Selection Of Hardwood Species And Its Asexual Propagation In Shanxi Province

This research is based on national project (201104012) which was undertaken by Shanxi academy of forestry.This study is aimed to select a number of genes of plus trees and the best asexual reproduction, used appropriate amount of 1 year old branches of plus trees of Ailanthus altissima Swingle, Fraxinus chinensis Roxb, Acer tyuncatum as materials, by means of literature, consultants, field survey in natural distribution area according to the Morphological Quality Index (MQI) of isolated wood and comparative from 3-5 advantages of wood, field trials with "T" shaped budding, chip budding with xylem, scion grafting, cuttings, root breeding. The main results were as follows:Selection of plus trees.58 plus trees of Ailanthus altissima Swingle,50 plus trees of Fraxinus chinensis Roxb and Acer tyuncatum were selected after primaries and repeated election. The height and DBH of selected plus trees were more concentrated,were mainly distributed in the southern region of Shanxi Province as its limiting growth conditions.Best reproduction. The preliminary results was obtained through survey survival rate asexual breeding, grafting is appropriate for asexual breeding of Ailanthus altissima Swingle, "T" shaped budding is appropriate for asexual breeding of Fraxinus chinensis Roxb and Acer tyuncatum. In addition, the strong overwintering branches can significantly improve the survival rate of grafted ash.The optinal clones. Every plus trees which were saved or selected were Continue to multiply in next year.27 plus trees of Ailanthus altissima Swingle were used for scion grafting again, the growth index had significant difference among clones. The second clone of plus trees which had 4 plus trees clone accounting for the total number by 14.8% and get the best evaluation by using of analysis of cluster and evaluation of character. The selection intensity of the optional clones were 1.57. The optinal clones’ heritability of seedling height and ground diameter was 0.61 and 0.54 whose genetic gain was 23.75% and 27.46%, respectively.48 plus trees of Fraxinus chinensis Roxb which were saved in last year were breeded as "T" shaped budding in spring. The fourth clone of plus trees which had 13 plus trees clone accounting for the total number by 8.3% and get the best results of breeding. The selection intensity of the optional clones was 1.84. The optinal clones’heritability of seedling height and ground diameter was 0.90 and 0.87 whose genetic gain was 56.69% and 38.97%, respectively."T" shaped budding was used to sire 46 plus trees of Acer tyuncatum which were selected in last year. The third clone of plus tree which was only one had the best performance. The selection intensity of the optional clones was 1.84. The optinal clones’ heritability of seedling height and ground diameter was 0.72 and 0.49 whose genetic gain was 45.44% and 26.96%, respectively.