高黎贡山自然保护区长蕊木兰遗传多样性的ISSR分析

长蕊木兰是具有重要分类和观赏价值的国家一级保护植物。采用ISSR分子标记技术,对云南省高黎贡山自然保护区长蕊木兰3个居群62株个体的遗传多样性进行了研究。结果表明:15个引物共检测到187个有效位点,其中多样性位点171条,在物种水平上多态位点百分率(PPB)为91.44%,居群水平上整顶(ZD)居群PPB最高(66.30%),大蒿坪(DHP)居群PPB最低(21.93%);居群间的基因分化系数(Gst=0.2294)、Shannon居群分化系数(0.27)和分子遗传变异分析(AMOVA)的变异百分率(居群间的变异百分率为27%,居群内的变异百分率为73%)均表明,长蕊木兰遗传变异主要存在于居群内部;聚类结果显示,最大的一类中涵盖了3个居群的绝大多数个体;Mantel检测遗传距离与地理距离之间不存在明显相关性(r=-0.519,P=0.323)。这些结果表明,长蕊木兰具有较大的遗传多样性,但居群间有较大的遗传分化。文章分析了长蕊木兰的濒危原因并提出保护策略,即通过加强已建自然保护区的管理,实施就地保护是最佳选择。     

新疆阜康荒漠地区叉毛蓬居群的遗传结构和分化

应用RAPD技术,对新疆阜康荒漠地区叉毛蓬进行了居群遗传分析。结果表明：①用14个随机引物对5个叉毛蓬亚居群的98个个体进行了RAPD扩增,共检出3919条扩增片段,多态带3868条,总的多态位点百分率为98．7％;②Shannon多样性指数(HPOP／HSP＝0．6933)和Nei基因多样性指数(HS／HT＝0．6948)显示出大部分的遗传变异存在于叉毛蓬亚居群内,遗传分化系数(GST＝o．3052)表明亚居群问的分子变异占居群总遗传变异的30％以上;②5个叉毛蓬亚居群间的平均遗传距离为0．1817,变异范围从0．1258到0．2445,与同一物种亚种间遗传距离的变幅较一致(0．02—0．20),表明5个亚居群间产生了遗传分化;④叉毛蓬亚居群的基因流Nm＝1．138,低于一般广布种的基因流水平(Nm＝1．881),且远低于毛乌素沙地柠条的基因流(Nm＝5．9529),相对有限的基因流可能在叉毛蓬居群遗传分化的维持中起着作用。以上分析表明,尽管大部分的遗传多样性存在于叉毛蓬亚居群内,但5个亚居群间已有明显遗传分化的趋势。     

云南穗花杉的遗传多样性研究

采用随机扩增多态DNA(RAPD)方法对云南穗花杉(Amentotaxus yunnanensis)4个居群和台湾穗花杉似(Amentotaxus for9rmosana)1个居群共104个个体进行了遗传多样性分析。9个随机引物共扩增出清晰谱带143条。云南穗花杉在物种水平上遗传多样性较高(多态位点百分率P为79．0％,基因多样性指数He为0．2718),但云南穗花杉和台湾穗花杉居群内遗传多样性均较低(P为18．0％、6．9％;He为0．0688、0．0198)。云南穗花杉居群间遗传分化强烈(AMOVA,GST和Shannon多样性指数分别为0．7611,0．7503和0．7526)。据推测,第四纪冰川引起的瓶颈效应,小规模居群引起的遗传漂变及幼苗成活率低等因素都加剧了居群间的遗传分化。建议对所研究的云南穗花杉全部居群予以保护,特别是对云南西畴和贵州兴义市七舍两个具有相对较高遗传多样性的居群应该优先建立就地保护点,以达到最大限度保存云南穗花杉遗传多样性的目的。     

基于ISSR的硬叶兜兰居群遗传多样性研究

利用ISSR标记对7个硬叶兜兰居群160个体扩增,10对引物共扩增出101个条带,其中多态性条带97个,种水平上的多态性条带比率(PPB)达96.02%,香侬指数(I)为0.488 9,Neis基因多样性指数(H)为0.332 4。居群水平的遗传参数,多态性条带比率(PPB)为33.51%,香侬指数(I)为0.194 3,Neis基因多样性指数(H)为0.133 2。总的遗传多样性(H_T)为0.323 9,个体遗传多样性(Hs)达到0.133 2。AMOVA结果揭示居群间遗传分化大,居群间基因流N_m为0.349 2。居群间的Neis遗传距离0.148 1~0.4385。基于UPGMA聚类,在遗传距离为0.327时,7个居群聚为两支,第一支由古林箐和马固、田坝、夹寒箐和杨柳井居群组成,第二支由斗咀和小坝子居群组成,聚类关系反映居群间遗传分化与地理距离无显著相关性。     

采用RAPD标记探讨瓣蕊唐松草(毛茛科唐松草属)的遗传多样性及其地理分布格局

采用随机扩增多态DNA(RAPD)标记对瓣蕊唐松草(Thalictrum petaloideum L.)(毛莨科)11个居群246个体的遗传多样性及居群遗传结构进行了检测.20个随机引物扩增出125个用于分析的条带.结果表明:瓣蕊唐松草在物种水平上具有极高的遗传多样性,多态条带比率(PPB)为96%,Nei的基因多样度(h)为0.3502,Shannon多样性指数(I)为0.519 9;居群间分化比较明显,基因分化系数(GsT)为0.351 1,分子方差分析(AMOVA)表明居群间遗传变异占总遗传变异的38.88%;根据条带频率与平均分类距离和Nei遗传距离分别进行UPGMA聚类,结果基本一致,并且反映出与该种地理分布有一定相关性;长江流域分布的两个居群表现出较高的相似性,并与北方分布的各居群构成独立的两支,显示出这两个居群的特殊性,从而对该物种独特分布区成因是由于冰退回迁造成的观点提供了一定的支持.     

利用ISSR标记对新疆白梭梭居群的遗传多样性分析

利用ISSR分子标记对新疆白梭梭4个居群,105个个体进行了遗传多样性的比较分析。在供试材料中,11个引物共扩增出171个多态位点,多态位点百分率为84．85％,4个居群的多态位点百分率差异在33．92％．40．35％之间。Shannon多样性指数（I）为0．3518,物种水平的Nei基因多样度（h）为0．3482。遗传变异分析表明,物种水平的居群间遗传分化系数Gst为0．6238,居群间的基因流Nm为0．3016。遗传分析表明吐鲁番居群和甘家湖居群的遗传距离最近。     

青藏高原东部矮生嵩草遗传多样性的RAPD研究

基于随机扩增多态DNA（RAPD）方法分析了青藏高原东部矮生嵩草（Kobresia humilis）8个居群的遗传多样性及分化程度。14条随机引物共扩增出194个位点数,其中多态性片段168个。研究表明,矮生嵩草无论是在物种水平（多态条带比率PPB（％）为86．60％,Nei’s基因多样性（h）为0．2622,Shannon’s信息指数（I）为0．3983）,还是在居群水平（PPB=62．65％,h=0．2126．I=0．3185）,都具有较高的遗传多样性,居群的遗传多样性大小与生境有相关性。而且,用SPSS分析得出,8个居群的遗传多样性大小与海拔没有明显相关性。用AMOVA数据表明矮生嵩草的遗传变异主要分布在居群内（83．04％）,居群间变异较小（16．96％）。遗传分化指数Gst也显示了相似的结果（0．1891）。从矮生嵩草8个居群的遗传距离和聚类分析发现,以及用NTSYS对矮生嵩草8个居群的的遗传距离矩阵与地理距离矩阵间的关系进行Mantel检测,其结果表明各居群间的遗传距离与地理距离之间没有明显相关性（r=0．37779,P=0．9718〉0．05）。     

金花茶遗传多样性的ISSR分析

采用ISSR分子标记对金花茶的4个自然分布居群的126份样品的遗传多样性水平进行了研究。用12条引物,共检测到105个清晰的扩增位点,其中多态性位点79个,多态位点百分率(PPB)为75．24％。采用POPGENE软件进行分析,结果表明：居群总的Nei’s基因多样性指数为0．2302,Shannon信息多态性指数为0．3502,金花茶总的遗传多样性水平较高。但金花茶居群内的遗传多样性相对较低。基因分化系数为0．5752,遗传变异主要存在于居群间。用NTSYS软件对样品进行UPGMA聚类分析,结果4个居群的样品各自聚在一起,而金花茶两间断分布区区内的居群又各自聚在一起。金花茶4个居群间的遗传距离与地理距离呈显著的正相关(r=0．68261,P=1．0000)。     

濒危植物毛瓣金花茶遗传多样性的ISSR分析

采用ISSR分子标记对毛瓣金花茶6个自然居群的遗传多样性进行了分析。利用11个引物对150个个体进行了扩增,共扩增出92条条带,其中多态性条带74条。毛瓣金花茶在物种水平和居群水平都表现出相对较高的遗传多样性,在物种水平上,多态位点百分率(PPB)为80.43%,Nei’s基因多样性指数(h)为0.245 1,Shannon多样性指数(I)为0.377 6;在居群水平上,PPB为58.70%~66.30%,h为0.199 7~0.229 3,I为0.300 9~0.343 8。Nei’s遗传多样性分析和AMOVA分析表明,毛瓣金花茶的遗传变异主要存在于居群内,居群间的遗传分化程度较低(Gst=0.126 6,Φst=11.37%),基因流(Nm)为3.448 0。Mantel检测表明,居群间的遗传距离和地理距离之间存在显著的相关关系(r=0.755 1,P0.05)。研究认为,毛瓣金花茶较高的遗传多样性和较低的遗传分化可能与其异交型繁育系统和鸟类传粉有关。     

南方红豆杉不同居群遗传多样性的RAPD研究

用随机扩增多态性方法对广东、湖南、江西等3省的12个南方红豆杉自然居群进行了基因组DNA多态性分析,从100条引物中共筛选出10个引物,获得RAPD谱带86条,多态性谱带占51％。聚类分析结果表明：南方红豆杉居群间的遗传距离与这些居群的地理分布相关,即相同或相邻产地的居群间的遗传距离较小,不同产地个体间的遗传距离较大。粤北南方红豆杉的9个居群的遗传多样性较低,可能与近年来资源遭到严重破坏,及其生长缓慢、种子萌发率低、成活率不高等原因有关。     

Genetic diversity in North American ginseng (Panax quinquefolius L.) grown in Ontario detected by RAPD analysis

Genetic diversity within North American ginseng (Panax quinquefolius L.) grown in Ontario was investigated at the DNA level using the randomly amplified polymorphic DNA (RAPD) method via the polymerase chain reaction (PCR). A total of 420 random decamers were initially screened against DNA from four ginseng plants and 78.8% of them generated RAPD fragments. Thirty-six of the decamers that generated highly repeatable polymorphic RAPD markers were selected for further RAPD analysis of the ginseng population. With these primers, 352 discernible DNA fragments were produced from DNA of 48 ginseng plants, corresponding to an average of 9.8 fragments per primer, of which over 45% were polymorphic. The similarity coefficients among the DNA of ginseng plants analyzed were low, ranging from 0.149 to 0.605 with a mean of 0.412, indicating that a high degree of genetic diversity exists in the ginseng population. Lower levels of genetic diversity were detected among 3-year-old ginseng plants selected on the basis of greater plant height than among the plants randomly selected from the same subpopulation or over the whole population, suggesting that genetic factors at least partly contribute to morphological variation within the ginseng population and that visual selection can be effective in identifying the genetic differences. The significance of a high degree of genetic variation in the ginseng population on its potential for improvement by breeding is also discussed.     

亚欧美栗疫病菌群体的遗传多样性

从 12 0个随机引物中筛选出条带清晰、主带明显、重复性好的 9个引物 ,对来自不同地域和寄主的 7个群体的 14 2个栗疫病菌菌株进行 RAPD分析。 9个引物共扩增出条带 12 4条 ,其中多态性条带 111条 ,多态性比率为 89.5 2 %。利用 Popgen3.2软件对供试群体进行遗传多样性分析和 UPGMA聚类。结果表明 ,中国地区 4个群体间的遗传相似性较大 ,与美国、意大利和日本群体间的相似性较小 ;美国和意大利群体间的遗传相似性较大 ,且它们与日本群体间的相似性大于与中国群体间的相似性。病原菌群体的遗传变异率为 0 .2 35 1,其中在地区水平上 ,82 .34%由群体内的变异引起 ,17.6 6 %由群体间的差异引起 ,群体间的基因流动值为 2 .3311;而在寄主水平上 ,则 79.4 2 %由群体内的变异引起 ,2 0 .5 8%由群体间的差异引起 ,群体间的基因流动值为 1.92 97     

Genetic diversity among Balkan trout populations based on RAPD analysis

Random amplified polymorphic DNA (RAPD) markers were used to estimate the population structure and phylogenetic relationships among samples of the Salmo trutta complex that inhabit the Balkan Peninsula. Five random oligodecamers were selected to amplify DNA from 140 fish from seven populations. Using these primers, 55 discernible DNA fragments were generated, of which 50 (90.91%) were polymorphic. The statistical results indicated that there was low genetic diversity within populations (with an average percentage of polymorphic bands (P) of 11.69% and a Nei's genetic diversity index (h) of 0.035), but at the same time high genetic differentiation among populations (F(ST) = 0.89). The distribution of genetic diversity among Balkan trout may result from their evolutionary history and reflects genetic drift coupled with bottleneck phenomena. Overall, RAPDs proved valuable tools for quick and reliable stock discrimination and provided information that might be useful regarding conservation and management of trout.     

Genetic variation within and among populations of a wild rice Oryza granulata from China detected by RAPD and ISSR markers

Genetic variation within and between five populations of Oryza granulata from two regions of China was investigated using RAPD (random amplified polymorphic DNA) and ISSR (inter-simple sequence repeat amplification) markers. Twenty RAPD primers used in this study amplified 199 reproducible bands with 61 (30.65%) polymorphic; and 12 ISSR primers amplified 113 bands with 52 (46.02%) polymorphic. Both RAPD and ISSR analyses revealed a low level of genetic diversity in wild populations of O. granulata. Furthermore, analysis of molecular variance (AMOVA) was used to apportion the variation within and between populations both within and between regions. As the RAPD markers revealed, 73.85% of the total genetic diversity resided between the two regions, whereas only 19.45% and 6.70% were present between populations within regions and within a population respectively. Similarly, it was shown by ISSR markers that a great amount of variation (49.26%) occurred between the two regions, with only 38.07% and 12.66% between populations within regions and within a population respectively. Both the results of a UPGMA cluster, based on Jaccard coefficients, and pairwise distance analysis agree with that of the AMOVA partition. This is the first report of the partitioning of genetic variability within and among populations of O. granulata at the DNA level, which is in general agreement with a recent study on the same species in China using allozyme analysis. Our results also indicated that the percentage of polymorphic bands (PPB) detected by ISSR is higher than that detected by RAPD. It seems that ISSR is superior to RAPD in terms of the polymorphism detected and the amplification reproducibility. Received: 29 March 2000 / Accepted: 15 May 2000     

重金属污染下曼陀罗种群分化的RAPD分析

将不同空间地段上获得的同一种质但污染年代各不相同的4个曼陀罗材料种子易地种植在同一模拟重金属污染生境中,对这4个曼陀罗种群进行RAPD分析,结果表明,在105个检测位点中发现有78个位点呈多态性。在这些多态位点中未发现与重金属抗性有关的特异性多态DNA片段。S hannon-Weiner指数计算结果表明,在短期污染时间内曼陀罗种群遗传多样性水平降低。随着污染时间的推移,曼陀罗种群逐渐在污染迹地上稳定下来,曼陀罗种群遗传多样性水平有所回升和提高,4个曼陀罗种群遗传多样性由高到低排列顺序为L＞CK＞M＞S。遗传多样性指数表明曼陀罗种群间变异程度远小于种群内的遗传变异。4个种群两两间遗传距离较小,遗传距离最大的种群为L和S,最小的为L和CK种群。因此,在重金属胁迫环境选择下,曼陀罗种群发生了一定程度的分化与微进化,轻高水平的遗传多样性可能是植物适应重金属污染胁迫环境的基础。     

应用RAPD标记技术对树鼩遗传多样性的分析

目的建立树鼩RAPD（random amplified polymorphic DNA）遗传标记分析方法,了解中缅树鼩种群的遗传多样性。方法采用PCR技术对40条随机引物进行优化,筛选出能有效用于树鼩群体遗传分析的RAPD位点,对48只树鼩个体的基因组DNA进行PCR扩增,并应用Popgene 1.32与RAPDistance Package Version 1.04等软件进行数据处理,分析树鼩的群体遗传特性。结果20个RAPD引物共检测到113个位点,平均每个引物可扩增出5.65个位点,其中多态位点数为69个（占61.1%）。个体间的遗传相似系数平均为0.8307,个体间遗传距离在0.09-0.27之间,平均遗传距离为0.1693。雄性群体的遗传多态度（H0）（0.1864）略高于雌性群体（0.1470）,平均遗传多态度（Hpop）为0.1667;树鼩遗传多态度所占的比例在群体内为48.29%,而雌、雄群体间为51.71%。NJ法进行聚类分析得出T15、T33和T47号树鼩个体聚类成一大类,其余45只树鼩个体聚成另一大类,雌、雄个体呈相互交叉现象。结论实验所筛选的随机引物可有效用于中缅树鼩种群的遗传结构分析。本树鼩群体具有较好的遗传多样性。     

Genetic diversity among chicken breeds estimated through randomly amplified polymorphic DNA.

The randomly amplified polymorphic DNA (RAPD) markers were used to detect polymorphism among five breeds of chicken i.e. White Leghorn and Rhodes Island Red (selected for part period egg production and egg mass respectively), Red Cornish and White Plymouth Rock (selected for early body weights) and Kadaknath (native breed). Twelve of the fifty random primers screened yielded distinct polymorphic RAPD profiles. Of the total 96 fragments amplified, about 25% showed polymorphism. Using the RAPD data matrix, the within population and between population genetic similarity was estimated. The selected improved breeds showed higher within population genetic similarity in comparison to the native breed. The two meat type breeds showed a high level of genetic similarity between themselves. The White Leghorn breed showed a low genetic similarity with other breeds. The native breed showed highest similarity with Rhodes Island Red. The dendogram was constructed to show phylogenetic relationship among these breeds. As expected, the genetic distances were lowest within similar type breeds and were highest between dissimilar type breeds. The results indicated the effectiveness of RAPD in detecting polymorphism between chicken populations and their applicability in population studies and establishing genetic relationships among the chicken populations.     

Genetic diversify among Balkan trout populations based on RAPD analysis

Random amplified polymorphic DNA (RAPD) markers were used to estimate the population structure and phylogenetic relationships among samples of the Salmo trutta complex that inhabit the Balkan Peninsula. Five random oligodecamers were selected to amplify DNA from 140 fish from seven populations. Using these primers, 55 discernible DNA fragments were generated, of which 50 (90.91%) were polymorphic. The statistical results indicated that there was low genetic diversity within populations (with an average percentage of polymorphic bands (P) of 11.69% and a Nei’s genetic diversity index (h) of 0.035), but at the same time high genetic differentiation among populations (F _ST = 0.89). The distribution of genetic diversity among Balkan trout may result from their evolutionary history and reflects genetic drift coupled with bottleneck phenomena. Overall, RAPDs proved valuable tools for quick and reliable stock discrimination and provided information that might be useful regarding conservation and management of trout.     

濒危灌木长叶红砂遗传多样性的RAPD分析

应用RAPD分子标记对濒危灌木长叶红砂(Reaumuria trigyna)种群遗传多样性进行了分析.应用18条随机引物对长叶红砂5个种群的95个个体进行扩增,检测到118个位点,其中多态位点105个.结果表明:长叶红砂种群的多态位点比率(P)为88.98%,显示出长叶红砂种群存在较高的遗传多样性.Shannon多样性指数(0.4966)、Nei基因多样性指数(0.3303)和基因分化系数(Gst=0.1425)的分析结果显示,长叶红砂种群遗传变异大多存在于种群内,种群间的遗传分化占14.25%.聚类分析表明,长叶红砂种群遗传距离与地理距离之间无直接相关关系.遗传多样性水平与物种特性和所处不同群落有关,濒危植物并不一定表现为遗传变异水平的降低.     

羊草种群遗传分化的RAPD分析Ⅱ.RAPD数据的统计分析

对松嫩草原上分布的灰绿型和黄绿型羊草9个种群进行了15个引物的RAPD分析,统计结果表明,两类种群的扩增片段数和多态位点比率明显不同,黄绿型种群低于灰绿型,其值分别＜90与＞100,＜50％与＞70％,比较了7种不同统计方法据RAPD表型或基因型频率估算的种群遗传多样性,几种统计结果都揭示,黄绿型种群低于灰绿型种群,用F1s值矫正种群对Hardy-Weinberg平衡的偏离后,估算等位基因频率,通过Shannon指数和Nei指数估计羊草种群间分化分别为37．6％和35．7％,高于等位酶的分析,讨论比较了等位酶和RAPD分析结果的异同。