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1.
林木分子标记研究及其在育种中的应用   总被引:1,自引:0,他引:1  
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 2 0个树种构建了基因组遗传连锁图谱 ,少数树种进行了目标性状位点定位研究 ,定位了为数不多的与分子标记连锁的数量性状位点。林木分子标记已在育种策略制定、辅助选择育种、基因型鉴别 ,以及目的基因的分离和克隆等分子育种研究中广泛应用。  相似文献   

2.
介绍在松树遗传群体育种中遗传标记的特点,并总结遗传图谱构建、数量性状基因定位和与功能基因组相关的EST序列的研究进展,并对目前分子标数量性状基因定位和基因组在松树育种中应用的局限性、存在问题和未来发展方向进行了讨论.  相似文献   

3.
介绍在松树遗传群体育种中遗传标记的特点,并总结遗传图谱构建、数量性状基因定位和与功能基因组相关的EST序列的研究进展,并对目前分子标数量性状基因定位和基因组在松树育种中应用的局限性、存在问题和未来发展方向进行了讨论。  相似文献   

4.
RAPD技术在林木遗传育种中的应用   总被引:3,自引:0,他引:3  
RAPD是用以检测种一级水平基因多样性的分子遗传标记技术。该文对RAPD标记的基本原理进行了介绍 ,并综述了近年来RAPD分子标记在林木种质资源研究 ,分子遗传图谱的构建 ,数量性状位点定位 ,分子标记辅助育种 ,群体遗传结构及多样性等方面的应用 ,最后指出了存在的问题与展望  相似文献   

5.
遗传图谱是开展数量性状基因定位、标记辅助育种以及基因克隆等研究的基础,在理论和育种实践上都具有重要的意义,本文较为详尽地阐述了林木遗传图谱的构建过程,针对林木的自身特点探讨林木遗传图谱的作图策略,同时指出当前林木遗传图谱构建中存在的问题,并对林木高质量遗传图谱构建提出展望。  相似文献   

6.
林木分子标记研究进展   总被引:19,自引:3,他引:16       下载免费PDF全文
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。  相似文献   

7.
本文简述了世界林木遗传图谱构建研究的现状,重点论述了遗传图谱在数量性状基因位点、分子标记辅助选择、目的基因定位和分离方面的应用情况,并对这一新的研究领域进行了展望。  相似文献   

8.
林木遗传图谱研究的现状与展望   总被引:7,自引:0,他引:7  
本文简述了世界林木遗传图谱构建研究的现状,重点论述了遗传图谱在数量性状基因位点、分子标记辅助选择、目的基因定位和分离方面的应用情况,并对这一新的研究领域进行了展望。  相似文献   

9.
RAPD技术具有快捷,灵敏度高,容易检测等优点,在生命科学各领域获得广泛应用。本文综述了近几年RAPD技术在植物遗传资源研究中的应用,如构建分子遗传图谱、分子标记辅助选择育种、基因定位、遗传指纹作图。  相似文献   

10.
中国杨树分子遗传改良的研究现状   总被引:1,自引:0,他引:1  
杨树是中国广泛栽培的重要造林树种之一 ,我国是世界上杨树资源丰富的国家 .杨树具有速生丰产、实用性强、无性繁殖能力强 ,且基因组较小等特点 ,现已成为研究林木生理和基因工程研究的模式树种 .该文概述了基因工程技术、遗传图谱构建、重要性状基因定位以及分子标记辅助选择育种等方面在中国杨树遗传改良中的应用研究进展 ,并对现代分子生物学技术在林木遗传改良应用中存在的主要问题和应用前景进行了讨论  相似文献   

11.
林木遗传图谱构建和数量性状基因定位   总被引:5,自引:1,他引:5  
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。  相似文献   

12.
林木数量性状位点定位的统计方法   总被引:2,自引:1,他引:1  
本世纪初数量遗传学作为一门独立的学科而产生,以研究实验群体或自然群体的数量性状的遗传变异,它主要研究两个基本问题:(1)总的表型变异中有多少比例属于遗传的影响?(2)有多少遗传因子参与这种遗传变异?如遗传力的概念可以反映遗传因子对表型变异的贡献,它可用亲属间的相关性加以估计.这些参数量已在微生物、动植物中有大量的研究,遗传参数估算对于制定适当的育种计划和理解生物性状的表型进化有重要的作用.  相似文献   

13.
综述了利用分子标记技术构建杨树、松树和桉树等速生树种遗传连锁图的研究进展,并提出了当前林木遗传作图中存在的主要问题。  相似文献   

14.
The R. R. Reynolds Research Natural Area is a 32-ha pine-hardwood forest in southeastern Arkansas, U.S.A., that originated from diameter-limit cutting of the virgin forest before 1915. In 1935, these 32 ha were reserved from timber management. Between 1937 and 1993, eight inventories were taken of all living trees > 9-cm DBH, using 2.5-cm DBH classes within three species groups: Pinus spp., Quercus spp., and other hardwoods. In 1994, all standing dead snags of pines and hardwoods > 9-cm DBH were inventoried by 2.5-cm DBH classes. During 56 years, thc overstory pine-hardwood ratio remained stable in terms of relative basal area, but pine density decreased with a commensurate increase in hardwood density. In 1993, pines represented 63% of basal area but only 23% of stem density. Just before the 1993 inventory, a pine bark-beetle infestation developed on the area, and within one year the pines lost about 2.5 m2/ha in basal area and had 180% more snags than were contributed by hardwoods. The overstory pine component is decreasing in density as a result of natural senescence and the allogenic effects of bark beetles. Hardwood species are expected to eventually dominate the forest because shade-intolerant pine regeneration will not develop to maturity beneath the closed hardwood canopy which can be altered only by catastrophic natural disturbances or anthropogenic intervention.  相似文献   

15.
Quantitative trait locus (QTL) detection was carried out for growth traits in 122 F1 progenies of Pinus elliottiivar. elliottii (PEE) x tR caribaea var. hondurensis (PCH) hybrid. The PCH male parent linkage map contained 108 mark- ers in 16 linkage groups, while the PEE female parent contained 93 markers in 19 linkage groups. Sequence-related amplified polymorphism (SRAP), microsatellite (SSR), expressed sequence tag polymorphism (ESTP) and inter-simple sequence repeat (ISSR) were selected from an existing linkage map. Growth traits investigated were height at age five (HT05) and six years (HT06), diameter at breast height at age five (DBH05) and six years (DBH06) and annual growth from age five to six years of height (AGHT) and diameter at breast height (AGDBH). KruskaI-Wallis and interval mapping approaches were used to estimate levels of significance, the number of QTLs, the percentage of the phenotypic varia- tion explained by each of QTLs and their positions on the genetic linkage maps. Twenty six QTLs with significance levels p 〈 0.05 were detected on the parental maps for the six growth traits, which explained more than 15% of the phenotypic variation, suggesting an existence of major-effect genes. Several QTLs had the pleiotropy controlling more than one sin- gle growth trait. Overall, the proportion of phenotypic variation explained by QTLs ranged from 5.9% to 40.6% for HT05 and HT06, from 6.6% to 42.0% for DBH05 and DBH06 and from 5.8% to 22.3% for AGHT and AGDBH. The results from this study provide a basis for marker-aided selection (MAS) in PEE x PCH hybrids.  相似文献   

16.
Major challenges exist for applied gene conservation of forest genetic resources in native habitats of the Mexican and Central American Pines, Pinus radiata and the Southern US pines. They include population decline and population structure changes, due to forest removal, conversion of forest land to other uses, fires, climate change, diseases and pests. However, tree breeders continue to struggle with methods that would meaningfully integrate tree breeding and conservation populations. In this review, I will start by outlining the importance of gene conservation in tree breeding programs, then highlight some challenges and opportunities for applied gene conservation programs; and lastly, I share results of a large body of applied research and other activities aimed at genetically characterising the base population of P. radiata in Australia and New Zealand, for the purposes of effective ex situ gene conservation. Main threats for species grown in exotic environments also include introduced diseases and pests, and more recently, climate change. Consequently, movement of genetic material is often restricted and genetic resources of pine species are not readily expanded by further importations from overseas. Therefore, conservation of genetic material currently in these countries is likely to be important for the long-term viability of plantation forestry using pine species. In addition to understanding the largely unpredictable or speculative biological and economic worth of rare alleles, the greatest challenge that we have in ex situ gene conservation is to develop practical approaches for infusing genes from base populations of unimproved material into more advanced-generation breeding programs without greatly affecting productivity gains. Other notable challenges include perceived costs and benefits of gene conservation in the face of increasing privatisation of forest estate. While financial resources for domestication of alternative species are declining, a vast number of existing species and provenance/progeny trials of P. radiata, the Mexican and Central American pines and the Southern US pines provide an excellent gene resource for the future.  相似文献   

17.
Acacia hybrids offer a great potential for paper industry in Southeast Asia due to their fast growth and ability to grow on abandoned or marginal lands. Breeding Acacia hybrids with desirable traits can be achieved through marker assisted selection (MAS) breeding. To develop a MAS program requires development of linkage maps and QTL analysis. Two mapping populations were developed through interspecific hybridization for linkage mapping and QTL analysis. All seeds per pod were cultured initially to improve hybrid yield as quality and density of linkage mapping is affected by the size of the mapping population. Progenies from two mapping populations were field planted for phenotypic and genotypic evaluation at three locations in Malaysia, (1) Forest Research Institute Malaysia field station at Segamat, Johor, (2) Borneo Tree Seeds and Seedlings Supplies Sdn, Bhd. (BTS) field trial site at Bintulu, Sarawak, and (3) Asiaprima RCF field trial site at Lancang, Pahang. During field planting, mislabeling was reported at Segamat, Johor, and a similar problem was suspected for Bintulu, Sarawak. Early screening with two isozymes effectively selected hybrid progenies, and these hybrids were subsequently further confirmed by using species-specific SNPs. During field planting, clonal mislabeling was reported and later confirmed by using a small set of STMS markers. A large set of SNPs were also used to screen all ramets in both populations. A total of 65.36% mislabeled ramets were encountered in the wood density population and 60.34% in the fibre length mapping population. No interpopulation pollen contamination was detected because all ramets found their match within the same population in question. However, mislabeling was detected among ramets of the same population. Mislabeled individuals were identified and grouped as they originated from 93 pods for wood density and 53 pods for fibre length mapping populations. On average 2 meiotically unique seeds per pod (179 seeds/93 pods) for wood density and 3 meiotically unique seeds per pod (174 seeds/53 pods) for fibre length mapping population were found. A single step statistical method was used to evaluate the most informative set of SNPs that could subsequently be used for routine checks for mislabeling in multi-location field trials and for labelling superior clones to protect breeder’s rights. A preliminary set of SNPs with a high degree of informativeness was selected for the mislabeling analysis in conjunction with an assignment test. Two subsets were successfully identified, i.e., 51 SNPs for wood density and 64 SNPs for fibre length mapping populations to identify all mislabeled ramets which had been previously identified. Mislabeling seems to be a common problem due to the complexity involved in the production of mapping populations. Therefore, checking for mislabeling is imperative for breeding activities and for analyses such as linkage mapping in which a correlation between genotypic and phenotypic data is determined.  相似文献   

18.
我国南方松树杂交育种研究进展及发展趋势   总被引:10,自引:0,他引:10  
经过近 30年的努力 ,广东、广西松树杂交育种和引种方面取得了较为显著的成果。选育的 PEE× PCC F1具有母本湿地松的树干通直圆满、抗风力强、分枝习性好、耐水渍和父本加勒比松的速生、树皮薄等优点。除适应性广 ,材质好外 ,其遗传增益比亲本增加 30 %以上。本文详细介绍我国南方松树杂交育种研究进展状况 ,阐明了杂交松研究今后的发展趋势  相似文献   

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