香椿优树半同胞家系苗期生长变异与选择

Growth Variation and Selection of Half-sib Families of Toona sinensis Superior Trees at Seedling Stage

为了从苗期开始研究香椿优树半同胞家系的遗传变异,以来自四川香椿3大主要分布区域的18个香椿优树半同胞家系1年生容器苗为研究对象,进行了苗期生长比较与优良家系选择。结果表明:苗高与产地纬度、年均气温均有显著的正相关性,与海拔呈极显著的负相关性,地径与各环境因子均没有显著的相关性。苗高和地径变幅分别在38.1~101.6 cm之间和4.42~9.14 mm之间,不同家系间均有极显著差异。绝大部分家系苗高和地径的变异系数均小于15%,苗木生长均匀一致。苗高和地径的遗传力分别为0.939和0.762,苗高受到的遗传调控大于地径。以苗高为主进行苗期选择,选择出蓬溪1、5号、合江7号3个优等家系,入选率16.67%,入选家系苗高和地径的遗传增益分别为35.33%和20.19%。入选家系的选择差大,入选率低,遗传增益大,经过造林对比试验后有成为良种的潜力。

In order to study the genetic variation of half-sib families of Toona sinensis from the seedling stage,and 18 one-year container seedlings of Toona sinensis superior half-sib families from three main distribution areas in Sichuan province were taken as the research object,and the seedling growth comparison and superior family selection were carried out.The results showed that the seedling height has a significant positive correlation with latitude and annual average temperature,and an extremely significant negative correlation with altitude,while ground diameter had no significant correlation with various environmental factors.The seedling height and ground diameter varied from 38.1 cm to 101.6 cm and from 4.42 cm to 9.14 mm respectively,with significant differences among different families.The variation coefficients of seedling height and ground diameter of most families were less than 15%,and the growth of seedlings was uniform.The heritability of seedling height and ground diameter were 0.939 and 0.762 respectively,and the genetic regulation of seedling height was greater than that of ground diameter.Three superior families,Pengxi 1,5 and Hejiang 7 were selected,with a selection rate of 16.67%,and the genetic gains of seedling height and ground diameter of the selected families were 35.33%and 20.19%,respectively.The selection deviation of selected families was big,the selection rate was low,and the genetic gain was large.After afforestation comparative test,the selected families had the potential to become good varieties.