基于马尾松测交系子代的生长、干形和木材密度的配合力分析

利用设置在浙江省淳安县姥山林场的14年生测交系交配设计(测交系未经过一般配合力测定)的遗传测定林,研究马尾松生长、干形和木材基本密度的一般配合力(GCA)和特殊配合力(SCA)及所受的遗传控制。结果表明:马尾松胸径、树高、木材基本密度和干物质积累量皆存在显著的GCA和SCA效应,其全同胞家系遗传力在0.746～0.908间,受较强的遗传控制,其中胸径、木材基本密度和干物质积累量受加性基因效应控制为主、显性基因效应次之,树高受基因的显性效应控制略高于加性效应,而树干通直度完全由加性基因效应影响。统计分析表明,来自中南部的1134、1127和5906测交系其胸径、树高和木材干物质积累量的GCA为正值且较高,而来自北部安徽的3203测交系木材基本密度的GCA最高。在9个待测系中,5476、5158、3205的胸径、树高、木材干物质积累量和树干通直度的GCA均较高,但5476和5158的木材基本密度的GCA则较低,与木材基本密度GCA较高的5910和3205差异显著。马尾松SCA的大小则独立于GCA,因性状和组合而异。依据单株干物质积累量大于总体平均值的20%及树干通直度得分不小于4的选择标准,筛选出7个优良杂交组合,其单株干物质积累量的现实增益和遗传增益分别为22.68%～67.34%和20.25%～60.13%。

Genetic analysis on combining ability of growth, stem form and wood basic density of Pinus massoniana by testcross mating design

The genetic effects of GCA and SCA were estimated for growth,stem form and wood basic density effects for using the 14-year-old full-sib progeny of non-selected Pinus massoniana in a testcross mating design.The results showed that the GCA and SCA effects were significant and full-sib family heritability ranged from 0.746 to 0.908 for DBH,height,wood basic density and dry biomass accumulation which indicated these traits were under strong genetic control.Additive effects played a major role for DBH,volume,stem straightness,wood basic density and dry bimoass.Whereas dominance was next genetic control for these traits.Height appeared to be equally subjected to both dominance effect and additive effect,while stem straightness was complete controlled by additive effect.The statistical analysis showed that GCA of 1134,1127 and 5906 from southeast distribution range of Chinese red pine,were positive and large for DBH,height and wood dry biomass.GCA of 3203,which grew slowly and originated from northern Anhui,was the largest for wood basic density.Among the nine female parents,the GCA of 5476,5158 and 3205 was large for DBH,height,dry biomass and trunk straightness,while the GCA of 5476 and 5158 was lower than 5910 and 3205 which had large GCA for wood basic density.It was not found that GCA of growth and wood basic density was closely related to latitude of habitat.SCA did not show correspondence with GCA,and varied among traits and crosses.Seven crosses were selected according to individual dry biomass exceeding 20 % of the mean and the score of trunk straightness above 4,which could obtain practical genetic gain about 22.68 %—67.34 % and 20.25 %—60.13 % respectively.