Study On Site Quality Evaluation And Selection Of Superior Pedigree Of Litsea Cubeba

Litsea cubeba is an important oil tree species with the combination of medicinal value and spice value in China.This study in hangzhou,zhejiang province,hubei jingshan taizi mountains field and experimental forest of new sand island mountain pale child family,and three jiangnan hilly terrain of fujian clearing forest area of mountain regions of plantation as the research object,based on the 69 sample area,through investigation,site factor,growth traits and economic traits determination and collection of data,using principal component analysis?PCA?,the quantification theory I model,analysis of covariance,the mountain in the studied area meets the plantation site classification and site quality evaluation,and on the basis of the application of comprehensive index method to select mountain pale child good pedigree,basically have the following results:?1?By investigating the growth and economic characteristics of litsea cubeba,the relationship between site factor and the height of L.cubeba tree was analyzed by principal component analysis and quantitative theory I,and the production potential of L.cubeba was evaluated.The results showed that the complex correlation coefficient of quantitative fitting between slope,landform,soil thickness,soil texture and slope direction of the five leading factors and the height of the cubeba tree was 0.47,reaching the extremely significant level.Using the combination of slope,landform and soil thickness,the site types can be divided into 14.According to the quality evaluation analysis of each site type,the results show that the evaluation of the hilly area is excellent,and the slope is higher.Under the site type of medium thick soil layer,the evaluation results were also good.In the study sample,71.4%of the site quality of litsea cubeba forest land was evaluated as good or excellent,while only 28.6%of the site quality was evaluated as medium,with no difference score,indicating that the study area was suitable for the growth of litsea cubeba.?2?The correlation between the height of cubeba tree and the physical and chemical properties of soil.Through the correlation analysis of soil physical and chemical properties,there was a significant positive correlation between soil organic matter and total nitrogen content,were negatively correlated with the correlation coefficients of total potassium,total phosphorus,available phosphorus,available potassium and p H,and had no significant effect,indicating that the contents of soil organic matter and total nitrogen had a direct relationship with the growth of cubeba officinalis l.To mountain pale subtree?y?As the dependent variable,high organic matter?x₁?,total nitrogen?x₂?,total phosphorus?x₃?,total potassium?x₄?,effective phosphorus?x₅?,available potassium?x₆?as the independent variables,Through stepwise regression equation analysis,the regression equation between tree height and nutrients was obtained,and the equation was as follows:y=1.634+1.004x₂-0.034x₄.Through analysis of the correlation properties between tree height and total nitrogen and total potassium,it was shown that tree height and total nitrogen presented extremely significant positive correlation,with the correlation coefficient of 0.174.Tree height was positively correlated with total potassium without significant influence,with a correlation coefficient of 0.058.According to the regression equation of soil physical and chemical properties,the height of L.cubeba can be evaluated,and the total nitrogen and potassium of soil can also be judged.?3?Excellent family selection.Through correlation data analysis,the content of essential oil of L.cubeba fruit was negatively correlated with annual rainfall?-0.34?,significantly positive correlation with annual average sunshine?0.44?;The content of citral in L.cubeba was negatively correlated with the average annual rainfall.Pale child at the same time,according to the mountain,essence oil yield rate and the content of citral composite 33genealogy of volunteers is good choice,15.2%of the overall performance is good,and show that 33.3%of the family can choose good as mountain pale child cross breeding parent family good primary groups,good family of selected f3,f27,f8,f29,f4,and family f27 significantly higher than that of f3,f29,f4.