Evaluation And Selection Of Excellent Single Plant Clones From Hybrid Progenies Of Eucommia Ulmoides Varieties

Eucommia ulmoides is a unique economic tree species in China,which has important research value and economic value.It has been planted in 27 provinces and autonomous regions of China,with an area of 350000 hectares.But at present,the cultivation rate of Eucommia ulmoides is not high,which can not meet the needs of the development and utilization of Eucommia ulmoides resources.On the basis of factorial mating design and hybridization,excellent single plant selection and clonalization of Eucommia ulmoides species in the early stage,the field comparative tests were carried out in Yangling and Lueyang of Shaanxi Province,respectively.The drought resistance,growth character,medicinal component content and Eucommia ulmoides gum content of the clones and their parents(control)were determined and analyzed,and a batch of excellent clones were preliminarily selected The breeding of new varieties of Eucommia ulmoides laid the foundation.The main results are as follows:(1)There were significant differences in tree height,breast height diameter,total leaf number,leaf area,leaf length,leaf width and leaf dry weight between the two sites.In yangling experimental site,total leaf number,leaf area,leaf dry weight and tree height's coefficient of variation of growth character is large.Leaf dry weight,leaf area,total leaf number,leaf width's coefficient of variation of growth character is large in Lueyang experimental site.The coefficient of variation of clonal growth characters in Yangling experimental site was larger.The height,total leaf number,leaf thickness and dry weight of the leaves were significantly different in the interaction level between the site and the clone,and the leaf width was significantly different in the interaction level between the site and the clone.Seven fast-growing and high-yield clones were selected according to tree height,breast height diameter,total leaf number and dry weight of leaves,tree height,breast diameter,total leaf number,leaf dry weight traits exceeded the average of the control group.(2)In the two test points,there were significant differences in 13 leaf anatomical characters such as main vein thickness,palisade tissue thickness,sponge tissue thickness,CTR,SR between clones.In Yangling experimental site,vascular bundle,main vein,pachynchyma,palisade cell and leaf thickness' s variation coefficient of leaf anatomical characters is large.Vascular bundle,lower epidermal cells,palisade cell,P/S's variationcoefficient of leaf anatomical characters is large in lueyang experimental site.There were significant differences in the interaction level between clones and sites.Combined with the membership function values of each character in the two test points,5 clones with good leaf anatomical structure were selected,the main vein thickness,thick corner tissue thickness,leaf thickness,and palisade tissue thickness all exceeded the average value of the control group.(3)There were significant differences in ??0,??100,?max,RWC0,VP/V0 among clones.The coefficient of variationvalues of ?max,??0,??100 are large.According to the average value of the membership function of each index of the clone,5 clones were selected,??0and ??100 exceeded the average of the control group.(4)5 clones with strong drought resistance were selected according to average value of the criteria of the total value of leaf anatomical structure membership function,the total value of water parameter membership function in Yangling experimental point and the leaf anatomical structure membership function of clones in Lueyang experimental point,all of which exceeded the average value of the control group.(5)There was a significant difference in Eucommia ulmoides gum content among clones,and the coefficient of variation was 17.61%.Three clones with higher gum content were selected,which was 41.37% higher than the average value of the control group.(6)In the two test points,the content of rutin in leaves reached a very significant difference between clones,and the content of chlorogenic acid in leaves reached a significant difference between clones.The coefficient of variation of chlorogenic acid content and rutin content in leaves was more than 15% in the two experimental sites.The rutin content in leaves was significantly different between clones and sites.5 clones with high content of medicinal ingredients were selected according to the total value of standard values of chlorogenic acid content,rutin content in the leaves of Yangling experimental site and Lueyang experimental site,which were more than 2 times of the average value of the control group.