Comparative Studies On Photosynthesis Of Two Desert Ephemeral Plants Eremurus Inderiensis (M.Bieb) Regel And E.anisopterus (Kar.et Kir) Regel

Many indexes such as photosynthetic pathway,chlorophyll content,stoma size and density,SLA (specific leaf area),biomass,Pn,E,Gs,Ci,WUE and chlorophyll fluorescence characteristics of Eremurus inderiensis (M.Bieb) Regel and E. anisopterus (Kar. et Kir) Regel were comparatively studied, which wildly grow in Gurbantunggut Desert in Xinjiang. Futhermore, we discussed the unused mechanism of nutriment of E. inderiensis and E. anisopterus. The main results showed:1.The leaf structure of E. inderiensis and E. anisopterus show that they are all more special and complex than other endogens. There are palisade tissue in leaf, and alternate with big and small veins closing to palisade tissue, which can affect the photosynthesis of E. inderiensis and E. anisopterus. The sheath of small vein are like wreath. The thickness of palisade tissue indicate that the photosynthesis ability of E. anisopterus is higher than E. inderiensis.2.Theδ13C values of E. inderiensis and E. anisopterus at seedling and flowering stages separately are -29.17‰and -26.74‰, -27.03‰and -26.77‰. According toδ13C value and their anatomization characteristics, they are all belong to C3-C4 intermediate plants.3.We determine Chlorophyll content and stoma size,density of E. inderiensis and E. anisopterus leaf with Acetone-Pick-up and Laminae-eduction methods. Results indicate that they have big stoma size but small density and E. inderiensis has lower chlorophyll content and stoma density than E. anisopterus, which indicate that they have high photosynthesis and low evaporation, E. anisopterus has bigger potential.4.E. inderiensis has little different at height and is lower at biomass, higher at SLA than E. anisopterus, which indicate that E. anisopterus has higher carnification extent and big possibility of higher photosynthesis efficency under enough water condition.5.Under natural condition, the portable photosynthesis system of Li-6400 was used for the dynamic research of photosynthesis of E. inderiensis and E. anisopterus at seedling,flowering and seeding stages, and then we get the diurnal change curves of photosynthesis of every stage and A-light curves. Results indicate that the diurnal changes of net photosynthetic rate of E. inderiensis and E. anisopterus displayed single-peak pattern at seedling stage and two-peak pattern and seeding stage and two pattern at flowering stage. The significant difference between A-light curves of E. inderiensis and E.anisopterus and typical desert plants show that they are all high light saturation point,low light compensation point and strong respiration as C3-C4 intermediate plants, which indict their special way for adaptation to desert habitat.6.During the time of measuring photosynthesis of E. inderiensis and E. anisopterus, the portable chlorophyll fluorescence system of OS5-FL, which is made in USA, were used to measure diurnal changes of chlorophyll fluorescence of E. inderiensis and E. anisopterus at the same time. Results show that diurnal average of Fv/F0,Fv/Fm,Y,ETR,qN,qP values of E. inderiensis are lower than E. anisopterus, but Fv'/Fm'value of E. inderiensis is higher than that of E. anisopterus at seedling stage. All diurnal average of chlorophyll fluorescence indexes of E. inderiensis are bigger than E. anisopterus expect qN value at flowering stage.