Preliminary Study On Cutting And Tissue Culture Propagation Technology Of Pterocarya Stenoptera

Pterocarya stenoptera is a deciduous tree belonging to the juglandaceae family.It is mainly distributed in the Yangtze river and Huaihe river basin.Its broad crown and developed root system not only have ornamental value,but also can prevent soil erosion;bark and leaves can be used as medicine;wood can be used as furniture.This paper uses Pterocarya stenoptera as research material to conduct preliminary research on cutting propagation and tissue culture techniques.The research results can provide theoretical basis for cutting propagation and provide references for further research on tissue culture techniques.It has certain application value.The main results are as follows:（1）Hard cutting and soft cutting of Pterocarya stenoptera belong to rooting type of bark.（2）The rooting process,cutting survival rate and root growth of hard cuttings were significantly affected by the type of substrate,the size of the cuttings（diameter,length and position of the cuttings）and root-promoting agent（type and concentration）.The rooting rate of hardwood with mixed matrix of peat soil and perlite was the highest（93.9%）.Rooting is best when the base of the seedling is used as cuttings.Cuttings with a thickness of 7.5～10.5 cm and a length of 10.0～15.0 cm had better rooting effect.IBA treated cuttings with a mass concentration of 150 mg·L^-11 had the best rooting effect for 2 h,After 78 days,the rooting rate reaching 88.4%,the root effect index reaching 9.94,the seedling height of 26.78 cm and the ground diameter of3.94 mm.（3）The root promoter GGR 2000 mg·L^-11 was used for cuttings,and the roots were dipped for 20～30 s（other conditions were the same as for hardwood cuttings）,and the growth effect was the best.After 60 days,the root effect index was 2.87,the seedling height was 3.13 cm,and the ground diameter was 2.10 mm.（4）During the rooting process of hardwood,the protein content at the base of cuttings showed a trend of decreasing,increasing,decreasing and increasing,and the soluble sugar content showed a trend of decreasing,increasing and decreasing.Endogenous hormone GA3showed a trend of up-down,ABA up–down-up,IAA down-up-down,while ZR showed no obvious change trend.The IAA/ABA value showed a trend of decreasing-increasing-decreasing,and the IAA/ZR value showed a trend of decreasing-increasing-decreasing-increasing.During the rooting process of cuttings of soft wood,the soluble sugar content first decreased sharply and then increased slowly,while the protein content generally decreased and increased.（5）The application of root promoters can promote the utilization of soluble protein and soluble sugar,increase the content of GA₃,ABA,IAA and ZR,increase the values of IAA/ABA and IAA/ZR,and promote the rooting of cuttings.IBA had the most obvious effect on these substances,followed by ABT.The change trend of nutrients and endogenous hormones corresponds to the induction and occurrence stage of adventitious roots in cuttings,which reflects the consistency of physiological changes and morphological changes.（6）In the Pterocarya stenoptera tissue culture seedling experiment,Semi-lignified young stem segments with axillary buds as materials,disinfection with 75%alcohol 30s and 0.1%HgCl₂ for 8～10min,MS+1.0 mg·L^-11 6-BA+0.1 mg·L^-11 IBA as adventitious bud induction medium,MS+1.0 mg·L^-11 6-BA+0.1 mg·L^-11 KT as bud proliferation medium,MS+0.2 mg·L^-16-BA+0.5 mg·L^-11 NAA as callus proliferation medium,1/2MS+0.5 mg L^-11 NAA was used as root induction medium had the best effect.