in northern xinjiang GuErBanTongGuTe desert.Stipagrostis pennata floating in half or flow resistance, resistance to sand, sand and wind erosion resistance, is fixed fascinating sand-fixation plants, such as Calligonum leucocladum (Schrenk) Bunge , Haloxylon Persicum Bunge ex Boissplant and other sand plant resistance optimal combination form community. The physiological and biochemical characteristics in its study, not only to find the mechanism of plant resistance adversity, and for stress resistance breeding of plant gene engineering provides theoretical basis.This paper first studied the wild Stipagrostis pennata shape and structure of its special structure root anatomic studies ,in its long-term growth found in the desert environment arid morphological structure, physiological function of anatomical structure and the series of adaptability, and formed a strong drought resistance. Such as leaves, curled up and secretion layer of wax,stem short, formed root set (formed the root of hair epidermal cells, parenchyma cells and epidermal cells and parenchyma cells forming the chamber). Especially the special structure of the formation of root, be helpful for its water retention, and heat insulation, absorb nutrients and so on the function, increase the strength of grasp to sand,steady sand for its desert environment.Using photosynthesis Li6400 tester for Stipagrostis pennata photosynthetic physiology is tested and found that the photosynthetic rate changing the typical single-peak curve, no "break" phenomenon, the peak at 14:00 in 8.9μmol?m-2?S-1, The transpiration rate and stomatal conductance, intercellular CO2 concentration changes are "unimodal" curve.The trend of day change is same. Showing that Stipagrostis pennata still hold high efficiency and adaptability in strong light ray.The temperature outside of mild stomatal conductance influence is bigger. Leaf temperature effection on stomatal conductance is also great influence. Stomatal conductance of instantaneous changes to improve its ability to desert environment.Stipagrostis pennata simulation experimental stress using 10%,20%,30%PEG6000 deal with Stipagrostis pennata during 72 hours, every 12 hours physiological and biochemical detected of change. The results show that with the increasing concentration of PEG, membrane permeability increase and soluble protein significantly increased. Soluble protein and praline are the effective osmoregulation substance in Stipagrostis pennata, but not too proline content basically big changes. MDA rose at first, after that it lower because the body has a protective enzyne function of active.SOD, CAT from stress, they started rising in the early dealed and metaphase stress within the main protection function. In the whole process of stress POD activity always lower than its control leve,showing it is a protection foundation enzyme during the drought stress anaphasis.Through the stacks of various aspects of Stipagrostis pennata observation carefully and found that it is a kind of very good extreme environment genetic resources of drought, use of the characteristics of rare plants, cloned drought directly related genes, reveals the adaptability of the mechanism, and study the genetic basis, to make full use of its potential genetic resources, and the improvement of crop variety, with great academic and economic value.