Study Of Photosynthetic Physiological Response Of Bambusa Oldhami Leaves Under Sea Salt Stress

The experiment studies photosynthetic physiological and biochemical mechanisms characteristics ofBambusa oldhami in sea salt stress, using hydroponic method and randomized trial design, in order todiscuss the degree of salt tolerant and salt tolerance mechanism of Bambusa oldhami in the coastalareas. It is studies physical and biochemical response by leaves ultramicrostructure, chlorophyll content,reflectance spectroscopy, fluorescence parameters, photosynthetic parameters, osmotic adjustmentsubstances and membranous protective enzymes of1year old seedlings of Bambusa oldhami in thetreatment of different sea salt concentrations, to reveal that the salt tolerance characteristics andindicators variations of Bambusa oldhami. Results are as follows:(1) high concentrations of sea salt obvious damage the cell structure of the bamboo leaves.Mesophyll cell walls, organelles, chloroplast, nucleus, vacuole are in different degree of damage, thenumber of starch grain and osmium particles on the chloroplast are appeared different variations. It isdamaged in1.2%.(2) with sea salt concentration increases, the chlorophyll contents declined. Chlorophyll a+b notsignificantly decreased in1.2%; chlorophyll a and chlorophyll b has been declining after the stress in1.6%, compared with the control decreased by57.9%and68.7%.(3)the reflectance of the reflectance spectra are different in different sea salt concentrations,mNDVI705、mND705、NDVIgreen、mSR705and Ratio are significantly decreased of1.6%, were decreasedby42.4%,43.9%,32.6%,21.5%and31.1%, respectively.(4) with sea salt concentration increased, Fv/Fm and PIABSfirst increased and then downward,compared to the control, it is not significantly decreased in1.2%. it is significantly decreased in1.6%,decreased by50.8%and92.3%. the ABS/RC is significant increase in1.6%, increased96.9%.(5) photosynthetic rate is decreased by35.0%in1.2%; intercellular CO2concentration is increasedby42.7%in1.2%; stomatal conductance is increased by1.13times in0.4%, and decreased by46.2%in1.2%; WUE are lower30.0%and50.4%than that of the control in1.2%and1.6%respectively.(6) soluble protein content is increased with the increase of sea salt concentration, but decreased in1.6%. Free proline content is increased as the sea salt concentration increased.(7) With the passage of time of sea salt stress, SOD、CAT and POD are increasing, but SOD andPOD are significantly decreased after the four days in1.6%.