| IVThe masson pine (Pinus Massoniana) was the major material species in our country, and possessed very important position.The genetic analysis on 14 characters of the progeny from 26 cross combination of Pinus massoniana in Wu Yi Forestry Farm in Fujian Province was carried out. The genetic diversity of the 26 offsprings was analyzed by microsatellite (SSR) markers. At the same time, SSR markers linkaged with growth traits were detected.The main results were as follows:1. The combining ability analyse on main characters were compliated:①The SCA of different characteres were different in same combination, and the SCA of the same character was different in the different combination. For example: the variation rang of SCA effects was from -1.0719(A52)to 2.9610(A3)in height; The value of SCA effects was also different for the same combination in different traits, such as combination No.A1, which was 0.5244 in diameter at breast height(DBH), while it was -0.1164 in crown width. Furthermore, proposals were posed on parent-selection of main traits in Pinus massoniana.②The values of SCA effects of different cross combination were very significantly in different traits. and the same combination in different traits were also different. meant that to get the heigh values of SCA effects of all characters from one cross was impossible. By the study of their combining ability, we selected A2, A5 and A1 combinations.2. The results of genetic components and heritabilities of the main characters were as follows.①Additive effects were important for straightness ,diameter of stem where branch-whorl originates, crown width,etc; additive and non-additive effects were equally important for height, DBH, diameter and length of branches, branch numbers, etc; non-additive effects were important for the other characters.②The heritabilities in broad sense of height, stem volume, height DBH ratio, taper, branch numbers, etc, were relatively high(73.54%～97.64%)and those of diameter of stem, internode and clean length, etc, were relative low(30%～41.60%). The heritabilities in broad sense of the other characters were in the middle. The narrow heritabilites of height, staightness, crown width, branch number were higher than 50%.3. The relationship between growth and quality traits in SCA effects were studied. In SCA, there was a closely correlation of growth and quality traits for combination, and a positive significant correlation between height and clean height, DBH and crown width; height showed a positive correlation with crown DBH ratio; None of the quality traits showed correlation with stem volume, exept for height DBH ratio.Using model correlation analysis, the first canonical variances of SCA of quality traits had the better forecasting ability to growth traits except diameter of branches, branch numbers, height DBH ratio and crown DBH ratio, and the first canonical variances of all growth traits had the better forecasting ability to quality traits.4. Genetic correlation and path analysis were studied. The results of correlation among main characters showed that there was a remarkable relation between growth and quality character. Straightness, clean height, internode length were principal traits for height, and their relative importance was straightness > clean height > internode length. Diameter of stem, taper, diameter of branch were principal traits for DBH, and their importance was diameter of stem > taper > diameter of branch; Diameter of stem was principal trait for stem volume.5. Ten polymorphic SSR primers were selected from 169 primers developed in P. taeda, P. radiate, P. sylvestris, P. cembra, et al. The number of alleles per locus varied from 3 to 11, and the total polymorphic alleles in all loci were 63 and 6.3 on average.6. Full-sib families showed a high genetic diversity. The analysis compared between the full-sib families and half-sib families showed that: the mean alleles, the effective number of alleles (Ne), the Shannon's diversity index (I), mean expected heterozygosity (He) and the Nei diversity (Nei) of full-sib families which were 6.3, 2.083, 0.9277, 0.5141 and 0.5123 were all higher than full-sib families'5.6, 2.032, 0.8996, 0.4293 and 0.4239 respectively.The result indicated that the full-sib progenies keeped a higher level of genetic diversity.7. Correlation between seven growth traits (such as height, DBH, et al.) and molecular markers was detected. Of all traits, the markers associated with height were not detected, and three markers of RPTest11, PtTx3013 and PTest4, associated significantly or extremely significantly with other 7 traits were detected. The two markers correlated with ratio of height and DBH simultaneously, and accumulative proportion achieved 33.12%, and proportion of PTest4 was 18.56%. Correlation detection indicated that some QTLs effecting growth traits maybe exist near loci. |
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