德昌杉无性系种子园生长性状异速生长关系初步研究

本文以德昌杉无性系种子园为研究材料,对38年生30个无性系870个分株的胸径、树高和冠幅进行生长量统计分析,以及从异速生长指数上分析不同无性系间生长量上的差异。30个无性系的胸径、树高和冠幅的均值分别为28.24 cm、19.18 m和5.18 m,其变异系数的均值分别为0.29、0.19和0.24;胸径-树高、胸径-冠幅异速生长关系分析显示德昌杉的在胸径生长量上分配的速率明显高于树高和冠幅,表明无性系间胸径、树高和冠幅的异速生长轨迹发生了显著变化;胸径-冠幅和胸径-树高之间的SMA斜率在不同无性系间,无相同的SMA斜率,除16和28号无性系的胸径-树高外,差异均显著(P<0.05),30个无性系间没有一致的生长量分配速率。无性系间异速生长关系的差异导致不同的生长量分配模式进一步体现了环境对各构件生长的生态可塑性和无性系间生长性状存在着丰富的遗传变异,为德昌杉优良无性系的早期选择提供了可能性。

Preliminary Study on Allometric Growth Relations of Growth Traits in Clonal Seed Orchard of Cunninghamia unicanaliculata

In this paper,the Cunninghamia unicanaliculata clones in China were used as research material.The DBH,tree height and crown width of 87038-year-old clones from 30 clones were statistically analyzed,and the growth difference between different clones was analyzed from the allometric growth index.The mean values of DBH,tree height,and crown width of the 30 clones were 28.24 cm,19.18 m,and 5.18 m,respectively,and the mean coefficient of variation was 0.29,0.19,and 0.24,respectively.The analysis of the relationship between DBH-tree height and DBHcrown width allometric growth showed that the growth rate of DBH was significantly higher than that of tree height and crown width,indicating that the allometric growth trajectories of the DBH,tree height and crown width among the clones have changed significantly.The SMA slope between DBH-crown width and DBH-tree height was not the same among different clones,except DBH-tree height of clones 16 and 28,the differences was significant(P<0.05),and there was no consistent growth distribution rate among 30 clones.The difference in allometric growth relationships among clones lead to different growth distribution patterns,which further reflected the ecological plasticity of environment to the growth of various components and the existence of rich genetic variations in clone growth traits,threrfore providing the possibility for the early selection of superior clones of Cunninghamia unicanaliculata.