亚美马褂木无性系幼林生长性状变异及选择研究

Analysis of Growth Traits Variation and Selection in Young Clones Forest of Liriodendron sino-americanum

为筛选出亚美马褂木优良无性系,并进一步提高杂交育种效率,以30个亚美马褂木半同胞杂交子代优良单株无性系试验林为研究对象,基于造林后连续3年的苗高和地径生长数据,进行方差分析和遗传参数估算,并采用性状表现水平分析法和加权系数法对30个无性系进行综合评价和早期选择。结果表明:造林3 a时亚美马褂木无性系苗高和地径平均值分别为2.27 m和4.49 cm,苗高和地径无性系间差异均达极显著水平(P<0.01);造林3 a时苗高和地径的无性系重复力分别为0.84和0.79,远高于单株重复力;最终定选的4个优良无性系平均苗高和地径分别为3.08 m和5.71 cm,平均遗传增益和现实增益分别达到30.05%、21.38%和35.60%、27.16%。研究显示,亚美马褂木幼林无性系间生长性状变异丰富且受较高的遗传调控,在早期进行优良无性系选择是可行的。

In order to select the superior clones of Liriodendron sino-americanum P.C.Yieh ex Shang et Z.R.Wang, and further improve the efficiency of cross breeding, clonal experimental forest of 30 superior clones from hybrid progenies of half-sib families were studied, based on the growth data of seedling height and ground diameter for 3 consecutive years after afforestation, the analysis of variance and genetic parameter estimation were carried out, then the comprehensive evaluation and early selection were carried out by character expression level analysis and weighted coefficient method.The results showed that the average height and ground diameter of L.sino-americanum clones were 2.27 m and 4.49 cm respectively in 3;year, the difference of height and ground diameter among clones was very significant(P<0.01);In 3;year, the clonal repeatability of height and ground diameter were 0.84 and 0.79 respectively, which was much higher than that of single plant repeatability;The average height and ground diameter of the 4 superior clones were 3.08 m and 5.71 cm respectively, the average of genetic gain and real gain were 30.05%,21.38% and 35.60%,27.16% respectively.The research results indicated that the phenotypic variation was abundant between young forest of L.sino-americanum clones and growth was mainly controlled by heredity that it is feasible to select superior clones in the early stage.