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1.
半夏居群遗传分化的同工酶和可溶性蛋白电泳的聚类分析   总被引:2,自引:0,他引:2  
用聚丙烯酰胺凝胶电泳(PAGE)技术分析了安徽产7个半夏(PinelliaternataBreit)居群的4种同工酶和可溶性蛋白谱带。根据其中的PER、EST和可溶性蛋白谱带的分布特征,用Forguson和Aquado&Avise的公式分别计算其谱带的相似性系数和遗传距离,以类平均法(UPGMA)进行了聚类分析。结果表明:半夏居群间表现出一定的遗传分化;鹞落坪半夏与半夏的黄山、九华山、大别山万佛寺居群间的遗传距离较小(D≤0.214),结合形态变异,笔者认为鹞落坪半夏只能是半夏居群中形态上较为特殊的地方宗,而不是一新种;狭叶半夏与其它6个居群的遗传距离较大(D=0.416),是半夏居群中种系分化较为强烈的一个居群。文中还讨论了半夏的遗传分化与形态变异、生境等的相关性。  相似文献   

2.
A powerful approach to address the general factors contributing to ecological speciation is to compare distantly related taxa that inhabit the same selective environments. In this design, similarities among taxa can elucidate general mechanisms of the process whereas differences may uncover specific factors important to the process for individual taxa. Herein, we present evidence of parallel patterns of morphological and behavioral variation among host-associated populations of two species of cynipid gall wasps, Belonocnema treatae and Disholcaspis quercusvirens, that each exhibit a life cycle intimately tied to the same two host plant environments, Quercus geminata and Q. virginiana. Across both gall-former species we find consistent differences in body size and gall morphology associated with host plant use, as well as strong differences in host plant preference, a measure of habitat isolation among populations. These consistent differences among taxa highlight the important role of host plant use in promoting reproductive isolation and morphological variation among herbivorous insect populations–a prerequisite for ecological speciation.  相似文献   

3.
侵染半夏的两种病毒的分离纯化和初步鉴定   总被引:10,自引:0,他引:10  
用自然感染的半夏(Pinelliaternata)为材料,经粗提纯后检查到一种线状病毒和一种球状病毒,用两种方法对担提纯样品中的病毒粒子进行了分离纯化。10%-70%连续甘油梯度80000g离心150分钟获得两条病毒带,经紫外吸收测定均为强的核蛋白吸收峰,病毒粒子检查分别为球状和线状病毒粒子,线状病毒经浓缩收集为均一成份.与芋花叶病毒(Dasheemmosaicvirus,DMV)抗体有强的阳性反应。粗提纯样品经0.8%琼脂糖凝胶电脉分离为一条蛋白带,该条带回收后经紫外吸收测定为核蛋白吸收峰,电镜下检查为均一的球状病毒,以TMV为对照、醋酸铀(UAC)负染后测得该球状病毒(pinelliasphericalvirus1.PsV-1)的大小为31.7nm;戊二醛固定后磷钨酸(PTA)负染测得PsV—1的大小为34.0nm。各组分经SDS-聚丙烯酸胺凝焦电泳分析测得线状病毒和球状病毒的外壳蛋白分子量分别为20KD和28KD。初步确定线状病毒为DMV.球状病毒PsV—1为侵梁天南星科半夏的一种新病毒。  相似文献   

4.
目的:该实验旨在用高效液相色谱法对半夏的生品及其炮制品的指纹图谱进行比较研究,通过半夏指纹图谱主峰的变化寻找半夏炮制前后其主要化学成分的变化。方法:采用75%乙醇(含1%的盐酸)对半夏药材生品及其炮制品进行提取, DiamonsilTM C18(150×4.6 mm,5um)色谱柱,0.1%磷酸溶液—乙腈梯度洗脱,洗脱时间定为50 min,检测波长217 nm,以精氨酸为对照品,对半夏的生品及其炮制品的指纹图谱的主峰数目和峰高进行比较分析。结果:该方法精密度和重复性RSD均小于3%,符合有关规定,半夏炮制后主峰数目发生变化。结论:半夏生品清制和姜制后,75%乙醇(含1%的盐酸)提取液中其所含精氨酸与半夏生品相比均有不同程度的下降,而且指纹图谱的主峰数目也有所变化,说明半夏炮制后其主要化学成分发生变化。  相似文献   

5.
半夏凝集素的分离纯化和在植物中的分布   总被引:1,自引:0,他引:1  
从半夏(Pinellia ternata)块根中,经95%硫酸铵沉淀和固定化猪甲状腺球蛋白柱亲和层析分离得到一种凝集素,称为半夏凝集素(PTL)。凝胶过滤、SDS-PAGE和免疫双扩散鉴定PTL是均一的样品,分子量约44kD,由四个约12kD的亚基组成。PTL主要存在于半夏的块茎中,茎中也有少量存在。  相似文献   

6.
Cytological, morphological, and geographical studies of Epilobium angustifolium in China reveal two partly distinct, partly overlapping entities that are best treated as subspecies. The diploid (n=18) subsp. angustifolium has smaller, triporate pollen grains, typically glabrous stems and leaves, and smaller leaves and flowers, and occurs in colder, more northern areas, and at higher elevations in overlap zones. The tetraploid (n=36) subsp. circumvagum has larger pollen with a mixture of quadriporate pollen grains, pubescent stems and leaves, and larger leaves and flowers, and occurs in warmer parts of southern China and at lower elevations. We report 11 chromosome counts, six diploid and five tetraploid, includingthe first reported tetraploids in Asia.  相似文献   

7.
栗属中国特有种居群的遗传多样性及地域差异   总被引:8,自引:0,他引:8  
Genetic variability in 30 populations of three endemic Castanea (Tourn.) L. species (C. moUissima BI., C. seguinii Dode. and C. henryi (Skan) Rehd. et Wils. ) in China was investigated using isoelectric focusing in thin-layer polyacrylamide slab gels at 20 loci coding for 12 enzyme systems. C. mollissima was found to possess a significant higher value of genetic variability than that of the other two species. The percentage of polymorphic loci (P) and the expected heterozygosity (He) were 90.0% and 0. 311 at the species level, respectively; while P = 84.7 %, He = 0.295 at the population level. Comparison of the population genetic variability of C. mollissima in three regions of China, the populations from the Yangtze River valley showed a markedly higher mean expected gene heterozygosity. The results provided additional evidence that the Yangtze River valley, particularly in Shennongjia area, was the center of the genetic diversity of C. moUissima. Genetic relationships among populations and species were assessed by Nei genetic identity (I) and standard genetic distance (D), suggesting that C. mollissima and C. seguinii have a closer relationship, and genetic distances were correlated with geographical distances among populations. Genetic differentiation between populations in C. mollissima, C. seguinii and C. henryi was 7.5%, 10.9% and 22.1%, respectively, and the gene flow rate (Nm) was 3.20, 2.05 and 0.88 respectively. The study provides useful imfonnation for understanding of the origin and evolutionary events in genus Castanea and planning an effective conservation strategy.  相似文献   

8.
三叶半夏叶片一步成苗离体培养技术   总被引:2,自引:2,他引:2  
罗成科  彭正松  蔡鹏   《广西植物》2007,27(2):260-264
以药用植物三叶半夏叶片为材料,通过比较直接和间接器官发生两种途径,建立了半夏一步成苗的快速繁殖技术体系。结果表明,经过愈伤组织阶段的一步成苗培养基为MS+0.5mg/L2,4-D+1.0mg/LKT,90d左右方可得到再生植株,植株分化率为74%,每个外植体上分化的块茎数为5.61±1.04。附加NAA与BA两种激素对一步成苗培养基进行优化,筛选出一步成苗最佳培养基MS+0.5mg/LNAA+0.5mg/LBA,60d后就可直接发育成完整植株,植株分化率为76%,每个外植体上分化的块茎数高达9.97±0·81,对这种培养基上的再生小植株进行移栽,1个月后,移栽成活率达100%。  相似文献   

9.
为了解亚热带地区常绿阔叶林木本植物一级根养分元素变化规律,基于根序法对福建省建瓯市万木林自然保护区天然常绿阔叶林群落的89种树种一级根进行碳、氮浓度测定.结果表明,89种树种一级根的C、N质量浓度分别为433.9和13.7 mg/g,C:N为36.7,变异系数分别为6.4%、39.2%和39.9%;一级根C浓度在叶片习...  相似文献   

10.
半夏凝集素(PTL)可与甘露聚糖结合。本文以PTL与~(125)I标记的甘露聚糖的结合活性为指标,观察了一些金属离子对PTL的糖结合活性的影响,井对PTL的糖结合专一性作了较系统的研究。结果表明常见的金属离子或EDTA对其糖结合活性无显著影响,但K~+可明显增加PTL的糖结合活性。大多数单糖,二糖不抑制PTL与甘露聚糖的结合,但一些疏水配基形成的糖苷可产生显著的抑制效应。PTL专一与高甘露糖型糖链结合。  相似文献   

11.
通过对柴河林业局头道林场一块8年生的落叶松人工林优势种群的当年生的生长节律与生物量的研究发现:优势林分的当年生枝及顶枝的生长较常规林分高峰期多、高峰期持续时间长和生长量大的优点和不同;生物量的分配的研究结果也说明优势林分的树干生物量积累的比重较常规林分高,证明了该罕见优势林分速生原因的内质性,是一个难得的优良种源。  相似文献   

12.
应用微卫星多态分析四个鲤鱼群体的遗传多样性   总被引:27,自引:1,他引:27  
选择12个斑马鱼功能基因的微卫星标记和12个鲤鱼微卫星标记,检测黑龙江鲤(Cyprinus carpiohaematopterusTemminck et Schlegel)、散鳞镜鲤(C.carpio)、荷包红鲤抗寒品系(C.carpiovar.wuyuanensis)、松浦鲤(C.carpioSongpu carp)的群体遗传多样性。共检测到3882个扩增片段,长度为126~489bp,在群体间扩增出1~5个等位基因不等,共计59个等位基因,平均等位基因2.46个。数据经PHYLIP V3.6软件估算和MEGA3软件作图,确立4个群体间的亲缘关系。并应用Bootstrap检验估计系统树中节点的自引导值,并进行了系统发生分析。结果表明①4个群体检测的有效等位基因数都在55个以上,平均观测杂合度为0.36~0.43,平均期望杂合度为0.49~0.53,平均多态信息含量为0.21~0.25,说明这几个群体多态性属于中度偏高水平,遗传多样性较高;②群体间相似系数都在0.84以上,遗传距离较近,为0.067~0.170,与前人研究结果一致。聚类分析显示,松浦鲤与散鳞镜鲤亲缘关系最近,荷包红鲤抗寒品系与它们的亲缘关系较黑龙江鲤更近;③在3个斑马鱼功能基因相关的微卫星位点上,黑龙江鲤缺失特异扩增条带,这可能与几种鱼类的育成史有关。  相似文献   

13.
分离生态变化中的物种相互作用组分   总被引:5,自引:2,他引:5  
本文用描述群落的最小剩余码的平均码长L(S)测度群落总复杂性,用Renyi熵测度非组织复杂性,并将它们之差△(S)作为组织复杂性或群落结构复杂性的测度,提出了一个测度群落内种间相互作用的指标,以有关生物群落结构组建的理论及约束典型排序技术;典型对应分析CCA和测余分析RA为基础,发展一种包括环境,空间格局和物种相互作用三方面因素的植物群落数量分析方法,并在种多度数据的变化中分离出这几个方面的变化。  相似文献   

14.
Yao JH  Zhao XY  Liao ZH  Lin J  Chen ZH  Chen F  Song J  Sun XF  Tang KX 《Cell research》2003,13(4):301-308
The full-length cDNA of Pinellia ternata agglutinin (PTA) was cloned from inflorescences using RACE-PCR. Through comparative analysis of PTA gene (pta) and its deduced amino acid sequence with those of other Araceae species, pta was found to encode a precursor lectin with signal peptide and to have extensive homology with those of other Araceae species. PTA was a heterotetrameric mannose-binding lectin with three mannose-binding boxes like lectins from other Araceae and Amaryllidaceae species. Southern blot analysis of the genomic DNA revealed that pta belonged to a low-copy gene family. Northern blot analysis demonstrated that pta constitutively expressed in various plant tissues including root, leaf, stem and inflorescence. The pta cDNA sequence encoding for mature PTA protein was cloned into pET-32a plasmid and the resulting plasmid, pET-32a-PTA containing Trx-PTA fusion protein, was investigated for the expression in E. coli BL21. SDS-PAGE gel analysis showed that the Trx-PTA fusion protein was successfully expressed in E. coli BL21 when induced by IPTG. Artificial diet assay revealed that PTA fusion protein had significant levels of resistance against peach potato aphids when incorporated into artificial diet at 0.1% (w/v). The cloning of the pta gene will enable us to further test its effect in depth on aphids by transferring the gene into crop plants.  相似文献   

15.
半夏的繁殖生物学研究   总被引:26,自引:0,他引:26  
对“泰半夏”(Pinelliaternata(Thunb.)Breit.)的块茎和珠芽栽培观察结果表明:(1)不同繁殖体的叶形和珠芽所发生的变化与实验用的播种材料有关,珠芽发生频率与叶形变化呈正相关;(2)半夏倒苗既是对不利环境条件的一种适应,也是一种有效的无性繁殖方式;(3)半夏有性繁殖是属于同株异花传粉类型,但与无性繁殖相比,有性繁殖在种质繁衍上仅起着次要作用。  相似文献   

16.
马尾松天然群体同工酶遗传变异   总被引:15,自引:0,他引:15  
黄启强  王莲辉 《遗传学报》1995,22(2):142-151
6个马尾松天然群体同工酶分析结果表明:马尾松群体具有较丰富的遗传变异,其多态位点百分率(P)=76.2%;等位基因平均数(Na)=2.39;有效等位基因平均数(Ne)=1.62,平均杂合率(He)=0.273。但群体间遗传分化极小,基因分化系数(G_(ST))=0.0172,遗传距离(D)=0.011±0.005。总遗传变异中,约2%来自群体间,而约98%的遗传变异存在于群体内的个体,并且其变异又主要来源于1/3的基因位点。马尾松群体近似于随机交配群体,绝大多数位点处于平衡状况,但也有约1/3的位点并非随机交配,存在不同程度的近交。  相似文献   

17.
黄牡丹八个居群的Giemsa C-带比较研究   总被引:10,自引:1,他引:10  
应用BSG方法对黄牡丹(Paeonia delavayi var.lutea)8个居群的Giemsa C-带进行了比较研究。8个居群的所有染色体都在着丝点附近显示出了C-带,所有染色体的长臂上都没有显示C-带,而短臂上的C-带数量和位置在居群之间表现出了一定的差异。花甸凡居群手第二、第三、第四和第五对染色体显示端带;卓干山居群的第一、第三、第四和第五对染色体的短臂上没有显示C-带。在所研究的8个居  相似文献   

18.
A measure of difference between populations for a trait should reflect not only the differences in the relative frequencies of the trait states but also the trait differences between the states. Common approaches to measuring differences between populations rely on distance, probability, or variance concepts. To overcome conceptual problems of these approaches, a new difference measure Δ is presented that is based on both frequency and trait differences. For two populations, Δ expresses the degree to which the frequency distribution of the trait states within one population must be transformed in order to make it match the distribution in the other population. This is done by shifting the relative frequency excesses of trait states to other trait states of deficient frequency, where shifts occur between as similar states as possible. Δ equals the minimum sum of the shifted frequencies weighted by the respective trait differences. Its bounds are functions of the difference measure d0, which considers only differences in relative frequency. The computer program DeltaS applies an algorithm from operations research to calculate Δ. The effect of including trait differences is demonstrated by the topological differences observed between Δ‐ and d0‐dendrograms constructed from microsatellite allele frequencies in four riparian stands of black poplar (Populus nigra), where the trait difference between two alleles equals the difference in numbers of tandem repeats. Δ is applicable to all traits for which trait differences are measurable, and it is shown to have elementary linearity properties that considerably simplify its interpretation.  相似文献   

19.
物种丰富度垂直分布格局及影响机制   总被引:1,自引:0,他引:1  
物种丰富度分布格局是一定地域内物种丰富度沿三维空间的立体分布,包括物种丰富度在经度、纬度和垂直梯度(海拔高度和海水深度)三个维度上的空间分异。近年来物种多样性的垂直分布格局与机制研究得到了生物地理学家和生态学家的重视。物种丰富度的垂直分布格局存在多种类型,但随海拔增加而物种数减少的单调递减模型和中海拔物种丰富度最高的单峰模型较为常见。目前在机制研究中验证较多的是气候稳定性、生物因子(种间相互作用)、能量、生境异质性、干扰、进化时间、物种分化速率、面积、中域效应(mid-domain effect)、生态位保守性(niche conservatism)等假说和机制。物种丰富度的分布格局是多方面因素综合作用的结果;由于地理、地形、气候、地质演化历史、物种库和进化历史、物种分化速率、干扰等差异,在不同地区存在着特别的物种丰富度空间分布格局和机制;处于同一地区的不同类群的物种也因进化扩散历史和生态适应能力不同而呈现多样化的分布格局。因此,对不同地区和类群的物种丰富度格局和机制进行研究应具体分析后才能得到可信结论。  相似文献   

20.
Size homoplasy was analyzed at microsatellite loci by sequencing electromorphs, that is, variants of the same size (base pairs). This study was conducted using five interrupted and/or compound loci in three invertebrate species, the honey bee Apis mellifera, the bumble bee Bombus terrestris, and the freshwater snail Bulinus truncatus. The 15 electromorphs sequenced turned out to hide 31 alleles (i.e., variants identical in sequence). Variation in the amount of size homoplasy was detected among electromorphs and loci. From one to seven alleles were detected per electromorph, and one locus did not show any size homoplasy in both bee species. The amount of size homoplasy was related to the sequencing effort, since the number of alleles was correlated with the number of copies of electromorphs sequenced, but also with the molecular structure of the core sequence at each locus. Size homoplasy within populations was detected only three times, meaning that size homoplasy was detected mostly among populations. We analyzed population structure, estimating F st and a genetic distance, based on either electromorphs or alleles. Whereas little difference was found in A. mellifera, uncovering size homoplasy led to a more marked population structure in B. terrestris and B. truncatus. We also showed in A. mellifera that the detection of size homoplasy may alter phylogenetic reconstructions. Received: 21 July 1997 / Accepted: 29 January 1998  相似文献   

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