杉木无性系木材干缩性与吸水性的变异

以102个17年生杉木无性系为试材,对木材的干缩性与吸水性进行测定分析发现,木材干缩性、吸水性在杉木无性系间差异极显著;干缩性变异幅度为3.1%～20.0%,表型变异系数达59.8%;吸水性变异幅度在214.5%～338.1%间,表型变异系数为13.2%。木材干缩性与吸水性均具有明显的无性系方差分量,表明杉木木材干缩性与吸水性受遗传控制。进一步研究显示,杉木无性系木材干缩性遗传变异系数为38.6%,重复力为0.390,均属中低水平;吸水性遗传变异系数值虽较低,但重复力相对较高(0.664),属中上水平;在不同入选率(10%、20%、30%)下,木材干缩性与吸水性随入选率的降低其遗传增益值(绝对值)不断提高。研究还发现,杉木木材干缩性与木材基本密度、心材比间为极显著遗传负相关,与木材吸水性间则表现为极显著遗传正相关;木材吸水性在遗传水平上与胸径、材积、心材比间呈极显著正相关,而与木材基本密度间为极显著负相关。

Variation analysis on the wood shrinkage and hygroscopicity in Cunninghamia lanceolata clones

The shrinkage and hygroscopicity of the wood were analyzed on 102 clones(17-year-old) of Cunninghamia lanceolata.Variance analysis indicated that both the shrinkage and hygroscopicity traits of the wood varied significantly among clones.The shrinkage ranged from 3.1% to 20.0% with 59.8% phenotypic variation coefficient,while the hygroscopicity spanned from 214.5% to 338.1% with the phenotypic variation coefficient of 13.2%.The presence of the variance component in clones suggested a genetic control of wood shrinkage and hygroscopicity in Cunninghamia lanceolata.Furthermore,medium low genetic variation coefficient(38.6%) and repeatability(0.390) for shrinkage trait was identified,and it was found that the hygroscopicity trait presented a relative high repeatability value(0.664) albeit a relatively low variation coefficient in genetics.The absolute genetic gain for shrinkage and hygroscopicity traits increased when the selection ratio was constricted from 30% to 20%,and to 10%.By evaluating the genetic correlation coefficient,it was concluded that the shrinkage trait negatively correlated to DEN(wood basic density) and HR(heartwood ratio) but positively correlated to hygroscopicity(significance <0.01).Positive genetic correlations were found for hygroscopicity with diameter,volume and HR,while the adverse correlation for hygroscopicity with DEN was also observed(significance <0.01).