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为研究粗皮桉重要性状的随世代推进时的遗传规律,为高世代育种提供理论依据,本研究对粗皮桉含244个家系的第一世代、含83个家系的第二世代种源/家系测定林的3年的生长性状、抗风数据进行了较系统的遗传分析和比较.研究发现:生长性状在第一世代的种源间差异极显著(P＜0.01),而在第二个世代的种源间差异常不显著(p＜0.05),在两个世代的家系间差异均显著;第一世代的不抗风种源的抗风能力在第二世代得到显著提高.第一世代生长性状的变异系数小于第二个世代、种源和家系水的稳定性高于第二世代.两个世代的主要生长性状、抗风指数的遗传力处于中等水平(0.10～0.36),第一代的遗传力高于第二世代、抗风指数的遗传力大于生长性状,树高遗传力在第二世代大幅度下降;生长性状与抗风指数间呈强度的负遗传相关.这个结果说明,经两个世代改良后,粗皮桉的生长和抗风能力仍有较大的遗传增益,但随着世代推进其改良重点应放在家系、个体水平;群体水平的速生性和抗风能力的同步改良困难,应采取其他改良对策.“,”In this research genetic analysis was conducted on 2 consecutive E.pellita generations progeny test trial for 3-yr traits that each contained 244 families and 83 families respectively,which provided a theoretical support for high generation breeding practices and investigating the between generation genetic characteristics of Eucalyptus pellita.The results shown:the between provenance differences of growth traits and typhoon resistance index (TRI) were changed fiom very significant (p ＜0.01) to insignificant (p ＞0.05) of the 1 st generation and the 2nd generation.Between family (within provenance) differences were all significant in the 2 generations.The typhoon resistance of low TRI provenances in 1st generation were significantly improved in 2nd generation.The provenance and family level coefficients of variation (CV) of growth traits in 2nd generation were higher than those in the 1st generation.There were significant difference on provenance and family level stability for growth trait in the 1st generation,but not in the 2nd generation.The heritability of growth traits and TRI were mostly on intermediate level in both generation (0.10～0.36).Heritabilities in 1st generation were higher than in 2nd genaration,Heritabilityof TRI were higher than those of growth traits.Heritability of tree height in 2nd generation were sharply droped from 1st generation.The genetic correlations between TRI and growth traits were highly negative in both generations.These results indicated it can still potentially achieve high genetic gain for the E.pellita even after 2 generations improvement.The improvement should focuse on family and individual level in the following generation rather than provenance level.It was hard to improve growth and typhoon resistance simultaneously in population level,other countermeasures were needed to achieve that.