Studies On Ectomycorrhizae Fungi Inoculation Making Technology And Mechanism Of Bud Seedling Graft Survival Of Castanea Mollissima Bl

Chinese chestnut(Castanea mollissima Bl.) is a famous fruit tree with good economic and ecological value.In order to to raise mycorrhizal infection rate and chestnut bud seedling graft survival rate,this paper studied the making technology of mycorrhiza fungi inoculations and the mechanism of bud grafting survival in the greenhouse of Beijing Forestry Univeisity.This paper selected the best mycoeehizal fungi by infecting effection experiments,and also studied the making technology of mycorrhiza fungi inoculations.Based on grafting seedlings infecting experiments,this paper found the right time for mycorrhiza fungi infecting.At the same time,this papeir studied the physiological and biochemical basis of bud seedling graft survival by detemined different Physiological and biochemical indexes of scions and stocks before grafting.With "X" light analysis and determination of the changes of plant hormones and enzyme activity of the interface,this paper revealed the healing mechanism of Chinese chestnut bud seedling grafting.The results were as follows:(1) The new mycorrhiza fungi B and D could infect the root of Chinese chestnut very well,could be used in the mycorrhiza chestnut seedling cultivations.In the process of inoculations preparation, tempreture,inoculum concentration and stromata could affect the vigor of inoculations greatly.In the process of medium dishes cultivation,the best cultivation temperature of mycorrhiza fungi X.c and B was 28℃while the best cultivation temperature of mycorrhiza fungi C.s and D was 25℃.In the process of liquid inoculation cultivation,the best proper inoculum concentration of mycorrhiza fungi X.c,B and D was 15/25ml while the best proper inoculum concentration of mycorrhiza fungi C.s was 10/25ml.In the process of solid inoculation cultivation,the best cultivation temperature of mycorrhiza fungi X,c,C.s,D and B were 25℃.The best proper inoculum concentration of mycorrhiza fungi C.s,Band D were 25ml/100g stromata while the best proper inoculum concentration of mycorrhiza fungi X.c was 50ml/100g stromata.All these four mycorrhiza fungi prepared to grow well on the stromata of 85%turfy soil and 15%cornmeal.(2) The best infection time was in 1-2weeks after Chinese chestnut bud seedling grafting.The infection of bud seedling stocks had no effect on Chinese chestnut bud seedling graft survival rates (3) Physiological and biochemical basis of scions and stocks had close relation to Chinese chestnut bud seedling graft survival.The contents of soluble sugar,starch,soluble protain and ratio of total C/N of scions were positive related to the graft survival.The contents of total N and polyphenol of scions were negative related to the graft survival.The contents of soluble protain and polyphenol of bud seedling stocks were negative related to the graft survival.The contents of IAA and ZT of scions are positive related to the graft survival,while the contents of ABA of scions are negative related to the graft survival.The contents of GA₃ of scions almost have no relation to the graft survival.When the IAA/ABA rate is higher than 2.5 and the moisture content of scions is higher than 45%,the graft survival rate is higher than 90%.Higher PPO activity and lower PAL activity of scions favor gaft survival.The contents of IAA,GA₃ and ABA,and the ratio of IAA/ABA of bud seedling stocks were positive related to graft survival,while the content of ZT of bud seedling stocks had no relation to graft survival.Higer PPO activity and medium PAL activity of bud seedling stocks favor graft survival.(4) The first 6days after grafting was isolation-layer stage,PPO enzymatic activity was increasing,and the endogenous phytohormones level was not high.6-12days after grafting was callus formation stage,the IAA,ZT levels were increasing,and the IAA played a leading role in this period.12-18d ays after grafting was callus differentiation stage,the IAA level decreased first,and then increased. IAA was in a lower level in this stage.ZT level increased first,and then decreased.ZT was in higher levels in this stage.PAL enzyme activity was higher in this stage,promoting vascular cells differentiation,promoting the connection between the scions and stocks.18days after graft,the healing process overed and the endogenous phytohormones level decreased.