Studies On The Physiological Responses To Osmotic Stress And Landscape Application Of Three Wild Sedum Plants

In this study,we use wild Sedum alfredii,S. emarginatum and S.makinoi for materials,and do separately research the physiological Stress response of the three kinds of wild Sedum plants which were on water stress,heat stress and shading stress,and do research about green and organic ecotypes cultivation matrix and landscape application .The results are as follows:⑴With the deepening of water stress,three kinds of Sedum plants'leaf RWC,SP,Pro,MDA were gradual increase(P <0.05),Chla+b and Fv/F0 decreased, POD and CAT activity were first increased and then decreased. Under mild water stress, impact of drought on Sedum by SOD,POD,SP,Fv/F0,Chla+b,RWC,CAT and other indicators is large,and under moderate and severe water stress,the impact of drought on Sedum by SOD,POD,SP,Fv/F0, Chla+b,RWC,CAT and other indicators is large.With membership function value of fuzzy math,we do comprehensive identification of drought resistance for the three kinds of Sedum plants,results as follows:comprehensive identification S.makinoi>S. alfredii>S. emarginatum.⑵At the high temperature of 45℃/30℃day and night, the number of days with heat stress the increase in Chla+b,SOD,PODincreased at first, decreased RWC gradually,increased MDA,H202,Pro,SS. Principal component analysis results showed that the 7 targets of Chla+b,MDA,SS,RWC,Pro,H202,SOD are the main heat-resistant physiological target selection of Sedum . Heat stress order of the three kinds of Sedum plants are S. emarginatum>S. alfredii>S. makinoi.⑶With increasing the degree of shade,the leaves RWC of the three kinds of Sedum plants are increased significantly, LA,MDA,SS,SOD,Chla/b decreased continuously,Chla+b first increased and then decreased. Shade gradient has no significance differences in effects of leaf Chla+b content.Under mild shade stress,the impact of shade tolerance Sedum by LL,RWC,Chla+b,Chla/b,PRO,MDA,SOD is large, under moderate shade stress,the impact of shade tolerance Sedum by LA,LL,SS,Chla/b,PRO,SOD,Chla+b,RWC is large, under severe shade stress,the impact of shade tolerance Sedum byRWC,SS,PRO,SOD,Chla+b和Chla/b is large.⑷The best eco-organic type soilless culture substrate combinations of S. makinoi are A3B1C2 or A2B1C2,that is,(rice husk:wood:slag) as 3:1:2or 2:1:2(volume ratio).⑸Sedum plants'wild resources and landscape application were systemticly studied.