Effect Of Calcium Ions In The Process Of Responses Of Phyllastachys Edulis Seedlings To Drought

In order to investigate the changes of Ca²⁺distribution and concentration in Moso bamboo（Phyllostachys edulis） roots and the effect of calcium signal on the physiological mechanism ofPhyllostachys edulis in drought condition, the seedlings was been studied respectively by fluorescentstaining and measuring some physiological index after treated by different reagents（EGTA、LaCl3、heparin、CPZ、caffeine�'�CaCl2）. Which ware very important for clarifying the mechanism of calciumsignal controlling the response of Phyllostachys edulis to drought. The main conclusions were drawn asfollows:1. Ca²⁺distributed in the whole root in drought condition. However, the concentration of Ca²⁺inmeristem was less than in other parts. As the stress increased, Ca²⁺in the cell walls wouldgradually release to cytoplasm. Ca²⁺was evenly distributed in cytoplasm when treated by20%PEG solution. It was indicated that Ca²⁺participated in the respond of Phyllostachys edulis todrought.2. The concentration of Ca²⁺in the root was highest when treated in drought condition about15minutes, then, declined. With the stress increased, the concentration of Ca²⁺in the root rose. Whichwere higher in20%PEG solution than other different concentration PEG solutions in allmeasurement times.3. It was suggested that Ca²⁺can alleviate the membrane injury of Phyllostachys edulis resulted bydrought through comparing the effect of different reagents on conductivity, MDA and H2O2content.4. After measuring the activities of protective enzymes, soluble protein and chlorophyll content ofleaves, it was concluded that calcium signal could improve drought resistance of Phyllostachysedulis maybe by regulating the activity of protective enzymes, and calcium messenger involved inthe signaling process of soluble protein expression and the biosynthesis of chlorophyll.5. Proline content could be used as important index to measure the damaging extent of Phyllostachysedulis under drought stress.6. Calcium signal involved in the response of Phyllostachys edulis to drought through severaldifferent pathways.