厚荚相思半同胞子代生长变异及抗寒性差异的调查分析

Survey and Analysis on Growth Variation and Cold Resistance for Half-Sib Progenies of Acacia crassicarpa

[目的]调查分析厚荚相思半同胞子代生长变异及抗寒性差异。[方法]以1年生38株厚荚相思优树自由授粉家系子代测定幼林为材料,对生长性状的遗传变异状况及经历了2008年初连续低温雨雪冰冻天气过程后植株的耐寒表现进行调查分析,并在生长差异比较基础上初步判定家系优劣,估算遗传参数与遗传增益。[结果]厚荚相思家系间的各生长性状遗传差异均达极显著水平,参试家系间树高、地径和冠幅的遗传变异系数达25.4%～34.5%,这些性状的家系遗传力分别为0.89、0.92和0.92。以树高、地径和冠幅同时大于对照为主要指标进行综合选择,初步选出9个在幼林期表现较为优异的家系,各性状平均遗传增益分别为12.46%、17.95%和17.98%。参试家系中按寒害指数大小排序,抗寒性最强的前10个家系为:35>10>34>26>11>41>17>12>43>1。[结论]抗寒性与生长性状相关分析显示,厚荚相思幼林家系的抗寒水平与主要生长因子间无显著相关性,但树高、地径和冠幅各生长性状间呈现极显著的正相关。

[ Objective ] Growth variation and cold resistance for half-sib progenies of Acacia crassicarpa were studied. [ Method J Based on the investigation of the growth traits and the chilling injury in 1-year-old open-pollinated Acacia crassicarpa progeny test plantation which subjected to a serious cold flow in the early 2008 ,the variation analysis was applied to determine the family quality and to estimate genetic parameters and genetic gains. [ Result I Differences of the growth traits were highly significant among families. The variation coefficients among families of height, ground diameter and crown width reached 25.4% - 34.5% , and the broad sense heritability of these traits were 0.89, 0.92 and 0. 92, respectively. 9 fine families were selected as fast-growing type according to the growth traits of height, ground diameter and crown width with 12.46% , 17.95% and 17.98% of the mean genetic gains, respectively. The order of 10 top strong cold resistance families according to the chilling injury index were： 35 〉 10 〉34 〉26 〉 11 〉41 〉 17 〉 12 〉43 〉 1. [Conclusion]There was extremely significant positive relation- ship between the growth traits, but no significant relationship between cold resistance and main growth factors among families.