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1.
毛乌素沙地柠条群体分子生态学 初步研究:RAPD证据   总被引:46,自引:12,他引:34  
毛乌素沙地柠条群体是一个杂种带。为了进一步阐明分子变异和基因流与生境或生态过渡带的联系,应用RAPD标记开展了柠条群体的分子生态学研究。根据RAPD数据利用Shannon信息指数估计了6个柠条群体的遗传多样性,发现大部分的分子变异存在于柠条群体之内(82.4%),只有少部分的分子变异存在于群体之间(17.6%)。又利用Nei指数统计了RAPD数据,也证实了大部分的遗传变异存在于群体之内。柠条锦鸡儿群体与中间锦鸡儿群体的遗传分化系数和遗传距离都很小。以上结果都肯定了柠条群体间和种间的基因流动。无论是从多态位点比率还是群体的遗传多样性来看,硬梁和硬梁覆沙群体是最小的,滩地覆沙群体则具有较高的水平。某些RAPD扩增片段的频率在柠条群体间有规律的变化也许具有着特殊的生态学意义,更可能是中性突变的随机固定。根据以上研究可以得出下列结论:①通过比较Shannon指数和Nei指数的统计结果,可以认为,对于异交植物来讲,Shannon指数在统计RAPD数据方面有用。②毛乌素沙地柠条群体之间存在着强大的基因流,物种的杂交性与生态过渡性一致  相似文献   

2.
RAPD标记构建水稻分子连锁图   总被引:50,自引:0,他引:50  
利用随机扩增多态性DNA(RAPD),在一个水稻(Oryza sativa L.)的双单倍体(DH)群体中发展分子标记,仅用52 个RAPD标记建成了一个水稻RAPD分子连锁图。该图覆盖基因组的总长度为898.4 cM (centim organ),标记间的平均间距为17.3 cM,它能与用同一群体构成的RFLP图谱互相补充  相似文献   

3.
巴马小型猪群体遗传结构的随机扩增多态DNA分析   总被引:6,自引:4,他引:2  
目的分析巴马小型猪的群体遗传结构。方法应用经过筛选的 31条引物对巴马小型猪个体基因组DNA进行RAPD扩增,利用从internet网上下载的软件RAPD istance Package ver-sion1.04软件对实验结果进行分析,计算不同个体间的相似系数。结果经RAPD反应,共扩增出275条带,其中多态性带85条,多态性带频率在0~66.7%之间,平均为27.7%。不同个体猪拥有的RAPD条带具有差异,但拥有相同条带个体猪比率较高。该群体猪的相似系数(F)为0.928(0.78~0.97),平均等位基因频率(q)为0.732,最低平均杂合率(H)为0.286。结论巴马小型猪个体具有较好的遗传一致性和遗传稳定性。  相似文献   

4.
中国特有种四合木种群遗传多样性的RAPD   总被引:4,自引:0,他引:4  
张颖娟  杨持 《生态学报》2002,22(11):1917-1922
采用随机扩增多态性DNA(RAPD)技术检测了西鄂尔多斯高原特有种四合木种群5个斑块的遗传多样性。22个扩增引物产生ll6条带,Shannon信息指数和Nei指数对RAPD数据的分析表明:四合木种群存在较高的遗传多样氓,其中千里山斑块的遗传多样性和多态位点比例较高,石嘴山斑块的最低。遗传多样性的86.5%存在于斑块内,斑块间的遗传变异为13.5%。遗传距离与地理距离无直接相关关系。这些结果说明,遗传多样性反映了四合木种群基因组DNA存在较高的变异性;同时各斑块间存在一定的基因流,四合木各斑块可看成是处于同一种群的半隔离状态(meta—种群),对四合木应注意保护遗传多样性丰富的meta—种群。  相似文献   

5.
鹅膏菌属真菌RAPD分析及亲缘关系的研究   总被引:14,自引:0,他引:14  
本文对采自湖南莽山的26种鹅膏菌属(Amanita)真菌进行了随机扩增多态性DNA(RAPD)分析,40个随机引物中筛选出扩增效果较好的6个引物,每个引物能产生1~10条DNA条带,获得的RAPD谱带清晰并呈现多态性OPG15、OPH04两个引物扩增的RAPD谱带能将26种鹅膏菌完全区分开来,通过6个引物的RAPD分析获得的平均相似性系数表明种与种之间的相关系数在20-60%之间,平均链锁聚类分析  相似文献   

6.
对畲族血浆组特异性成分(Gc)、红细胞磷酸葡萄糖变位酶1(PGM1)、酸性磷酸酶(AcP1)、6-磷酸葡萄糖酸脱氢酶(6-PGD)、腺苷脱氨酶(ADA)、腺苷酸激酶(AK1)的遗传多态性进行了研究。Gc与PGM1是用薄层聚丙烯酰胺凝胶等电聚焦分析的,AcP1、6-PGD、ADA及AK1是用淀粉凝胶电泳分析的。各基因座的基因频率分别为Gc*1F0.4722、Gc*1S0.2421、Gc*20.2738;PGM1*1A0.5357、PGM1*1B0.1627、PGM1*2A0.1587、PGM1*2B0.1429;AcP*1A0.1825、AcP1*B0.8175;6-PGD*A0.9683、6-PGD*B0.0278;ADA*10.9881、ADA*20.0119;AK1*11.0000。畲族Gc、PGM1、AcP1、6-PGD和ADA基因为多态,而AK1基因为单态。发现1例带有6-PGD*R和3例带有Gc*1A2变异等位基因的个体,其中Gc*1A2基因频率为0.0119,达到多态水平。  相似文献   

7.
以来自哈尔滨传染性法氏囊病病毒(IBDV) 强毒株(Harbin 毒株,H) 的基因组RNA为模板,用反转录聚合酶链反应(RT- PCR) 的方法得到了其A 节段的全长cDNA 片段,分5'端(1 659bp) 和3'端(1 444bp) 上下两段分别克隆到pGEMB○R - T 载体上,测定了其核苷酸顺序,在长为3 101 bp 中含有两个阅读框ORFA1 和ORFA2 ,分别编码1 012 个氨基酸的前体蛋白(VP2 - 4 -3) 和145 个氨基酸的VP5,ORFA1 和ORFA2 有部分的重叠。将核苷酸序列及推测出的氨基酸序列与已报道的IBDV 血清Ⅰ型和Ⅱ型毒株的相应序列进行了比较,结果表明:H 毒株与其它血清Ⅰ型毒株之间,在核苷酸水平上存在25bp - 267bp 的差异;在氨基酸水平上存在17 ~40 个氨基酸的差异。在VP2 - 4 - 3 内比较显示,H 毒株与P2 、Cu- 1 之间氨基酸的差异最小为1 .7% ,H 毒株与UK661 之间氨基酸的差异最大为3 .9 % 。变异主要发生在VP2 的可变区(206 - 350 位氨基酸) ,在H 毒株所特有的12 个氨基酸当中,该区就占5 个,代表1 .76 % 的变异。VP4、VP3 和VP5区各有  相似文献   

8.
中国棉花枯萎菌生理小种的RAPD分析   总被引:9,自引:0,他引:9  
冯洁  孙文姬 《菌物系统》2000,19(1):45-50
利用随机扩增多态性DNA(RAPD)分子标记方法对我国棉花枯萎菌3个生理小种(3、7、8号)进行遗传多样性分析,以筛选出的10个随机引物对采自我国11个省(自治区)的26个代表菌株及国外3个不同生理小种对照菌株进行RAPD-PCR扩增,共产生了140个RAPD分子标记,其中87.8%具有多态性。通过聚类分析确定了供试小种间的亲缘关系,并寻找到了我国3、7、8号小种的特异条带,为确立我国棉花枯萎菌生  相似文献   

9.
P物质对GABAA和GABAB受体介导的DRG神经元膜反应的调制作用   总被引:10,自引:2,他引:8  
关兵才  李之望 《生理学报》1994,46(5):441-450
实验在幼年大鼠DRG标本上进行。应用细胞内记录观察了SP对GABA反应的调制作用。结果证明:(1)单独滴加SP(5×10(-6)-4×10(-5)mol/L)或浴槽灌流SP(10(-6)-5×10(-6)mol/L)不引起膜电位的改变或仅有轻微的去极化,但却能使GABA引起的去极化反应减小50.8±20.2%(±SD)(20/30);(2)单独滴加SP可使多数受检细胞APD50延长28.7±9.1%(±SD)(10/18);(3)在预加SP后,能使baclofen所引起的APD50缩短效应(20.6±2.9%,±SD)完全消除(4/12)或翻转成APD(50)延长19.3±8.9%(±SD)(8/12);(4)预加GABAB受体激动剂baclofen(10(-4)-10(-3)mol/L)30—90s后明显地抑制muscimol(10-4-10-3mol/L)引起的去极化反应,其抑制效应达54.4±18.8%(±SD)(17/20)。由于DRG神经元的胞体通常可用来作为研究初级传入终末的模型,因而本文实验结果提示:介导伤害性刺激信息的P物质在背角的释放,可能作用于初级传入终末,从而产生对抗GABA介导的突触  相似文献   

10.
螅状独缩虫(Cachesium polypinum)遗传多样性的RAPD分析   总被引:5,自引:0,他引:5  
用随机扩增多态DNA(RAPD)技术对武汉的汉口(CP-1)、汉阳(CP-2)和武昌(CP-3)三个地区缘毛类的螅状独缩虫(Cachesium polypinum)进行了遗传多样性分析。结果表明:这种动物存在广泛的变异,三个地域群体之间的遗传相似度为0.6522-0.7385(平均值为0.6921),各群体之间遗传相似度大小依次为:CP-2-CP-3〉CP-1-CP-2〉CP-1-CP-3。本文对  相似文献   

11.
Randomly amplified polymorphic DNA (RAPD) analysis was used to investigate the genetic variation among populations, between populations, and within populations, relationships between genetic distance and geographic distance, and the molecular variation and population size. The effects of geographic and genetic distances, as well as of genetic differentiation and population size, on genetic variations of Leymus chinensis (Trin.) Tzvel. are discussed. The present study showed that there was significant RAPD variation between the Baicheng region population and the Daqing region population, with a molecular variance of 6.35% (P < 0.04), and for differentiation among area populations of the Daqing region, with a molecular variance of 8.78% (P < 0.002). A 21.06% RAPD variation among all 16 populations among two regions was found (P < 0.001), as well as 72.59% variation within populations (P < 0.001). Molecular variation within populations was significantly different among 16 populations.  相似文献   

12.
Randomly amplified polymorphic DNA (RAPD) analysis was used to investigate the genetic variation among populations, between populations, and within populations, relationships between genetic distance and geographic distance, and the molecular variation and population size. The effects of geographic and genetic distances, as well as of genetic differentiation and population size, on genetic variations of Leymus chinensis (Trin.) Tzvel. are discussed. The present study showed that there was significant RAPD variation between the Baicheng region population and the Daqing region population, with a molecular variance of 6.35% (P 〈 0.04), and for differentiation among area populations of the Daqing region, with a molecular variance of 8.78% (P 〈 0.002). A 21.06% RAPD variation among all 16 populations among two regions was found (P 〈 0.001), as well as 72.59% variation within populations (P 〈 0.001). Molecular variation within populations was significantly different among 16 populations.  相似文献   

13.
不同尺度下野大豆种群的遗传分化   总被引:30,自引:4,他引:26  
为了阐明不同尺度范围内野大豆种群的遗传分化情况,应用随机扩增多态性DNA(RAPD)方法,分别对我国5个纬度8个不同地点的野大豆(Glycine soja)种群及浙江金华地区5个野大豆种群,进行了分子生态学研究。根据RAPD数据计算相似系数及遗传距离并进行聚类分析,发现无论是不同纬度野大豆种群还是金华地区野大豆小种群均存在较高的遗传变异,且不同纬度野大豆种群间的遗传变异与地理纬度有一定正相关。在对金华地区野大豆种群遗传多样怀的研究,利用Shannon指数估算了5个野大豆种群的遗传多样性,发现大部分的遗传变异存在于野大豆种群间(78.5%),只有少部分的遗传变异存在于种群内。本就此探讨了不同尺度下野大豆种群的遗传多样性与环境因子的关系,并对其成因及维持机制进行了讨论。  相似文献   

14.
Guo H Y  Gao Y B  Ma C C  Ren A Z  Wu J B  Wang Y H 《农业工程》2008,28(8):3729-3736
C. microphylla, C. davazamcii and C. korshinskii exhibit a geographical replacement series from east to west on the Inner Mongolia Plateau. Currently, there is still a debate about the taxonomic and genetic relationship among these 3 species. We studied the genetic diversity and genetic relationship among these 3 species by analyzing DNA samples of individual plants from within 10 populations with random amplified polymorphic DNA (RAPD) markers. We identified 678 RAPD loci in total, of which all were polymorphic (PPB = 100%). There were 41 unique loci (6.05%). In general, a trend presented that the genetic diversity of these species decreased from east to west. Further, the genetic diversity was significantly negatively correlated with the local annual mean temperature. Analysis of molecular variation (AMOVA) showed that the genetic variation among these 3 species was only 6.08% of the total genetic variation. Between the species, the genetic variation was insignificant (P = 0.9961). The proportion of genetic variation among populations within each species was 11.90% (P < 0.001) of the total genetic variation, and the total genetic variation mainly existed within the populations (82.02%). Estimated with Shannon's index, genetic differentiation within the populations (Hpop/Hsp) was 0.8013, the coefficient of gene differentiation (Gst) was 0.1603, and the gene flow index (Nm) was 2.6192. This, thus, indicates that there is relatively high gene flow among these populations, and that these 3 species are crossbreeding. The genetic diversity level and the population distribution pattern showed geographic continuity to some extent.  相似文献   

15.
采用RAPD技术对10个具较大地理跨度的小叶锦鸡儿、中间锦鸡儿和柠条锦鸡儿种群的遗传多样性和遗传关系进行了研究.共检测到678个位点,多态条带比率(PPB)为100%;特有位点41个,占6.05%.总体上3种锦鸡儿的遗传多样性表现出自东向西递减的趋势,分析表明其与生长地点年均气温呈显著负相关.AMOVA表明:3种锦鸡儿种间变异只占总体变异的6.08%,且显著性检验表明这种变异不显著;种内种群间的变异占总变异的11.90%;总变异的主要部分来自种群内部(82.02%). 3种锦鸡儿各种群总体分析结果表明:种群内变异比率Hpop/Hsp为0.8013,基因分化系数Gst为0.1603,种群每代迁移数Nm为2.6192,显示种群间存在一定强度的基因流,3种锦鸡儿间表现为异交性.3种锦鸡儿多样性高低及种群聚类分布格局都表现出一定的地理连续性.  相似文献   

16.
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  相似文献   

17.
大别山山核桃天然群体遗传结构的初步分析   总被引:1,自引:0,他引:1  
利用RAPD分子标记技术检测了大别山山核桃3个天然居群的遗传多样性和遗传结构。20条10 bp随机引物共检测到238个扩增位点,其中多态性位点162个,多态位点百分率(PPB)为68.1%。居群水平Shannon’s多态性信息指数(I)介于0.2651~0.2801之间;居群水平Ne i’s基因多样性指数(H)介于0.1789~0.1890之间。遗传变异计算显示大别山山核桃居群间基因分化系数(Gst)为0.4063,分子方差分析(AMOVA)表明居群间基因分化水平为0.4177,居群间基因流(Nm)为0.7306,说明大别山山核桃大部分变异存在于居群内,居群间基因交流相对较少。这一结果符合大别山山核桃风媒、异交的繁育系统特点,但其居群间基因分化程度明显高于异交植物的平均水平(Gst=0.1930)。地理隔离、居群内近交及居群间基因流受阻可能是形成目前大别山山核桃天然群体遗传结构的主要因素。  相似文献   

18.
梭梭(Haloxylon ammodendron(CA Mey.)Bunge)是一种沙漠旱生优势树种,具有重要的生态和经济价值,然而,我们对梭梭种群的遗传多样性和遗传结构所知甚少.本文采用RAPD和ISSR标记对来自古尔班通古特沙漠东南缘的4个天然梭梭种群的遗传多样性和遗传结构进行了检测.5个RAPD引物和8个ISSR引物分别扩增出61和195条带,多态性位点比率分别为83.6%和89.7%,Shannon信息指数分别为0.333和0.367,RAPD和ISSR分析均表明梭梭种群的遗传多样性水平较高.利用分子方差分析(AMOVA)研究梭梭种群的遗传结构,结果表明,大部分遗传变异存在于种群内,通过RAPD分析发现138.2%的遗传变异发生在种群内;通过ISSR分析发现89.4%的遗传变异发生在种群内;而种群间的遗传分化很小.通过RAPD标记没有检测到种群间的遗传分化,ISSR分析表明10.6%的遗传变异发生在种群内.我们推测梭梭种群较高的遗传多样性水平可能源于对异质、高胁迫环境的长期适应,但还需要进一步的研究加以证实.种群间遗传分异低的主要原因是种群间存在强大的基因流.  相似文献   

19.
Gunderina LI  Salina EA 《Genetika》2003,39(8):1059-1065
Intra- and interspecific variation and divergence of multilocus markers for genomic DNA of the sibling species from the thimmi group, Chironomus riparius and C. piger, were studied by PCR with arbitrary primers (RAPD). A high level of RAPD polymorphism was determined in both laboratory and natural populations of these species. The genetic distances were estimated between the C. riparius populations and between the sibling species C. riparius and C. piger. The genetic distance between C. riparius and C. piger was 4 to 5 times higher than that between the C. riparius populations. A comparison of the variation and divergence for the RAPD markers with those for other genomic markers--enzyme-coding genes and chromosomes (linked gene groups)--showed that different components of the genome differed in their contribution to the genome divergence.  相似文献   

20.
Swertia przewalskii Pissjauk. (Gentianaceae) is a critically endangered and endemic plant of the Qinghai-Tibet Plateau in China. RAPD and ISSR analyses were carried out on a total of 63 individuals to assess the extent of genetic variation in the remaining three populations. Percentage of polymorphic bands was 94% (156 bands) for RAPD and 96% (222 bands) for ISSR. A pairwise distance measure calculated from the RAPD and ISSR data was used as input for analysis of molecular variance (AMOVA). AMOVA indicated that a high proportion of the total genetic variation (52% for RAPD and 56% for ISSR) was found among populations; pairwise Φ ST comparisons showed that the three populations examined were significantly different (p < 0.001). Significant genetic differentiation was found based on different measures (AMOVA and Hickory θB) in S. przewalskii (0.52 on RAPD and 0.56 on ISSR; 0.46 on RAPD and 0.45 on ISSR). The differentiation of the populations corresponded to low average gene flow (0.28 based on RAPD and 0.31 based on ISSR), whereas genetic distance-based clustering and coalescent-based assignment analyses revealed significant genetic isolation among populations. Our results indicate that genetic diversity is independent of population size. We conclude that although sexual reproduction and gene flow between populations of S. przewalskii are very limited, they have preserved high levels of genetic diversity. The main factors responsible for the high level of difference among populations are the isolation and recent fragmentation under human disturbance.  相似文献   

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