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利用ISSR标记对12种五针松亲缘关系的研究 总被引:7,自引:0,他引:7
采用ISSR 标记技术,对12 种五针松的亲缘关系进行分析。利用筛选出的12 个ISSR 引物共检测到117 个位点,多态条带比率(PPB)在9.40%~33.33 %之间,遗传分化最高的是偃松,最低的是柔枝松。12 种五针松的基因多样性(Ht)为26.21%,其中种内基因多样性(Hs)为7.66%,种间基因多样性(Dst)为18.55%,五针松种间变异占总变异的70.78%。遗传距离聚类,将12 种五针松分为2 个类群,第一类群包括乔松、华山松、海南五针松、华南五针松、北美乔松、山白松和云南五针松;第二类群包括美国白皮松、偃松、、柔枝松、西伯利亚红松和红松。图1 表3 参6。 相似文献
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利用ISSR分子标记技术对贵州省马尾松主要分布区天然林群体、贵州省都匀马尾松种子园基因收集区、种子园建园亲本及子代进行了遗传多样性分析,结果表明:贵州省马尾松天然林群体保持较高的遗传多样性;由于种源间基因交流频繁,贵州省马尾松变异主要存在于种源内;都匀马尾松种子园和子代仍然存在较高的遗传多样性水平,人工选育过程中并没有导致遗传范围变窄,种子园还有进一步选择的潜力;种子园收集区遗传多样性较低,需要进一步收集种质资源加以补充。该研究结果可以为贵州省马尾松种质资源的收集与保存、种子园遗传管理以及贵州省马尾松多世代育种策略的制定提供参考依据。 相似文献
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马尾松种质基因资源选择、保存和利用研究 总被引:5,自引:0,他引:5
广西马导松种质资源选择,保存与利用研究项目开展近20年来,通过种源调查与原地保护利用,种源试验与原,异地保存利用,林分试验与原,异地保存利用,以及个体选择与异地保存和改良四个阶段研究,保存种质基因2902年,面积11471.6km2,其中种源215件,林分63件,无性系1806件,家系818件,优良种源增益10%-15%,优良林分增益15-20%,种源,林分供种40.5万kg,造林约69.35万hm2,为区内外提供群体和家系种质1000多份,提供无性系插穗30多万条。 相似文献
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运用随机扩增多态DNA (RAPD)标记对分布于我国4省6病区63份茶藨生柱锈菌寄主红松和华山松进行遗传多样性分析.用6个随机引物对寄主松针进行PCR扩增,共得到138个DNA位点,其中多态位点117个,多态位点比率为84.78%,RAPD的Shannon指数遗传多样性为0.315 5,RAPD的Nei指数基因分化系数为0.525 5.不同来源寄主的遗传多态性规律顺序:辽宁清原红松>云南洱源华山松>山西沁水华山松>云南巧家华山松>四川广元华山松>云南东川华山松.从RAPD聚类分析树状图可以看出,先将63个松针样品分成2个不同的RAPD组群(红松组群和华山松组群),然后又将不同地理来源的华山松组群按地理区域分成5个亚群,同一采集的华山松亚群中又分成感病组和抗病组.研究表明,种间的遗传多样性是由种的遗传属性所决定的,而地理因素只是影响种内遗传多样性的一个因子. 相似文献
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木荷种源遗传多样性和种源区初步划分 总被引:12,自引:0,他引:12
利用RAPD分子标记研究我国高效生物防火和优良用材树种木荷主要分布区15个地理种源的遗传多样性和遗传结构.结果显示,木荷具有丰富的遗传多样性,木荷种内平均基因多样度为0.363 6.研究发现木荷种源Shannon表型多样性与产地纬度呈显著的负相关,南部种源的遗传多样性显著高于北部种源,从而推测25°N左右的自然分布区可能是木荷的分布中心.木荷有27.14%的遗传变异存在于种源间,而72.86%的遗传变异来自于地理种源内.基于分子水平上的种源聚类,可将木荷分布区划分为3个种源区:北缘种源区(安徽南部和浙江北部)、中部种源区(南岭以北、浙江南部以南)和南部种源区(南岭以南),而南部种源区和中部种源区又都可再分为东部和西部2个种源亚区. 相似文献
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白榆优良基因资源的收集保存和利用的研究 总被引:1,自引:0,他引:1
山东省济宁市林业局从1984年在全国完成对白榆种源试验、优树选择和部分省市开展良种选育工作的基础上,进行了白榆优良基因资源收集、保存和利用工作。采用“人工林易地保存”法汇集白榆优良基因资源,并相继开展了无性系测定、子代测定、杂交育种和种子园建设的研究。5年来共汇集榆属树种14个、杂种4个、变种1个,优良种源36个、优良单株61株、优良类型25个。建立基因库8.6公顷,保存基因材料113个。至1990年已生产良种苗18万株,营造试验林和示范林共66.7公顷,已取得了显著的经济和社会效益。 相似文献
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柚木基因资源的特点和我国柚木遗传改良途径 总被引:1,自引:0,他引:1
本文论述世界柚木基因资源的特点及其在我国的发展前途和遗传改良途径。柚木基因资源分成三个互不连续的天然分布区,生态背景十分复杂。种内包括种源间的变异多种多样。印度被视为世界柚木的“多变异中心”而受人重视。我国目前拥有的柚木种源,与辽阔的宜林地很不相称,是发展柚木人工林的障碍之一。世界柚木的基因库,可为我国柚木人工林的发展提供丰富的基因资源。为此柚木遗传改良途径应在地理种源试验或类型划分的基础上,进行混合与单株并行选择,并与无性系育种结合起来。 相似文献
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Washington J. Gapare 《New Forests》2014,45(3):311-331
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
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松树是世界上森林生态系统和人工林的重要树种,松树的遗传改良开展早,进展快,成效大。分子标记技术为缩短育种周期,提高育种效率提供了有力的工具。本文回顾了世界上松树分子标记遗传图谱构建、比较遗传作图、数量性状位点定位和标记辅助选择的研究进展。已经构建遗传连锁图的林木有13个属,近40个树种,其中松树占40%,而大多数松树遗传图谱仍然是不完整的,不能覆盖全基因组;比较遗传作图显示松属树种具有高度的遗传保守性;数量性状位点(QTL)定位表明,大多数性状的遗传基础存在着主效基因,为开展分子标记辅助选择提供了良好的基础。杂种松部分重要性状的遗传控制中存在着树种效应,对标记辅助选择和育种策略的制订具有指导意义。 相似文献
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巨桉遗传改良研究进展 总被引:2,自引:0,他引:2
进行巨桉种源试验和地理变异研究时, 应重视从树种的生物学特性出发, 考虑试材的取样标准、群体的生殖和生态特性, 采用现代生物气候方法综合分析。巨桉有些群体存在着复杂的多型性, 采用复合轮回选择能明显提高自由授粉家系后代的遗传增益, 并提高种子园改良的质量。应用入选家系或个体的无性繁殖材料进行改良, 可获得更大的遗传增益。巨桉遗传改良应把有性和无性两条途径结合起来, 遵循简便、实用和高效的原则;基于这个原则, 本文提出了巨桉目前可能的最佳改良程序。 相似文献
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马尾松材性遗传改良的现状及展望 总被引:6,自引:2,他引:4
概述了马尾松材性遗传改良研究的状况及存在的问题 ,并对未来研究提出展望 :加强杂交育种 ,充分利用现有的遗传测定林 ,探索切实可行的无性繁殖技术和利用林木基因工程技术进行马尾松材性遗传改良 相似文献
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Millettia ferruginea (Hochst.) Baker is a potential agroforestry species endemic to Ethiopia. No documented information exists about genetic variation
in this species, thus baseline information is needed to initiate improvement program. Here, we quantified variations in seed
size, germination and seedling growth at nursery stage based on seeds collected from six sites across the natural range of
distribution of the species in Ethiopia. All seed- and seedling-related traits exhibited highly significant differences among
seed sources (P < 0.01), and the magnitude of genetic variation was substantially higher (77–99%) than the environmental variation. The genetic
advance as percent of the mean was higher for germination capacity (69.4%) and seed weight (31.7%) than for other traits,
suggesting that the population means for these traits may be changed considerably by selecting the superior 5% of the genotypes.
There were strong phenotypic (rp = 0.81) and genotypic (rg = 0.89) correlations between seed width and seed weight, so also between seedling height and root collar diameter (rp = 0.95 and rg = 1.00). In conclusion, the results reveal the existence of substantial genetic variation, which can be utilized to initiate
tree improvement program of the species and for gene conservation in seed banks.
In memory of the late Abraham Loha, who passed away during the writing process. 相似文献
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论中国林木引种驯化策略 总被引:12,自引:1,他引:12
林木引种驯化已经成为现代林业的重要组成部分。从现代林木引种驯化概念出发,对林木引种驯化策略进行了探讨分析,对于中国林业的持续发展,在理论和实践上都是十分必要的。 相似文献
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Dinh-Duy Vu Thi Tuyet-Xuan Bui Minh-Duc Nguyen Syed Noor Muhammad Shah Dinh-Giap Vu Yi Zhang Minh-Tam Nguyen Xiao-Hua Huang 《林业研究》2019,(5):1823-1831
Two threatened dipterocarp species,Dipterocarpus costatus and Dipterocarpus alatus are well-known endangered species in lowland forests of southeastern Vietnam,primarily from habitat loss and over-exploitation of their wood.To develop conservation strategies for these species,we analyzed 242 samples using nine microsatellite markers to determine the genetic variability within and among five populations of D.alatus and three of D.costatus,representing the natural range of dipterocarps in Southeast Vietnam.Results indicated low levels of genetic variability within populations with an average gene diversity of 0.223 for D.alatus and 0.152 for D.costatus.Results of bottleneck tests indicated a reduction in population size of both species(P>0.05).Genetic differentiation among populations was high(FST=0.347 for D.costatus and 0.274 for D.alatus),indicating limited gene flow(Nm=0.662 for D.costatus and 0.47 for D.alatus)and isolated populations related to geographical distances.Analysis of molecular variance showed high genetic variation within populations(72.92%for D.alatus and 60.81%for D.costatus)compared to among populations.Bayesian analysis and UPGMA tree also indicated the two optimal genetic clusters related to geographical distances.These results will provide a platform for the conservation,management and restoration of these species. 相似文献
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锦鸡儿属植物遗传育种研究进展 总被引:1,自引:0,他引:1
通过对锦鸡儿属植物的遗传变异及遗传多样性、基因鉴定与克隆、遗传改良与良种繁育等方面的综述文献研究。结果表明,锦鸡儿属的研究主要为柠条锦鸡儿、小叶锦鸡儿、中间锦鸡儿等少数种;遗传多样性、基因的克隆和功能方面的研究较多,传统育种工作进展缓慢。目前主要依靠种子繁殖,无性繁殖还处于研究阶段;抗性基因结构和功能的研究对培育和筛选高抗逆性锦鸡儿品种具有重要指导意义;油脂相关基因的研究是锦鸡儿属植物生物柴油开发的重要基础工作;良种选育和杂交育种将是以后研究工作的重点。 相似文献