Study On Drought Resistance Of Wild Centipedegrass

Ya'an centipedegrass cultivated in the pot or in the water was used as material to study its drought resistance in this experhnent.The changes of the plants' morphologies and physiologies were studied under drought-stress. The purpose of this experiment is to find theoretical foundation for centipedegrass'exploitation and use. The result showed:l.In pot culture experiment centipedegrass still grew at certain drought-stress.There was not much difference between control and treatment in the frist growing period. Along with the process of water-stress the length and width of treatment became shorter and narrower than control. On the fifteenth day of drought-stress a small part of leaves became foldable. The length of leaf was 7.04 cm and width of leaf was 4.40cm on the fifteenth day of drought-stress when the content of soil water was 1.02%. The length of leaves decreased 0.78cm and the width of leaves decreased 0.52mm compared with control on the fifteenth day. The length of root became longer than control and the number of root increased under drought-stress. On the fifteenth day of drought-stress the length of root was 16.30cm and the number of root was 16.The length of roots increased l.lcm and the number of roots increased 3 compared than control. The experiment showed the length and width of the leaves and the length and number of the roots changed obviously (PO.05).The result of physiologies showed: Under drought-stress chlorophyll decomposed. On the zero day the content of chlorophyll was 1.304 mg/g.FW . On the twentieth day the content of chlorophyll was0.84mg/g.FW.On the twentieth day the content of soluble carbohydrate relative electric conductivity and MDA increased and the content of these three physiologies increased sharply. The increase extent of this three physiologies were 30.71?cK 101.31? 20% and the material was stressed for 24 hour and 48hour. Both morphologies and physiologies of the part of centipedegrass which grew above soil had the same trend compared with pot culture experiment. The color of root became darker than control after and some roots withered after being stressed. Root vigor was increased after being stressed by PEG(5% and 10%) for 24 hour. The increase extent was 11.7% and 18.9% compared with control.Root vigor decreased after being stressed by PEG(20%) for 24 hour and all consistencies for 48 hour.3.Both pot culture and water culture showed the mechanism of drought resistance of centipedegrass are drought tolerance and drought escape.4. Since the operations of the experiment for MDA chlorophyll and relative electric conductivity are easy and these three indexes have significant correlation to the content of soil water in pot culture and these three indexes have significant correlation in twos both in pot culture and water culture they can be used for drought resistance indexes.