| In order to analyze the variation of different Masson pine（Pinus massoniana）families,better carry out the management and utilization of genetic resources in seed orchard,and provide the excellent families for pulp use,genetic variation analysis of growth and wood traits,wood chemical components,radial variation of fiber morphology,phenotypic and genetic correlation among traits were carried out on 58 Masson pine families in Baishan state-owned forest farm,Shanghang County,Fujian Province.The Breggin comprehensive evaluation method and principal component analysis（PCA）were used for selection of Masson pine superior families for pulp use.The main research results were as follows:1)The results of variance analysis and multiple comparison showed that 11 traits,including tree height,diameter at breast height（DBH）,volume,height/DBH ratio,basic density,length of wood fiber,width of wood fiber and length to width ratio of wood fiber were significantly different among Masson pine families（P<0.01）.Cellulose,hemicellulose,lignin,benzene-alcohol extractives content and ash content reached different level among families（P<0.05）.2)In the study of fiber morphology radial variation,it was found that there were two main rules in the fiber length and width of early and late wood.Firstly,from the 1st to the 15th year,the length and width of the early and late wood fiber increase with the growth of ages.Secondly,from the 1st to the 10th year,the wood fibers increased with the growth of the ages,and decreased slightly and then tended to be stable after the 11th year.The regression prediction model of fiber-tree age was established,and it was found that the length and width of morning and evening timber could be predicted from the 3rd year to the 14th year in any year of the 15th year,and the fitting degree was great3)In the correlation analysis between different traits,it was found that there was a significant positive correlation between growth traits,and all the correlation coefficients were above 0.6.In terms of material properties,the length and width of early wood fiber,the length and width of late wood fiber,and the length-to-width ratio of early and late wood were all significant positive correlation.The phenotype and heredity of the length and width of late wood fiber were positively correlated with the width of early wood fiber.The phenotype correlation coefficients were 0.560 and 0.568,respectively,and the genetic correlation coefficients were0.505 and 0.620,respectively.The length of late wood fiber was very significant positive correlated with the width（P<0.01）.The phenotypic correlation coefficient was 0.937,and the genetic correlation coefficient was 0.831.The width of late wood fiber was negatively correlated with the length-to-width ratio of late wood fiber,and the correlation coefficient was-0.328.There was a positive correlation between cellulose and the width of late wood fiber,with a correlation coefficient of 0.414.The tree height,DBH and volume were negatively correlated with the width of late wood fiber,and the correlation coefficients were-0.142,-0.318 and-0.354,respectively.The above results indicated that the correlation between the traits could provide help for directional selection of Masson pine families.4)Through the preliminary evaluation of different traits by Breggin comprehensive evaluation method,it was found that three families including No.2,No.24,No.37 No.19,No.35,No.22,No.54,No.63,and No.62 were superior in growth traits,wood traits and chemical components.After that,the principal component factor analysis method was used to comprehensively evaluate 16 traits,and the comprehensive index equation was obtained as Z=0.17812Z1+0.16266Z2+0.15638Z3+0.11082Z4+0.08522Z5+0.08462Z6.The result of sphericity test was 0.762,and the Z value of the comprehensive index of each family was obtained.At the selected rate of 15%（I=1.755）,9 excellent families were obtained,including family No.24,No.35,No.37,No.22,No.2,No.66,No.19,No.62,and No.38.These families were excellent for pulpuse with great growth traits,wood properties and chemical composition.They could be used as the developed seeds for establishing the stands for pulp use.Through the preliminary evaluation of different traits by Breggin comprehensive evaluation method and the comprehensive index equation,including family No.24,No.35,No.37,No.22,No.2,No.66,No.19,No.62,and No.38.In the same progeny test stand,it is found that there are great differences between the excellent families selected in the young forest period（7-year-old）and that in the middle forest period（15-year-old）.Only No 22 family is the same plus family,which indicates that the selection should be carried out after the trees develop to a certain stage,and the conclusion is more reliable.Through the above analysis,this study provides a basic conclusion for the comprehensive evaluation and selection of Masson pine families for pulp,and also provides a reference for management of the Masson pine seedling seed orchard. |
