Study On Cold Resistance Of Four Sedum Plants

The four kinds of market potential sedum,Sedum lineare,Sedum spurium'Coccineum',Sedum emarginatum,Sedum polytrichoides were used as as materials in the paper.In this paper,they were studied by main component analysis,variance analysis and subordinate function values analysis.The cold resistance characteristics of sedum was systematically investigated from physiology and biochemistry,based on cold resistance system,aims to study the cold resistance characteristics and mechanism.And compare their characteristics of cold resistance,and provide evidences to and promote their applications.The major results were summarized as follows:1.As the temperature decreased, relative electric conductivity of leaves had a gradually increased while total chlorophyll had a gradual decrease.SOD activities declined at first,then raised and at last declined.Soluble protein content declined at first,then raised and at last declined.MDA content had a gradual upward trend.Proline content had a gradual upward trend under freezing resistances and during the overwintering.2.The changes of physiological and biochemical indicators on four sedum plants were basically same under freezing resistances.The relative electric conductivity of Sedum spurium'Coccineum'was the lowest,its total chlorophyll,SOD activities,MDA content,proline content were the highest,its soluble protein content were middle level.The result of physiological and biochemical indicators of Sedum lineare and Sedum emarginatum was closer,their relative electric conductivity were the highest,their total chlorophyll,MDA content were the lowest,their SOD activities,proline content were middle level.However,large differences between the soluble protein content,Sedum lineare was the highest,Sedum emarginatum was the lowest.The relative electric conductivity,total chlorophyll,soluble protein content of Sedum polytrichoides were middle level,their SOD activities,proline content were the lowest.3.After recovery growth,relative electric conductivity,from higher to lower,was Sedum emarginatum>Sedum lineare>Sedum polytrichoides>Sedum spurium'Coccineum'.Total chlorophyll,from higher to lower,was Sedum polytrichoides>Sedum spurium'Coccineum'> Sedum emarginatum>Sedum lineare.SOD activities,from higher to lower,was Sedum lineare> Sedum emarginatum > Sedum polytrichoides > Sedum spurium'Coccineum'.Soluble protein content,from higher to lower,was Sedum lineare>Sedum emarginatum>Sedum spurium'Coccineum'>Sedum polytrichoides.MDA content,from higher to lower,was Sedum lineare>Sedum emarginatum>Sedum spurium'Coccineum'>Sedum polytrichoides. Proline content,from higher to lower,was Sedum spurium'Coccineum'>Sedum lineare >Sedum emarginatum>Sedum polytrichoides.4.The changes of physiological and biochemical indicators on four sedum plants were basically the same during the overwintering period.There was a negative correlation between the electrolyte leakage and the cold resistance of sedum,while there was a positive correlation between chlorophyll content,SOD activities,soluble protein content,proline content and the cold resistance of sedum.5.The relationship between relative electric conductivity,total Chlorophyll,MDA content and the cold-resistance ability of sedum was closer by component analysis.6.The cold-resistance ability of four sedum plants,from higher to lower,was Sedum spurium'Coccineum'>Sedum polytrichoides>Sedum lineare>Sedum emarginatum,by subordinate function values analysis.