Variation of seed characters in Korean pine (Pinus koraiensis ) multi-clonal populations

In this study we measured the variations of seed characters and analyzed the correlations among 60 clones of Pinus koraiensis from 4 seed orchards in order to reveal the characteristics and patterns of variations among populations and clones. The results showed that there were rich variations among the seed characters with high level of genetic diversity; the average phenotype differentiation coefficient among population was 29.82% which was less than that within the population (70.18%), indicating that the variation within population was main source for P. koraiensis seed characters. The rest of seed characters except seed length, seed width and the ratio of length to width differed significantly among the populations (P0.05), moreover the P. koraiensis seed characters among clones in one seed orchard also differed extremely significantly (P0.01). Broad heritability ranged from 61.54% to 94.81%, and it was mostly affected by the genetic control. We could get high genetic gain (4.70%-74.52%) by selecting superior clones. The analysis showed that, under the different site conditions, the correlation was very stable between the followings: TKW and kernel mass as well seed coat mass; kernel rate and kernel mass/seed coat mass, crude fiber as well as carbohydrate; kernel mass and seed length, seed width as well as seed coat mass; carbohydrate and the contents of crude fat, protein and polysaccharide; fat content and kernel rate, kernel mass/seed coat mass, protein, as well as polysaccharide; ratio of length to width and the contents of crude fat, protein as well as polysaccharide. The results from pathway analysis and multiple stepwise regression analysis showed that ratio of length to width and carbohydrate content were main factors affecting the fat content in all 4 seed orchards, and the effect of ratio of length to width was greatest. Therefore, this study can offer the practical application values such as re-selecting better clones in seed orchards based on the P. koraiensis seed characters, increasing the values of nutritional contents and improving the quality of the germplasm resources