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分别以位于澳大利亚新南威尔士州北部沿海地区Urunga、Coffs Harbour、Grafton和Casino的4个斑皮桉无性系试验作为研究对象,测定其林木生长性状和木材材性并进行遗传参数估算。研究表明,林木生长性状和木材材性均受到较高的遗传控制,胸径和树高的广义遗传力（H2）在0.46~0.71之间,Pilodyn值的广义遗传力在0.52~0.77之间,FAKOPP值的广义遗传力在0.64~0.85之间;Pilodyn值与FAKOPP值呈显著的正相关关系,但二者与胸径均无显著相关性;环境因子对生长性状和木材材性的影响显著;遗传与环境交互作用对木材材性影响不显著,但对生长性状如胸径有一定影响。 相似文献
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刺槐主要性状遗传参数估算①甘雨（河南省林科所）李柏兴（郑州市园林局）吉顺祥赵天顺（孟州市林科所）师平钧（嵩县林业局）树木表现的性状是其基因型和外界环境共同作用的结果。树木性状遗传参数估算是林木育种的基础，它直接影响着树木育种策略的制定，并对育种效果的... 相似文献
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蓝桉、直干桉重要材性性状的遗传参数和预期增益 总被引：1，自引：1，他引：1
在种子园育种区4个区组内,从蓝按和直干按中各抽30个家系对它们的纤维长度、木材密度的遗传力、遗传相关和遗传增益作了估算.蓝按纤维长度和木材密度的单株遗传力分别为,0.6745±0.0746和0.3546±0.1010;直干按两性状的遗传力分别为0.3416±0.1011和0.0670±0.0850.两树种的纤维长度与木材密度、树高和胸径的遗传相关系数均为正值,而木材密度与树高和胸径的遗传相关系数都是负数.为这两树种提出了选择的主要性状、选择方法和标准,还为高世代育种应注意的事项作了建议. 相似文献
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全基因组选择（GS）是利用覆盖全基因组的高密度遗传标记对复杂数量性状进行预测的育种方法。在林木种苗阶段根据基因组估计育种值（GEBV）可以利用GS进行个体选择,相比常规育种能增强遗传增益、加快选育进程。该方法无需定位与性状相关的数量性状位点（QTL）,相比分子标记辅助育种能极大地提高对微效位点的捕获功效,是具有巨大潜力的林木育种策略。文中系统介绍了GS的概念和优势,及其在林木中的研究现状和应用。我国林木GS研究处于初期阶段,可优先在常规育种较成熟的树种中开展研究,建立林木GS程序为其他树种提供范式。该综述有助于系统了解全基因组选择育种策略和研究进展,并为全基因组选择在林木育种中的应用提供理论和技术信息。 相似文献
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欧洲赤松是美国北部一个重要的观赏树种。有些林木育种计划,已着手改良这个品种的观尝质量,包括:簇叶颜色,茎干端直,生长率和分枝习性等等。为了制定正确的育种计划和预知遗传进展情况,林木育种学家必须了解遗传原因和环境力量形成的表型变量所占的比例,并经常强调用适当的环境因子的空间和时间抽样,从遗传变量中分离出基因型×环境 相似文献
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徐刚标 《中南林业科技大学学报(自然科学版)》1997,(2)
在前人研究的基础上，应用遗传理论，对树木遗传改良过程中常用公式估算的遗传增益与实际获得增益产生偏差的原因，进行了全面系统的分析．确认产生这种偏差的主要原因有遗传力估算的可靠性、个体繁殖系数和群体有效含量大小，以及基因型×环境交互作用等因素．并对在树木育种实践中提高遗传增益预估可靠性、缩小其与实际增益的误差、增强遗传改良效果的方法进行了探讨． 相似文献
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由云南省澄江县14年生桉树实生种子园保留的育种群体4个区组内，从蓝桉和直干桉中各抽30个家系对它们的纤维长度、木材密度、树高和胸径4个性状的遗传力、遗传相关和遗传增益作了估算。蓝桉纤维长度和木材密度的单株遗传力分别为0.6745±0.0746和0.3546±0.1010；直干桉两性状的遗传力分别为0.3416±0.1011和0.0670±0.0850。两树种的纤维长度与其余3性状的遗传相关系数均为正值，而木材密度与树高和胸径的遗传相关系数均是负数。提出以纤维长度和树高作为蓝桉、直干桉的主要选择性状，并提出了选择方法和标准。蓝桉的选择指数方程为I1=Fr+9.9146H；直干桉的为I2=Fr+0.9809H。为下一步高世代育种应注意的事项作了建议。 相似文献
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[目的]在保证遗传力估算精确度较高的前提下,探讨对已有湿地松测定群体遗传力评估最经济有效的调查取样数量(样本量),为遗传选择提供最佳的遗传参数和选择策略。[方法]以61个湿地松22年生半同胞家系的胸径、树高等生长性状和木材基本密度、弹性模量等材性性状测定值为试验数据,利用ASReml-R软件混合线性模型的限制性极大似然估计法(REML)估算各性状在不同参试样本量下的遗传力及其标准误。通过比较分析在不同样本量下各性状遗传力及其标准误估算值的收敛性,讨论样本量对性状遗传力估算的影响,进而确定各性状遗传力评估所需的最少样本量。[结果]对于61个湿地松自由授粉家系测定林,当测定的家系数少于39个或者随机测量的单株数小于600株时,估算的遗传力极不稳定,标准误偏大,随着样本容量或家系容量的增加其精度与准确性逐渐增加;遗传力较低的性状其遗传力估计所需样本量普遍大于遗传力较高的性状。[结论]对本研究的测定群体而言,要获得精确度较高的遗传力估算值,所需测定的湿地松家系数应该大于39个或者随机测量的单株数大于600株;由于材性性状遗传力相对较高,其需要测定的样本量可相对少一些。本文为大型用材树种遗传力估算提供了一个具有参考价值的实例研究,结果及相应的研究方法对于类似遗传测定群体遗传参数估算具有参考意义。 相似文献
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关于发展人工林与建立人工林业问题探讨 总被引：13，自引：1，他引：12
全世界森林面积为 34 5 4× 1 0 8hm2 ,其中 3%是人工林。人工林是重要的森林生态系统 ,在木材生产、环境保护和景观建设中具有重要功能和作用。人工林在生产功能方面的补偿作用 ,使天然林可以更好地发挥生态环境价值、森林娱乐和生物多样性保护功能。人工林可持续经营的前提是遗传材料的正确选择与营林实践艺术的结合以及保证这种结合的林业政策。愈来愈多地使用外来树种营建人工林是全球趋势。人工林对于环境和生物多样性的影响 ,可以通过合理的规划和经营措施得到解决。林木育种与遗传改良和经营制度的技术创新是不断提高人工林生态系统生产力的动力。人工林的可持续经营是一个十分复杂的问题 ,中国人工林实现可持续经营面临技术和体制两方面的挑战 ,但是 ,根本出路在于林业经济体制的改革 ,象农业那样 ,在市场经济环境中实行人工林产业化经营 ,建立人工林业 (Forestplantationindustry)。 相似文献
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《Scandinavian Journal of Forest Research》2012,27(7):681-691
Abstract Genetic selection in forest tree breeding requires multiple traits to be considered simultaneously. Based on an economic breeding objective, traits are weighted according to their economic importance to create an index used for selection. Economic breeding objectives have mainly been developed in animal breeding and have only recently been applied to forest tree breeding. A review of the general methodology highlights the decisions associated with developing economic breeding objectives and their effects. Furthermore, studies concerning economic forest tree breeding objectives provide a bulk of knowledge and practical experience for fast growing, short rotation species. We have identified and discussed challenges when applying this methodology in Swedish tree breeding. Major challenges are: (1) managing the uncertainty of future industrial uses of wood and industrial processing, originating from long rotations; (2) various issues associated with having a production system describing an entire nation; (3) the size and effects of the discount rate; (4) developing models capable of representing genetic changes in the complex and dynamic system of growing and harvesting trees. We believe that these challenges must be tackled by a joint multi-disciplinary effort, involving stakeholders and researchers in several areas (e.g. forest genetics, economics, wood engineering), to make significant progress. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(4):290-291
Abstract In 2001 large areas of Pinus sylvestris L. stands in Sweden were attacked by Gremmeniella abietina (Lagerb.) Morelet. The resultant damage was assessed in five genetic field trials and one clonal seed orchard, with the aims of quantifying the genetic variation in tree responses to G. abietina, studying the genetic relationship between G. abietina susceptibility and growth traits, and examining the implications of the results for P. sylvestris breeding. A comparison of G. abietina damage between plus-tree progenies and seed stand check-lots in each of four tree classes (dominant, co-dominant, subordinated and suppressed) found no significant differences except in the suppressed tree class, where plus-tree progenies were damaged less severely than trees from the seed stands. Narrow- and broad-sense heritability for G. abietina damage traits were in the range 0.22–0.42. Genetic correlations between G. abietina damage and growth traits were weak and not significantly different from zero. The results imply that selection for growth capacity in P. sylvestris breeding programmes using plus-tree selection or field progeny tests does not increase susceptibility to G. abietina. In addition, there is scope for selecting genotypes with increased resistance if this is required in the future. 相似文献
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The initial introduction of Pinus elliottii (PEE) to China occurred in the 1930s, and the planting of this conifer species has now attained close to 3 million ha in the subtropical zone of southern China. A large-scale genetic improvement program for PEE was implemented in southern China to produce fast-growing trees with high wood quality to address the severe shortage of timber production over the last two decades. In this paper, selection for stem volume, basic wood density (DEN) and modulus of elasticity (MOE) was based on the Smith–Hazel index, and a total of approximately 2 000 individual trees from 158 PEE open-pollinated families were selected at 22 years of age. The DEN and MOE for each tree were determined by non-destructive evaluation techniques using the Pilodyn and Hitman Director ST300® acoustic velocity device. The heritabilities and genetic and phenotypic correlations for the traits that were measured were estimated using the residual maximum likelihood approach in the flexible mixed modelling program ASReml-R. The results showed that the heritability estimates for the wood properties were between 0.292 and 0.309, and the heritabilities of the growth traits ranged from 0.129 to 0.216. The genetic correlation between the DENP and acoustic velocity (V?) with MOEP was 0.45 and 0.95, respectively. An indirect selection based on V was observed to be highly effective for determination of MOE. It indicated that V can be integrated into tree improvement programs as a useful index of MOE by ranking candidate families or individuals within the selection population. The genetic correlations between the growth traits and wood properties were not significant. By contrast, the phenotypic correlations between them were significantly positive, but the correlation coefficients were very low. The appropriate selection index (I4), which placed 10 times as much weight on DEN and MOE as the equal emphsis method, was determined as the appropriate selection index. 相似文献
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云南松种质资源与遗传多样性研究进展 总被引：2，自引：0，他引：2
云南松是分布于我国西南地区的重要造林树种,约占云南省森林分布面积的70%,是云南省重要的经济及用材树种.掌握云南松种质资源保存与利用现状,弄清种源间遗传多样性及遗传变异规律,是完善林木资源、开展林木良种选育的重要基础.因此,对我国近年来学者在云南松种质资源收集、保存及遗传多样性方面进行的研究工作进行了整理、分析.结果表明,对云南松的形态、生理、生态、遗传与种质资源保存等方面的研究已取得许多新的成果,揭示了云南松丰富的遗传资源及多样的地理种源. 相似文献
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