The Growth And Physiological Responses To Drought Stress And Comprehensive Evaluation Of Drought Resistance Of Stenotaphrum Secundaum And Eremochloa Ophiuroides

Augustinegrass (Stenotaphrum secundatu) and Centipedegrass (Eremochloa ophiuroides)belong to warm-season turf grasses of C₄～plant, widely distributed in south of China. However,the study of Augustinegrass and Centipedegrass have been documented few to take good use oftheir excellent characteristics, such as drought resistance, shade tolerance, pollution controlability etc., which make the two turf grasses an important role in turf industry. Consequently,the further study, especially the research of stress resistance is very important for the further useof Augustinegrass and Centipedegrass.Four ecotypes of Augustinegrass (Miyazaki and Jurong) and Centipedegrass (Deyangand Nanjing) were designed to determine the differences of growth, physiologicalresponses and drought resistance ability among ecotypes under greenhouse drought stressand field water deficit.Under greenhouse drought stress, the growth rate, extending range, dry biomass,branches of single stolon and leaf length were obviously declined. Drought stress alsodecreased leaf water content, whole chloraphyIl concentration and CAT activity. However,leaf SOD activity, POD activity and MDA content increased with drought stress.Under field continuous drought stress, growth rate, branches of stolon, leaf lengthobviously declined, nevertheless, leaf water content increased and MDA content decreasedsignificantly during field water deficit. SOD activity of the four turf grasses increased at thebeginning of water deficit and then decreased with drought stress. POD activity ofAugustinegrass increased rapidly and then kept stable with water deficit, however, PODactivity of Centipedegrass changed indistinctively. CAT of the four turf grasses descendedat the beginning of water deficit and then remained stable with field water deficit.The results of comprehensive evaluation of subordinate function value showed thatthere were differences between greenhouse experiment and field experiment. And thedrought resistance were Miyazaki＞Deyang＞Jurong＞Nanjing under greenhouse drought stress; however, Miyazaki＞Jurong＞Deyang＞Nanjing under field continuous waterdeficit.