Studies On The Heat And Chilling Resistance Of Anoectochilus Roxburghii (Wall.) Lindl. Seedling

Anoectochilus roxburghii(wall.)lind,is a rare medicinal herbs and have high enjoy value,but wilding are very exiguous.It's very important to development cultivation.To study on the heat and chilling resistance of A.roxburghii have important significance on survive rate of axenic seedling transplant and success of cultivation.This article taking A.roxburghii axenic seedling as experimental materials to deal with different temperature and time treatment study physiological response of temperature stress and choice feasible temperature hardening. A.roxburghii axenic seedling deal with temperature stress again after temperature hardening and transplant survive,then measure physiological and biochemical indexes.With the aim of providing scientific theory foundation for cultivating of A.roxburghii,the methods of evaluate heat and chilling resistance of temperature hardening seedling are principal component analysis and subordinate function values analysis.Research results shown that heat and chilling resistance physiological and biochemical indexes are all change.The relative of water content in A.roxburghii axenic seedling decreased as the heat and chilling stress proceeded,accompanied by the increasing contents of PMP and MDA, the contents of Chl and Car decreased,osmoticas trend up first and down later.The change of SOD activity is up-down-uo trends,the CAT,APX,POD activity exhibited down-up-down trends after heat sress;SOD activity sustained increase first and then decrease,CAT,APX activity exhibited down-up-down trends and POD activity exhibited down-up trends after chilling stress.The decreasing range of RWC,Chl,Car are all reduce,osmoticas increased,the activitives of protective enzymes increased and sustained at a relatively high level after temperature ardening.Through alalysing results,we have gotten conclusion;1.Trough correlation analyse among the heat and chilling resistance physiological and biochemical indexes of A.roxburghii,the RWC,the content of Chl and Car,PMP,MDA,the content of soluble protein,SOD activity,APX activity are all relation with the changes of most of heat resistance physiological and biochemical indexes,which can serve as heat resistance evaluation indexes.The RWC,the content of Chl and Car,PMP,MDA,CAT activity are all relation with the changes of most of chilling resistance physiological and biochemical indexes,can serve as chilling resistance evaluation indexes.2.Through the principal component analysis and subordinate function values analysis,the results of evaluation on the heat and chilling resistance of A.roxburghii shown that the ability of heat-resistance of four treatments of A.roxburghii seedling on different heat stress;H seedling＞L seedling＞CK seedling＞axenic seedling.The ability of chilling-resistance of four treatments of A.roxburghii seedling on different chilling stress;L seedling＞H seedling＞CK seedling＞axenic seedling,so temperature hardening can increase the heat and chilling resistance of A.roxburghii,heat hardening of 28℃,2 days and chilling hardening of 8℃,4 days are both effective,which can provide direction for cultivating of A.roxburghii.3.The temperature hardening have cross adaption,but the effect of heat hardening to enhance A.roxburghii heat resistance is better than chilling hardening,the effect of chilling hardening to enhance A.roxburghii chilling resistance is better than heat hardening,maybe the mechanisms of increasing heat and chilling resistance of two kind of temperature hardening have commonness and peculiarity,which will wait more research.