Studies On Influencing Factors Of Cutting Roots And High Efficiency Seedling Raising Techniques Of Xanthoceras Sorbifolium Bunge

As a kind of excellent tree species which integrates greening,ornamental,edible and medicinal,Xanthoceras sorbifolium Bunge has high development value.In order to realize the base,seed,scale cultivation,popularization and application of new varieties,and provide a large number of fine varieties and high quality strong seedlings,but the method of sexual propagation can not maintain the excellent characters of stock plant.It is necessary to reveal the restrictive factors of asexual propagation of Xanthoceras sorbifolium Bunge and solve the technical difficulties of large-scale asexual propagation.Therefore,through reference and application of cutting and histication technology system,this study reveals the restriction factors and mechanism of root cutting and tissue culture seedling forming,and explores the technical measures to improve the success of asexual reproduction effectively,and provides the basis for constructing the asexual rapid propagation technology system.The results of this experiment are as follows:1.In order to realize the hard branch cutting propagation of Xanthoceras sorbifolium Bunge successfully,it is necessary to effectively integrate the treatment techniques of the following key links:(1)The overwintering treatment of cellar sand storage is the best way to promote the survival rate of hard branch cutting of Xanthoceras sorbifolium Bunge.The cutting root effect and the growth of cutting seedlings are the best,and the survival rate of cutting is 38.33%;(2)The optimum medium for hard branch cutting of Xanthoceras sorbifolium Bunge is peat + perlite(7:3),Second,coarse sand + peat +perlite(1:7:2);(3)The length range is 9~11 cm and the thickness range is 0.6~0.8 cm are the optimum specifications of cutting seedling for hard branch cutting of Xanthoceras sorbifolium Bunge hard branch cutting seedling,and its root growth is good.2.In order to realize the hard branch cutting propagation of Xanthoceras sorbifolium Bunge successfully,it is necessary to effectively integrate the treatment techniques of the following key links:(1)The effect of low concentration ABT-1 soaking treatment was better than that of high concentration ABT-1quick diping treatment,and the survival rate of cuttings soaked in ABT-1 200 mg·L-1 for 2 h was the highest(46.67%),it was significantly higher than that of hard branch cutting of Xanthoceras sorbifoliumBunge(38.33%);(2)By regularly measuring the changing trend of nutrient content and enzyme activity in the process of cutting root,it was found that the change range of the substance in hormone treatment was larger than that in the control treatment.,the phloem of cuttings through soaking in ABT-1 200 mg·L-1 for 2h changed most obviously,the accumulation of soluble protein,the transformation of soluble sugar and the decomposition of starch were significant,and the total nitrogen was also higher;The activity of POD,PPO,SOD increased first and then decreased,and when the root primordium was induced and formed,the activities of these three enzymes increased to the peak,which was beneficial to the formation of adventitious roots.However,the activity of IAAO showed a low level except for the temporary increase during the time that adventitious root were inducted,which indicated that low activity IAAO could promote the cuttage of Xanthoceras sorbifolium Bunge.The C/N value is also higher than that of the other two treatments,which indicates that the high value of C/N can promote the formation and extension of adventitious roots.3.The best way to succeed in tissue culture of Xanthoceras sorbifolium Bunge is stem segment with buds culture and need to grasp the following key technical links:(1)The best explants selected for tissue culture of stem segments of Xanthoceras sorbifolium Bunge were axillary buds,and the induction rate of axillary buds was significantly higher than that of bud tips;0.1% Hg Cl2 is used as bactericidal agent,and the optimum sterilization time is 9 min;MS is the best basic medium for axillary bud induction;The optimum concentration of activated carbon was 0.75 mg·L-1;The axillary bud induction rate is the best when the medium adds 2.0 mg·L-1 6-BA and 0.1 mg·L-1 NAA,and the bud seedlings grow strongly;(2)When the MS medium adds 0.5 mg·L-1 6-BA and 0.1 mg·L-1 NAA,the effect of bud proliferation and differentiation is the best.