Analysis On The Yield Of Branch And Genetic Relationship Of Scion-seed Trees Of The Liriodendron Chinense X Tulipifera

In this paper, we studied on the growth of branches for cuttings, and the morphologic characteristic of the scion-seed trees of the Liriodendron Chinense x tulipifera which have been selected for the establishment of cutting orchard, and analyzed genetic relationship of the scion-seed trees using SSR markers. This study was to achieve the main purpose of providing the basis for select high-quality scion-seed tree to establishment the Liriodendron Chinense x tulipifera propagation system. The results as follows:1.Through direct measurement of the total length and diameter of branch showed a significant difference, particularly in total length. So the branch length would be as an important standard for selection. The total length of secondary branches was longer than primary branches. The productivity of branches for cuttings should be taken into account.2. Evaluated and selected 18 individuals as superior scion-seed trees, and the scion-seed trees comes from Nanjing Forestry University nursery were the best than the other two provenances.3.The total length of branches for cuttings in the higher position of trunk were more than the lower position of trunk ,the middle position of trunk had yield least. Through the anova analysis, different position trunk had great variation in the length of different branch. The primary branches germinated in the lower position mainly, and the third branches were germinated in the higher position mainly. The better the plant growth before transplant, the higher branches been yielded. The scion-seed tree in different phonological types had great variation in branch yield.4. 28 pairs of primers of SSR showed significant genetic diversity among whole individuals. The mean of observed and expected heterozygosities were 0.6404 and 0.7087.5.In strict parameter setting, paternity analysis found 124 scion-seed trees'parents, the assignment rate was 65%, and there were 26 half-sib families, 21 full-sib families, 9 clones; in relaxed parameter setting, paternity analysis found 25 scion-seed trees'parents, the assignment rate was 13%, and there were only 13 half-sib families, 1 full-sib family. With the software parameters set into strict condition, the results of paternity analysis were more reliability, but some real parents cannot be found.6. Evaluated and selected 9 excellent candidate parents had more offspring, and 7 outstanding combinations of parents. The offspring of Backcross tended to more branch yield.7. Cluster analysis shows that Liriodendron Chinense x tulipifera and Liriodendron tulipifera were closer in genetic relation.8. Through paternity analysis on scion-seed trees, the results showed the genetic relationship among scion-seed trees which contained half-sib families, full-sib families, even clones. There were 9 clones which contained 19 individuals, so corrected the total number of scion-seed trees'genotypes from 190 to 180. The genetic information would be significantly useful for the management of cutting orchard, the afforestation with clones, the selection and utilization of parent with the germplasm resources.