指数选择在林木遗传育种中的应用

本文对Smith—Hazel指数的结构、计算方法及其在林木育种中的具体应用作了详细的阐述。理论和实际研究结果表明:用可靠的遗传参数估计值构成的Smith—Hazel指数,始终比简单指数或其它选择方法更为有效,由于它运用了家系信息,限制了性状间不利相关的影响,引入了林木早～晚期相关关系,故具有重要的使用价值。同时,指数结构中对重要的且具较高遗传力的经济性状人为地给予较高的b值,使选择效率更高,选择方法更趋合理。     

标记辅助选择(MAS)与林木遗传育种

介绍了标记辅助选择的研究现状、研究内容、标记辅助选择效率。阐述了林木特性对标记辅助选择的影响,标记辅助选择对林木育种的作用及2个研究实例。     

如何管理林木长期育种项目中的遗传多样性

讨论了长期林木育种项目中遗传多样性的重要性和必要性，影响其变化的主要因素以及对其实行有效管理的途径。认为，通过不同的育种措施，可以实现遗传增益和多样性之间适当的协调以及多样性的合理使用。     

浅谈林木育种的作用及发展策略

本文根据辽宁省林木衣种研究和良种生产的状况,阐述林木育种在林业建设中的作用及存在的问题,并提出今后发展策略或措施。     

分子标记辅助选择在林木育种中的应用

历史上,数量遗传学被认为是指导林木育种的唯一有效工具,这有两个方面的原因：第一,在林木上具有重要经济价值的性状,如树干材积生长、木材纤维长度及适应性等,均是以数量方式遗传的性状,并且控制这些性状的每一个过程是假设受微效多基因所控制的;第二,林木具有很长的世代间隔,很高的遗传杂合性和很高的遗传负荷,这些特性限制了一些经典的遗传材料,如近交系,突变体及特异类型的产生。然而,传统的数量遗传学方法用于指导林木育种的实践并不是完美无缺的。林木个体高大,占地面积大,且大多栽植在非农用耕地上,这样的环境异质性在很大程度上影响性状遗传力的提高,有些林木树种人工杂交比较困难,很难获得足够大的家系,从而产生不平衡的交配设计。Ｎａｍｋｏｏｎｇ 和Ｒｏｂｅｒｄｓ（１９７６） 认为,不平衡的交配设计很难获得准确的遗传参数估计。到目前为止,大多数成功的林木育种方案往往都是基于对表型的简单选择。这种表型选择不能利用林木固有的非加性效应,以及对异质环境的反应潜能,因而育种效果是极为有限的。分子标记技术为现代数量遗传学的发展提供了新的方向。通过利用中性标记与影响数量性状的位点（ＱＴＬ） 之间的连锁关系,人们已经提出了一套统计方法用来鉴定重要的Ｑ     

国际林木抗病育种的基本经验

文章概述了近４０年来国际林木抗病育种研究的经验。突出地介绍了作为抗病性育种主体的寄主和病原菌两个对立系的遗传和变异。认为从现有林分中选择高抗性个体是当前行之有效的抗病育种途径，而制定快速、有效和大批量人工接种鉴定入选个体抗性的方法又是抗病育种的中心。建议强化我国林木抗病育种的研究，以为发展集约人工林服务。     

日本的林木育种事业

日本的林木育种事业开始于1957年,在过去的40多年里,日本的林木育种取得了很大的成果。介绍了日本的林木育种简要历程、林木育种机构、林木育种事业的三大内容（新品种培育、森林遗传资源保存和海外技术合作）、育种成果及对未来育种的期待。     

林木分子标记辅助选择育种

生物外部形态的多样性来源于内部基因的多态性理论的发展，使遗传分子标记在林木选择育种中显示了巨大的潜力。该文通过简述RFLP、RAPD、AFLP、STS和SNP等几种常用分子标记的特点，概述了其在林木育种研究中针对QTL进行标记辅助选择育种的应用情况，并描绘了其广阔的应用前景。     

林木常规育种与生物技术的应用

林木育种的根本任务是选育和繁育林木优良繁殖材料,是实用性很强的学科。该文简要介绍了林木育种的发展历程,选育良种的主要途径及国内外取得的主要成就及对生产的贡献,并评价了我国与林业发达国家当前的发展水平。生物技术的兴起是客观的需要,也是科学技术发展的结果,概括了林木遗传标记和基因工程取得的主要进展,并论述了生物技术在林木中应用的特点和展望。笔者认为,正确处理常规育种技术与生物技术的关系,是持续、健康、高效发展我国林木育种,发展林业生产的基础,新技术与常规育种是相互依存、相互促进的两个方面,但当前应实施以常规育种为主的育种策略。     

Increased forest production through forest tree breeding

Forest tree breeding started in the middle of the twentieth century and since then the use of improved forest regeneration material has become an essential part of forestry in many countries. This review describes methods and achievements of tree breeding programmes, which aim at increasing the quantities and improving qualities of wood-based raw materials through selection, field testing and controlled crossings. Most improved materials currently deployed are seed crops from first-generation phenotypic or tested seed orchards, which offer 10–25% gains in yield depending on the selection intensity of parent trees. Methods of vegetative propagation are developed intensively so that it could be applied to a larger range of species, because it offers high genetic gain and uniformity of the material. Genomic tools are also developed to enhance the efficacy of selection. Applications of genetic engineering are currently limited to research purposes. Forest tree breeding will be an integral part of bioeconomy in securing the production of good quality raw materials in large quantities and will have a significant economic impact on the profitability of forestry in the long term.     

Economic weight of tree survival relative to volume production in tree breeding: A case study with Pinus sylvestris in northern Sweden

Abstract

The primary aim of the study was to estimate economic weights of survival relative to volume production per unit area, and to analyse the observable impact of changing survival, for five different breeding populations of Scots pine in northern Sweden. The economic weights were calculated from the model previously presented by the authors. Data from genetic field trials associated with the breeding populations were used both to estimate economic weights and to analyse the validity of the model. The breeding populations used were chosen to encompass a range of climatic conditions. The effects on the estimates of economic weights of increasing harshness (expressed as decreasing temperature sum), actual levels of both survival and patchiness of survival, and different initial stand densities were also analysed. The results showed that an appropriately parameterized model can be used to estimate economic weights for Scots pine in northern Sweden. Both the economic weight of survival and the observable impact of changing survival varied markedly between the studied breeding populations. Decreasing temperature sum had no trend with increasing economic weight of survival whereas decreasing survival and increasing patchiness of survival increased the estimated economic weight of survival more than three-fold.     

The genetic and economic gains from forest tree breeding programmes in Scandinavia and Finland

Plantations of genetically improved forest trees are critical for economic sustainability in forestry. This review summarizes gains in objective traits and the resulting economic impact of tree breeding programmes in Scandinavia and Finland. Genetic improvement of forest trees in these countries began in the late 1940s, when the first phenotypically superior plus-trees were selected from natural environments. The main findings from this review are that (i) tree breeding can increase volume growth in the range 10–25%, and (ii) the bare land value associated with genetically improved trees gives a better return on investment and a shorter rotation period compared to the unimproved forests. As some Nordic countries are quite dependent on the forest industry, breeding programmes that have resulted in economic gains have been beneficial for society. Growth and wood quality traits are often adversely correlated, and the weighting of traits from an economic perspective could provide an index for determining maximum profit from breeding. Tree breeding faces an array of challenges in the future, such as changes in silviculture, climate, new pests and diseases, and demand for wood-based products.     

红皮云杉良种选育技术研究

对14 a生不同种源家系红皮云杉营建的子代测定林的树高和胸径进行调查,并对其进行方差分析和多重比较,结果表明:不同家系间的树高和胸径生长存在显著差异,树高生长表现最好的家系为M185(361.33 cm),超过群体平均值(290.17 cm)24.52%,超过最差家系M016(239.78 cm)50.69%,超过对照3(298.80 cm)20.93%;胸径生长表现最好的家系为M180(4.12 cm),超过群体平均值(3.23 cm)27.55%,超过最差家系M176(2.34 cm)76.07%,超过对照3(3.41 cm)20.82%。综合树高、胸径2个生长性状,选择M185、M180、N10、M9112、M136、N02为优良家系,其树高和胸径的遗传力分别为0.62和0.63,遗传增益分别为13.36%和19.46%。     

A model to estimate economic weight of tree survival relative to volume production taking patchiness into account

Abstract

Economic weights are needed for genetic selection to weigh different traits in multitrait breeding. The aim of this study was to develop, for commercial forest species, a model for estimating economic weights of survival relative to volume production per unit area. The model takes the patchiness across a stand and the polygenic nature of the factors influencing survival into account and consists of three submodels. The first submodel calculates volume production and a patchiness coefficient, using a production area that is divided into smaller units or production cells. The patchiness coefficient is defined in the model as the variance of survival between the production cells. The second submodel calculates volume production as a function of survival and the patchiness coefficient. The third submodel is a threshold model, which transforms the genetic change in survival from the observable scale to the underlying (liability) scale, thus providing a measure of economic weight. The model behaviour was studied using growth functions for Pinus sylvestris L. in northern Sweden. Both the absolute value of survival and its patchiness coefficient affected the projected production per unit area. When survival was higher than 50%, the relative economic weight of survival increased with decreasing survival and an increasing patchiness coefficient. The relative economic weight of survival was found to be insensitive to changes in site index and harvesting age, but was clearly affected by different initial stand densities.     

沙松选优技术研究

通过分析沙松解析木找出沙松胸径早晚期相关关系，制定沙松优树标准，为建立沙松无性系种子园打好基础。     

杨树杂交育种育子代选择

为选育优良的杨树新品种,以美黑杨、小青杨×箭黑杨、香杨和黑小杨为母本,以小黑杨单倍体()、1344()、黑小杨、合作杨×小山杨、小黑杨为父本进行人工杂交育种。苗期测试结果表明,各杂交组合子代苗高、地径以及抗病性间存在显著差异。通过综合选择,得到7个综合性状表现优异的组合:苗高分别超过对照17%、14%、13%、9%、7%、6%、4%;地径分别超过对照21%、19%、3%、8%、8%、6%、5%。     

杉木优良家系选择的研究

应用杉木382个半同胞家系的子代测定数据,分析主要生长性状的变异原因和规律,估算重要数量性状的遗传参数,探讨抗逆性的表达和遗传差异。 选出可在川南和川东南杉木产区推广的速生型优良家系和川西杉木产区推广的抗逆速生型优良家系共119个,材积的平均增产率约43％、遗传增益约22％。 根据杉木生长性状间的相关,树高年度相关和亲—子树高、胸径、材积的相关研究,讨论了杉木遗传改良中的一些技术问题。     

优良珍稀濒危树种扦插繁育初报

对影响优良珍稀濒危树种扦插成活率的各相关因素进行了研究。结果表明:①不同树种,相同药剂处理,其扦插成活率差异明显;②5种药剂中以“ABT”1号生根粉处理效果最佳;③药剂处理的最适浓度为50~200 mg/kg;④扦插时间以5~7月效果最好;⑤不同类型扦条生根率差异较大。