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1.
花生根瘤菌群体遗传多样性和系统发育研究   总被引:8,自引:0,他引:8  
杨江科  谢福莉  周俊初 《遗传学报》2002,29(12):1118-1125
利用16S rRNA RFLP,16S rRNA序列分析和16S-23S IGS PCR RFLP技术对43株花生根瘤菌和来自其他种属的15个参比菌株进行了群体遗传多样性和系统分析。16S rRNA PCR RFLP分析结果表明,所有供试花生根瘤菌均属于慢生根瘤菌属,在系统发育上与B.japonicum的亲缘关系最近,具有相同的16S rRNA RFLP基因型,而与B.elkanii相对较远。16S rRNA 序列分析结果表明,供试花生根瘤菌在系统发育上更接近于B.liaoningense,序列间差异小于1%,而B.liaoningense在系统发育上与B.japonicum相距很近,其序列间差异小于1%,16S-23S rRNA IGS RFLP分析结果表明,尽管花生根瘤菌与B.japonicum和B.elkanii的亲缘关系很近,但在71%的相似性水平上供试花生根瘤菌仍各自聚为一群,并可进一步分为A、B、C和D4个亚群,该分群还明显反映了地理因素对群体遗传多样性和系统发育的影响。  相似文献   

2.
Populus simonii Carr. is an important ecological and commercial breeding species in northern China; however, human interference during the last few centuries has led to the reduction and fragmentation of natural populations. To evaluate genetic diversity and differentiation within and among existing populations, we used 20 microsatellite markers to examine the genetic variation and structure of 16 natural populations. Our results indicated that the level of genetic diversity differed among populations, with average number of alleles per locus (AR) and expected heterozygosity (H e) ranging from 3.7 to 6.11 and 0.589 to 0.731, respectively. A marginal population from Qilian in the Qinghai–Tibetan Plateau showed the highest values (AR?=?6.11, H e?=?0.731), and the Zhangjiakou and Yishui populations showed the lowest values (AR?=?4.08, H e?=?0.589 and AR?=?3.7, H e?=?0.604). The inbreeding coefficient (F IS) values for all populations were positive, which indicated an excess of homozygotes. The microsatellites allowed the identification of a significant subpopulation structure (K?=?3), consistent with an isolation by distance model for P. simonii populations. Additionally, molecular variance analysis revealed that 14.2 % of the variation resided among populations, and 85.8 % could be attributed to variation within populations. These data provide valuable information for natural resource conservation and for optimization of breeding programs in the immediate future.  相似文献   

3.
龙生型花生的遗传多样性   总被引:2,自引:0,他引:2  
龙生型花生(Arachis hypogaea var.hirsute)是中国引进最早、种植最早的花生类型。经过不断地自然选择和人工选择,形成了许多各具特色的地方品种,并逐渐形成了次生中心。本实验对15份龙生型花生资源在植物学性状和品质性状及分子水平上进行了系统研究。结果表明:龙生型花生在植物学性状和品质性状上具有丰富的遗传多样性,在分子水平上差异也较大。变异系数在5.10~34.60之间,多样性指数在1.17~2.04之间,同时两者的变化趋势相反。基于植物学性状和品质性状上的聚类分析在阀值为6.5将龙生型花生分为两大类,一类主要包括广西的品种,另一类包括其它省份的品种;基于AFLP分析的聚类结果在阀值为0.39处分为5类,一类主要包括广西的品种,其它4类包括其它省份的品种。  相似文献   

4.
To determine the genetic diversity and validate the pedigree record of Chinese Guanzhong horse, 67 individuals were genotyped with eight microsatellite markers. In our study, the mean observed and expected heterozygosities were 0.51 and 0.66, respectively. The mean observed number of alleles for the Guanzhong horse was 3.88. Nonetheless, the total value of FST multiloci clearly indicates that about 0.5% of overall genetic variation is due to line founder differences, while differences among individuals are responsible for the remaining 99.5%. In addition, the polymorphic information content (PIC) result showed that five loci (HTG7, HMS7, HMS2, AHT4, and HMS6) were highly polymorphic (PIC?>?0.5) and three loci (HMS3, HTG6, and COR071) were moderate polymorphic (PIC?>?0.25). Genetic distances and cluster analysis showed that the genetic relationship among 67 Guanzhong horse was generally consistent with pedigree recorded. Our results not only evaluated the genetic diversity of Chinese Guanzhong horse, but also suggested that the eight microsatellite markers might be used as subservient markers for parentage verification and individual identification in the Guanzhong horse.  相似文献   

5.
The present study was conducted to assess the genetic diversity, population structure, and relatedness in Indian red jungle fowl (RJF, Gallus gallus murgi) from northern India and three domestic chicken populations (gallus gallus domesticus), maintained at the institute farms, namely White Leghorn (WL), Aseel (AS) and Red Cornish (RC) using 25 microsatellite markers. All the markers were polymorphic, the number of alleles at each locus ranged from five (MCW0111) to forty-three (LEI0212) with an average number of 19 alleles per locus. Across all loci, the mean expected heterozygosity and polymorphic information content were 0.883 and 0.872, respectively. Population-specific alleles were found in each population. A UPGMA dendrogram based on shared allele distances clearly revealed two major clusters among the four populations; cluster I had genotypes from RJF and WL whereas cluster II had AS and RC genotypes. Furthermore, the estimation of population structure was performed to understand how genetic variation is partitioned within and among populations. The maximum ?K value was observed for K = 4 with four identified clusters. Furthermore, factorial analysis clearly showed four clustering; each cluster represented the four types of population used in the study. These results clearly, demonstrate the potential of microsatellite markers in elucidating the genetic diversity, relationships, and population structure analysis in RJF and domestic chicken populations.  相似文献   

6.
花生根部性状的遗传分析   总被引:1,自引:0,他引:1  
利用花生RIL群体,分析了11个花生根部性状的遗传力,估算基因对数及性状间的相互关系,根据偏度系数(g1)和峰度系数(g2)估算控制性状的基因互作情况。结果表明:11个性状都是受多基因控制的数量性状,在RIL群体中基因型间的差异均表现为连续变异和明显的超亲分离。侧根干重的遗传力最高达0.60,其次是侧根鲜重,为0.58,而其他性状的遗传力均较低。控制主根长性状的多基因间存在互作,互作方式为重叠作用;控制主根粗(3cm)性状的基因间也存在一定的重叠作用,但是作用不明显;控制其他性状的基因都存在互作,表现为互补作用,但互补作用的强弱有差异。主根粗(1cm)、主根粗(3cm)、主根干重、主根鲜重、侧根干重和侧根鲜重之间都显著或极显著相关;根体积与主根粗(1cm)、主根粗(3cm)、侧根干重和侧根鲜重显著或极显著相关。  相似文献   

7.
花生成熟花粉的超微结构   总被引:2,自引:0,他引:2  
席湘媛 《云南植物研究》2001,23(2):T001-T002
花生(Arachis hypogaea L.)成熟花粉为二细胞型,具3个萌发沟,少数有4个。外壁呈蜂窝状。花粉壁由覆盖层、基粒棒、外壁内层及内壁构成。线粒体嵴密集、相互平行,脂体被粗面内质网包围。粗面内质网与外核膜相连,亦与线粒体相连。高尔基体甚少。营养核无核仁及染色质,与生殖细胞相连形成雄性生殖单位(male germ unit)。生殖细胞锤形、有壁,见一末端延伸成长尾状(长8μm)。细胞质含核糖体、线粒体、微管,未见体。在有些生殖细胞核内观察到具双层膜、少量嵴及深色内含物的球形结构,其米来源及本质尚不知,有待进一步研究确定。  相似文献   

8.
冀鲁豫花生育成品种的遗传多样性分析   总被引:2,自引:0,他引:2  
以冀鲁豫三省不同地域的41个花生育成品种为材料,利用SSR分子标记结合田间表型鉴定、聚类分析等方法对其遗传多样性进行了研究。结果表明,21对SSR引物对41个花生育成品种进行了扫描,共检测到52个等位变异,每个位点2~4个,平均2.5个,Shannon信息指数变幅为0.21~1.40,平均为0.73,聚类分析显示在阈值为5.54可将供试品种分为3大类群7个亚类。不同品种9个农艺性状变异系数在13.16%~186.49%之间,基于农艺性状的聚类分析结果显示在阈值为5.48时可以将供试品种分为6大类群11个亚类,各大类群间品种的农艺性状表现各具特点。  相似文献   

9.
秦川母牛群体遗传特性的微卫星标记研究   总被引:3,自引:1,他引:3  
为了从DNA分子水平揭示秦川牛群体遗传多态性和群体遗传结构,寻找可用于秦川牛的微卫星标记,本研究选择了12个普通牛(Bos taurus)微卫星标记检测了90头秦川母牛各微卫星位点的遗传变异及多态性。结果表明,在秦川母牛群体中,12个微卫星位点共检测到了247个等位基因,各位点的等位基因数在13(INRA005)~33个(HEL13)之间,平均每个微卫星位点的等位基因数为21个;总有效等位基因数和平均每个位点平均有效等位基因数(Ne)分别分为142.6229和11.8852。各位点平均基因频率取样方差(V(pij))为2.6036×10^-4。12个微卫星位点平均观察杂合度(Ho)和平均期望杂合度(He)在0.7842(INRA005)~0.9775(BM315)和0.7952(BM315)~0.9446(HEL13)之间。12个位点平均多态信息含量(PIC)在0.7653(INRA005)~0.9420(HEL13)之间,平均为0.8965.12个微卫星位点均属于高度多态位点,这表明秦川母牛群体中所检测各微卫星位点具有丰富的遗传多态性,具备较大的选择潜力。12个微卫星位点的平均固定指数(F)为-0.0076,即各位点杂合子的缺陷度不高,即偏离Hardy—Weinberg平衡的程度不大。  相似文献   

10.
尼西鸡遗传多样性微卫星标记分析   总被引:13,自引:0,他引:13  
尼西鸡抗病力强,产蛋性能高,适应高海拔及寒冷的气候条件,是具有独特群体遗传特性的高原地方鸡种。为了对其有效保护和合理利用提供遗传背景资料,筛选了家鸡基因组24条染色体上的33个微卫星标记,对随机选取的50个尼西鸡个体进行多态性检测,共检测到122个等位基因,每个座位平均等位基因数为3·7个。该群体平均多态信息含量和平均杂合度分别为0·5514和0·6350,大染色体较小染色体的微卫星多态性程度高。表明尼西鸡属多态性较丰富的群体。  相似文献   

11.
中国沙皮犬微卫星DNA分析的遗传多样性   总被引:1,自引:0,他引:1  
运用20对微卫星引物对来自中国广东省的92份沙皮犬血液样品(骨嘴型沙皮犬21只,骨肉嘴型沙皮犬29只,肉嘴型沙皮犬42只)进行了遗传背景的检测。结果表明,20个多态性微卫星座位共检测到272个等位基因,平均每个座位为13.6个。中国沙皮犬群体的平均杂合度为0.8259,所有微卫星标记座位的多态信息含量(PIC)在0.5352到0.9226之间,说明中国沙皮犬群体存在较为丰富的遗传多样性。遗传距离和聚类分析结果显示,3种类型沙皮犬之间已产生了一定的遗传分化。上述结果为中国沙皮犬细分为不同的品系以及澄清中国沙皮犬种质资源的混乱状况提供了理论依据。  相似文献   

12.
以85份花生栽培种为材料,分别应用银染法和荧光检测法检测9对SSR引物的扩增产物。比较结果显示,荧光检测法具有灵敏度高、检测结果准确、效率高等优点。聚类分析表明,银染法与荧光检测法分别能够区分74个、82个花生品种,并分别聚成8个、9个类群;荧光检测法的聚类结果虽然反映的品种间遗传多样性较低,但与品种类型、产地及其亲缘关系相关程度更高,表明荧光检测数据更精确、可靠。遗传多样性分析发现,地方品种的遗传多样性指数最高,其次为多粒型育成品种,表明我国地方品种和多粒型育成品种蕴藏了丰富的优异性状,有利于对其挖掘和利用。  相似文献   

13.
Genetic structure of four populations in Castanopsis fargesii Franch. in Fujian Province was studied with microsatellite (SSR) markers. A high level of genetic variation was detected in the populations of C. fargesii by using SSR with A=9.0, Ne=4.8, He=0.65 and the population differentiation coefficient ( Fst ) was only 0.031. The distributions of alleles of all loci were significantly different among the populations of C. fargesii , and the population differentiation could be found according to the distributions of SSR alleles. Some rare alleles in the populations of C. fargesii were revealed by SSR: Fifteen of 54 alleles appeared in one or two populations with lower frequencies; conservation of these rare alleles is of great importance.  相似文献   

14.
Twenty three polymorphic microsatellite markers were developed for citrus plant pathogenic fungus, Colletotrichum gloeosporioides, and were used to analyze genetic diversity and population structure of 163 isolates from four different geographical regions of Ethiopia. These loci produced a total of 118 alleles with an average of 5.13 alleles per microsatellite marker. The polymorphic information content values ranged from 0.104 to 0.597 with an average of 0.371. The average observed heterozygosity across all loci varied from 0.046 to 0.058. The gene diversity among the loci ranged from 0.106 to 0.664. Unweighted Neighbor-joining and population structure analysis grouped these 163 isolates into three major groups. The clusters were not according to the geographic origin of the isolates. Analysis of molecular variance showed 85% of the total variation within populations and only 5% among populations. There was low genetic differentiation in the total populations (FST = 0.049) as evidenced by high level of gene flow estimate (Nm = 4.8 per generation) among populations. The results show that Ethiopian C. gloeosporioides populations are generally characterized by a low level of genetic diversity. The newly developed microsatellite markers were useful in analyzing the genetic diversity and population structure of the C. gloeosporioides populations. Information obtained from this study could be useful as a base to design strategies for better management of leaf and fruit spot disease of citrus in Ethiopia.  相似文献   

15.
In recent years, the population size of Taiwan yellow cattle has drastically declined, even become endangered. A preservation project, Taiwan Yellow Cattle Genetic Preservation Project (TYCGPP), was carried out at the Livestock Research Institute (LRI) Hengchun branch (1988–present). An analysis of intra- and inter- population variability was performed to be the first step to preserve this precious genetic resource. In this work, a total number of 140 individuals selected from the five Taiwan yellow cattle populations were analyzed using 12 microsatellite markers (loci). These markers determined the level of genetic variation within and among populations as well as the phylogenetic structure. The total number of alleles detected (122, 10.28 per locus) and the expected heterozygosity (0.712) indicated that these five populations had a high level of genetic variability. Bayesian cluster analysis showed that the most likely number of groups was 2 (K = 2). Genetic differentiation among clusters was moderate (F ST = 0.095). The result of AMOVA showed that yellow cattle in Taiwan had maintained a high level of within-population genetic differentiation (91%), the remainder being accounted for by differentiation among subpopulations (4%), and by differentiation among regions (5%). The results of STRUCTURE and principal component analysis (PCA) revealed two divergent clusters. The individual unrooted phylogenetic tree showed that some Kinmen yellow cattle in the Hengchun facility (KMHC individuals) were overlapped with Taiwan yellow cattle (TW) and Taiwan yellow cattle Hengchun (HC) populations. Also, they were overlapped with Kinmen × Taiwan (KT) and Kinmen yellow cattle (KM) populations. It is possible that KMHC kept similar phenotypic characteristics and analogous genotypes between TW and KM. A significant inbreeding coefficient (F IS = 0.185; P < 0.01) was detected, suggesting a medium level of inbreeding for yellow cattle in Taiwan. The hypothesis that yellow cattle in Taiwan were derived from two different clusters was also supported by the phylogenetic tree constructed by the UPGMA, indicating that the yellow cattle in Taiwan and in Kinmen should be treated as two different management units. This result will be applied to maintain a good level of genetic variability and rusticity (stress-resistance) and to avoid further inbreeding for yellow cattle population in Taiwan.  相似文献   

16.
用SSR研究栲树群体遗传结构   总被引:22,自引:1,他引:22  
利用微卫星(SSR)分子标记对福建省内4个栲树(Castanopsis fargesii Franch.)群体遗传结构进行了研究。SSR标记揭示了栲树群体丰富的遗传变异:平均等位基因数A=9.0,平均有效等位基因数Ne=4.8,平均期望杂合度He=0.65,而群 具有较低的Fst值(Fst=0.031)。SSR每个位点的等位基因频率分布在栲树群体间都存在显或极显差异,表明根据SSR等位基因频率分布亦能了解各体的分化。SSR标记使栲树群体中一些稀有等位基因得以表现,54个SSR等位基因中有15个等位基因仅出现在1个或2个群体中,且频率较低,在遗传多样性保护中更应注重保护这些稀有的等位变异。  相似文献   

17.
微卫星标记在玉米群体遗传多样性研究中的应用   总被引:1,自引:0,他引:1  
简要综述了近几年利用微卫星(SSR)分子标记技术分析玉米群体遗传多样性过程中的研究进展对研究中混合取样,荧光标记技术,共享数据库等新方法的使用作了阐述.  相似文献   

18.
Corylus mandshurica, also known as pilose hazelnut, is an economically and ecologically important species in China. In this study, ten polymorphic simple sequence repeat (SSR) markers were applied to evaluate the genetic diversity and population structure of 348 C. mandshurica individuals among 12 populations in China. The SSR markers expressed a relatively high level of genetic diversity (Na = 15.3, Ne = 5.6604, I = 1.8853, Ho = 0.6668, and He = 0.7777). According to the coefficient of genetic differentiation (F st = 0.1215), genetic variation within the populations (87.85%) were remarkably higher than among populations (12.15%). The average gene flow (Nm = 1.8080) significantly impacts the genetic structure of C. mandshurica populations. The relatively high gene flow (Nm = 1.8080) among wild C. mandshurica may be caused by wind-pollinated flowers, highly nutritious seeds and self-incompatible mating system. The UPGMA (unweighted pair group method of arithmetic averages) dendrogram was divided into two main clusters. Moreover, the results of STRUCTURE analysis suggested that C. mandshurica populations fell into two main clusters. Comparison of the UPGMA dendrogram and the Bayesian STRUCTURE analysis showed general agreement between the population subdivisions and the genetic relationships among populations of C. mandshurica. Group I accessions were located in Northeast China, while Group II accessions were in North China. It is worth noting that a number of genetically similar populations were located in the same geographic region. The results further showed that there was obvious genetic differentiation among populations from Northeast China to North China. Results from the Mantel test showed a weak but still significant positive correlation between Nei’s genetic distance and geographic distance (km) among populations (r = 0.419, P = 0.005), suggesting that genetic differentiation in the 12 C. mandshurica populations might be related to geographic distance. These data provide comprehensive information for the development of conservation strategies of these valuable hazelnut resources.  相似文献   

19.
利用微卫星标记分析东平湖黄颡鱼的遗传多样性   总被引:11,自引:0,他引:11  
采用27对鲤微卫星引物对山东东平湖黄颡鱼进行全基因组扫描,结果有19对引物能获得稳定的扩增条带,其中有6个微卫星位点具有多态性。对这6个位点的扩增产物进行分析,结果显示:6个位点共检测到22个等位基因,每个位点的等位基因数从2个到6个不等;平均基因纯合率为41.67%,平均多态信息含量(PIC)为0.488,平均杂合度为0.5833。这表明东平湖黄颡鱼种群结构合理,群体遗传多样性较丰富,种质资源处于安全状态。  相似文献   

20.
为研究雷州半岛湖栖鳍虾虎鱼(Gobiopterus lacustris)遗传多样性,对湖栖鳍虾虎鱼雌雄性腺进行转录组测序,采用MISA软件进行微卫星分析,共获得25 452个微卫星标记,其中包含14 708个单碱基重复类型,6 175个2碱基重复类型,3、4、5和6碱基重复类型数目分别为4 223、327、15和4。随机选取50个微卫星位点设计引物,能够扩增出清晰稳定条带的有39对,其中,11个位点表现出不同程度的多态,28个位点呈现单态。利用11个具有多态性的微卫星位点分析湖栖鳍虾虎鱼在廉江市高桥镇红树林保护区、湛江东海岛、雷州市附城镇和雷州市九龙山红树林国家湿地公园4个野生群体中的遗传多样性及遗传结构,11个微卫星位点呈现出不同程度的多态性,等位基因数(Na)2~15,平均等位基因为(6?3.9)个,有效等位基因数(Ne)、平均观测杂合度(Ho)和期望杂合度(He)分别在1.919~2.485、0.343~0.465和0.381~0.483之间,平均多态信息含量(PIC)为0.348~0.465。Hardy-Weinber平衡分析显示,4个群体的大部分位点未偏离平衡。在每个群体中进...  相似文献   

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