高等植物细胞质遗传的研究进展

综述了高等植物细胞质遗传主要物质基础质体和线粒体的遗传研究进展。高等植物细胞质遗传表现为多种形式,包括母系遗传、父系遗传和双亲遗传,母系遗传是细胞质遗传的主要特征,但是不能代表细胞质遗传的全部内容;被子植物的质体多数表现为单亲母系遗传,大多裸子植物的质体则为单亲父系遗传;高等植物线粒体有母系、父系和双亲遗传现象的存在;细胞质遗传的本质是细胞器DNA的传递。被子植物花粉发育中雄性生殖细胞中核外DNA的保存或丢失是质体和线粒体遗传的基础。     

林木遗传改良与我国21世纪林业可持续发展

概述了我国林木遗传改良的发展和现状,分析了我国林木遗传中存在的问题,阐述了生物技术（基因工程、细胞工程,分子遗传标记）在林木遗传改良研究中的应用,论述了林木遗传改良在我国林业可持续发展所起的重要作用,最后提出了林木遗传改良进程中生物技术发展的重点领域,包括基因构建、高密度遗传图谱构建和ＱＴＬ定位、材性分子遗传改良和抗逆、抗病虫基因工程育种。     

基因组学发展对传统林木遗传改良的影响

通过对传统林木遗传改良的成就进行概述,分析了基因组研究的发展对传统林木遗传育种的影响,基因组时代的林木遗传改良方法。研究结果表明,传统的林木遗传改良在提高林木生长量和抗性等选育方面取得了显著的成果,单一或者几个树种成为一个国家或地区的主要造林树种成为可能;基因组学的发展从基因的水平对认识林木的遗传本质提供了信息,也丰富了传统遗传改良的方法和手段,必将加速林木遗传育种的进程;基因组学只是辅助传统林木遗传育种的工具,不可能替代传统林木遗传改良理论、方法和技术。     

生物的遗传与变异

遗传和变异是生命过程中的一对矛盾,遗传是保守的,而变异才是前进的。没有遗传,不可能保证物质的相对稳定性。没有变异,就不可能产生新的性状,物种的进化和新品种的选育就不可能了。生物的遗传与变异,经过自然选择形成了适合人类需要的各种品种,因此,遗传、变异、选择是生物进化和选育新品种的三个依据,生物的变异,大体上分为遗传的和不遗传的变异。遗传的变异是指变异发生,能够遗传下去,并在后代重复出现,它是由于有机体内遗传基础发生变化所引起的。不遗传的变     

昆虫遗传多样性研究及展望

遗传多样性研究层次主要有细胞、蛋白质和DNA。介绍了遗传多样性的基本含义和现状。从3个层次对昆虫遗传多样性的研究方法和研究内容进行了评述,其中着重讨论遗传多样性的研究进展,并提出了DNA序列变异尺度将成为今后遗传多样性的研究重点。     

森林遗传资源保护现状及技术问题

本文从国际性组织的活动、几个较发达国家和我国3个方面介绍了森林遗传资源保护的现状.叙述了遗传资源保护中的技术问题.我国应加强统筹规划, 研建森林遗传资源管理系统, 编制遗传资源区划图, 开展有利于遗传资源保存的天然林施业.     

榛属植物遗传基础研究进展

本文详细概述了到目前为止榛子遗传多样性、遗传结构、品种鉴定等遗传基础研究进展情况,以期为省内今后榛子基础研究与遗传改良提供借鉴。     

植物线粒体遗传的研究进展

对植物线粒体遗传方式、遗传机理的最新进展进行了综述。被子植物线粒体的遗传方式以单亲母系遗传占绝对的统治地位,在裸子植物中,不同的种差别较大,松科、红豆杉科线粒体多为母系遗传,而南洋杉科、杉科、柏科和三尖杉科的线粒体主要为父系遗传方式。绝大数植物线粒体遗传有其不同于质体遗传的特征,线粒体在雄性生殖细胞中持续存在,甚至参与受精进入合子,但又更多地表现为母系遗传。     

遗传标记技术及其在林木遗传育种中的应用研究

论述了不同遗传标记技术的原理及特点，综述了遗传标记技术在林木遗传育种中的应用研究进展，为林木遗传学和育种学的研究提供参考。     

滇榛(Corylus yunnanensis)SSR引物的筛选

滇榛是我国西南地区的一个重要榛属资源,本文成功筛选到滇榛9个SSR标记,并对滇榛群体遗传多样性与遗传结构进行了初步分析,结果显示滇榛群体具有中等程度的遗传多样性与遗传分化,这为滇榛遗传改良研究奠定了基础,也有助于推动本地区榛属资源的保护与可持续利用。     

A population genetic study in a scattered forest species, wild service tree [Sorbus torminalis (L.) Crantz], using RAPD markers

Wild service tree [Sorbus torminalis (L.) Crantz] is a forest tree widespread in Europe, characterized by a scattered distribution. Its hermaphroditic flowers are pollinated by insects, and outcrossing is the prominent mating system, also due to the presence of gametophytic self-incompatibility. Genetic diversity and differentiation of 22 populations from northwestern Italy were investigated by means of variation scored at 53 polymorphic RAPD (Random Amplified Polymorphic DNA) loci. Populations differed in genetic variation, with Shannon diversity index ranging from 0.166 to 0.469. According to Analysis of Molecular Variance (AMOVA), most of the genetic variation was found within populations (61.78%) with a significant proportion of variance attributable to genetic differences between regions (23.60%) and between populations (14.62%). Evidence for isolation by distance was found in the set of populations sampled. The effect of habitat fragmentation on genetic variation was also evaluated. The efficacy of RAPD markers in analysing genetic variation, and the contribution of the results in terms of the preservation of biodiversity are discussed.     

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     

Tree species-specific effects on soil microbial residues in an upper Michigan old-growth forest system

Microbial contribution to carbon and nitrogen cycling in forestsoils is important, and may depend on tree species. The amountof amino sugars and their ratios can serve as reliable indicatorsfor bacterial and fungal contribution. We compare forest floormicrobial residues (amino sugars) beneath three canopy-treespecies (Sugar Maple (SM), Acer saccharum Marsh; Basswood (BA),Tilia americana L.; Eastern Hemlock, Tsuga canadensis L.) replicatedin five plots in an upper Michigan old-growth forest. We hypothesizedthat because individual tree species develop a unique microbialcommunity over time, they will accumulate microbial residuesto different degrees. In this study at three tree species sites,the absolute amount of fungal residue (glucosamine (GluN)) wasrelatively constant, while absolute quantities of bacterialresidues (galactosamine (GalN) and muramic acid (MurA)) wereleast in the Hemlock site. Amino sugar ratios revealed thatmicrobial residues were compositionally distinct in the threesites. The lower ratios of GluN to GalN and GluN to MurA inBA and SM sites relative to Hemlock site indicate the lowernet accumulations of GalN and MurA in Hemlock site. In termsof microbial contribution to carbon and nitrogen cycle in forestsoils, we suggest that caution may be needed when using aminosugars as a tool, especially for nitrogen pool assessment, asthe amino sugars are diluted by plant-derived litter. This studyprovides information on the microbial residues in undisturbedforest soils which may assist interpretation of data derivedfrom managed or damaged forests in the future.     

分子标记SRAP及其在林木研究中的应用

分子标记SRAP是近年来发展起来的新型分子标记系统, 具有简单、高效、稳定、部分共显性、扩增片段易测序等优点。它可检测基因的可读框(ORFs)区域, 揭示DNA序列的多态性。介绍了SRAP标记的基本原理与流程, 综述了该标记目前在遗传图谱构建、遗传多样性分析、QTL定位、基因组图谱比较、转录图谱绘制、基因克隆等方面的研究进展。尽管SRAP标记在林木研究中的应用刚刚开始, 但已显示出十分广阔的应用前景。     

林木遗传图谱构建和数量性状基因定位

本文简要介绍了９０年代以来利用ＲＦＬＰ和ＲＡＰＤ分子标记的构建林木的遗传连锁图谱，并应用高密度的遣传连锁图谱上的分子标记进行林木重要数量性状的ＱＴＬ作图，进而阐明了控制多基因的数目，确定ＱＴＬ在染色体上的位置，测定单个基因的作用效应，遗传连锁图谱构建和数量性状基因定位预示林木遗传育种研究将产生深刻的变革。     

A Reappraisal of the Importance of Cronartium ribicola on Pinus strobus in Great Britain

Because of the possibility of serious infection by Cronartiumribicola (White pine blister rust), Pinus strobus, the Weymouthpine, is now very rarely planted in British forests. An assessment,in 1962, in a number of experimental forest plots of P. strobusestablished in 1953 and 1954 showed that initial infection ofthe trees while growing in the nursery may be an important factorin causing later damage and losses in the forest. The resultsalso indicated that the risk of infection in plantation cropsas a result of spore dispersal from black currants in the localityis much lower than is generally thought. It is suggested thatif P. strobus is raised in nurseries which are relatively isolatedfrom currants and if protective chemical spraying against thedisease in the nursery is carried out, the incidence of infectionin plantations at least half a mile from the nearest currantsis likely to be low. The disease cannot spread within a pinecrop by direct transmission from tree to tree.     

分子标记在林副特产育种上的应用现状和前景

概述了分子标记在林副特产指纹图谱构建、遗传图谱构建、QTLs定位、分子标记辅助选择、遗传多样性分析、杂种鉴定等方面的研究进展,同时提出了分子标记在林木上的发展趋势。     

Spring Frosts Affecting the Establishment of Second Rotation Crops in Thetford Chase

Spring frosts in Thetford Chase cause a major reduction in thegrowth of young Corsican pine and very severe frosts or repeatedfrosting may kill the trees. Records of temperatures taken ona range of sites and in different conditions have shown that(a) spring frosts occur every year at Thetford, but the severefrosts which kill trees outright may only occur once every fewyears, (b) frost damage to plants mainly occurs when the treesare less than 18 in (45 cm) tall, (c) forest clearings largerthan 5 acres (2 ha) do not act as artificial frost hollows,(d) cold air flows down slopes of more than 1° and accumulatesat the bottom, forming a frosty zone. Studies showed that frost damage can be minimized by (a) completecultivation, (b) deep ploughing, (c) underplanting, and (d)strip felling. The benefits of these measures are demonstratedby temperature records and by measurements of tree growth. Methods of reducing frost damage are necessary in areas proneto spring frosts if crops of Corsican pine are to be successfullyestablished at low cost.     

Population genetic diversity and regional differentiation of Chinese forest frogs (Rana chensinensis) in Heilongjiang Province

The Random Amplified Polymorphism DNA (RAPD) markers were used to study the intra-specific diversity and regional differentiation of the Chinese forest frogs (Rana chensinensis), which were sampled from the fields of 8 regions in, Heilongjiang Province. Totally 78 polymorphic DNA loci were amplified by 10 RAPD primers. By genetic distance analysis and phylogenetic tree reconstruction with the Neighbor-Joining (NJ) method the results showed that the populations of Chinese forest frogs distributed in 8 regions existed great differentiation (Average Fst=0.347, SD=0.235) while, there was the paradox between geographic distances and genetic distances. Based on geographic and geological data, a hypothesis was posed that it is very possible that the hilly lands in the downstream of the Songhua River and the Heilong River were the center of the origin of the Chinese forest frogs in Heilongjiang Province. And mainly through the Songhua River system, the Chinese forest frogs dispersed into the Songneng Plain from the Sanjiang Plain whereas the Fangzheng region became a sub-center for the western dispersion. Foundation item: This project is supported by the Natural Science Foundation of Heilongjiang Province (C9726). Biography: XIAO Xiang-hong (1960-), female, professor in College of Wildlife Resources, Northeast Forestry University, Harbin 150040, P.R. China. Responsible editor: Zhu Hong     

林木分子标记研究进展

分子标记技术大大促进了林木有关研究的发展,林木分子标记研究主要包括林木遗传连锁图谱构建,比较基因组研究,数量性状位点定位,标记辅助选择,系统演化及群体遗传变异和多样性等内容。迄今,已有近２０个树种构建了基因组遗传连锁图谱,少数树种还进行了基因研究。