杉木木材材性的遗传和变异研究——Ⅱ.杉木种子园自由授粉子代间木材密度的遗传变异和性状之间的相关性

<正>研究表明:(1)从28个杉木自由授粉家系来看,家系间和家系内在木材密度上都存在着很大的变异性;(2)木材密度的家系和单株遗传力分别为0.50和0.29,表明该性状受到中等强度的遗传效应所控制;(3)木材密度与材积生长之间存在着微弱的负向相关性,说明选择出幼龄材密度高、生长又快的优良品系是可行的;(4)木材的主要力学指标(顺纹抗压强度等)与木材密度之间存在着紧密的线性相关性。最后,对杉木育种中材性改良的若干基本问题,进行了讨论。

INHERITANCE AND VARIATION OF THE WOOD PROPERTIES OF CHINESE FIR II.THE GENETIC VARIATION AMONG OPEN-POLLINATED PROGENIES PRODUCED FROM A SEED ORCHARD OF CHINESE FIR AND THE CORRELATIONS BETWEEN SEVERAL TRAITS

This paper reports the results on 38 12-year-old open-pollinated progenies produced fiom a seed orchard of Chinese fir. The major conclusions are presented as follows: (1) Significant differences among and within 38 open-pollinated families are found for wood specific gravity (SG). This implies that there arc abundant variation sources for selection. (2) Heritability values for SG by progeny analysis arc 0.29 (on an individual basis) and 0,50 (on family mean basis) while from offspring-parent analysis 0.33+G.16 Therefore, it appears that there is a medium degree of genetic control for SG. (3) The weak correlations between SG and volume, for both phenotypic (-0.24) and genetic (-0.199), indicate that it is feasible to develop strains of Chines fir that have high specific gravity and also grow rapidly when they arc young. (4) There are significant correlations between several major mechanical properties (such as modulus of elasticity in static bending (MOE), modulus of rupture (MOR), maximum crushing strength in compressive parallel to grain (MCS), impact bending strength (IBS)) andSG, with correlation coefficients from 0.73 to 0.92. This implies that the selection for juvenile wood of above average SG and mechanical properties can be improved in some degree. Finally, several fundamental problems in wood property improvement of Chinese fir are discussed.