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无瓣海桑引种种群遗传多样性的ISSR分析 总被引：9，自引：0，他引：9
采用ISSR（inter—simple sequence repeat）分子标记技术对采白海南和深圳的2个无瓣海桑Sonneratia a petala种群共45个个体进行了遗传变异分析。11个ISSR引物共扩增出196条带，其中128条具多态性，多态位点百分率为65．31％。在种群水平上多态位点百分率为48．47％。Nei的基因多样性、Shannon信息指数在物种水平上分别为0．1556和0．2441，在种群水平上分别为0．1403和0．2142。无瓣海桑从海南引种到深圳后，遗传多样性水平有所降低。依据Nei的基因分化系数和AMOVA（analysis of molecular variance）分析结果，无瓣海桑种群间发生了一定的遗传分化，但绝大多数遗传变异发生在种群内的个体间。种群间遗传一致度为0．9645，遗传距离为0．0362。UPGMA聚类分析表明，来自同一种群的个体一般都聚在一起。 相似文献
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采用不连续垂直板聚丙烯酰胺凝胶电泳技术，对广西北海、福建漳港和江苏启东3个西施舌自然群体的7个等位酶12个位点进行检测分析。结果表明，西施舌群体的遗传多样性较高，平均每位点等位基因数目（A）范围为1．5833—2．0000、平均每位点有效等位基因数目（Ae）范围为1．2850—1．5373、多态位点百分数（P）为33．33％、观察杂合度（Hc）为0．2389-0．3083、期望杂合度（He）为0．1496—0．2041之间。西施舌群体间有一定的遗传分化，遗传分化系数（FST）为0．0719，福建漳港群体与广西北海群体之间的FST为0．0413，但福建漳港群体和广西北海群体与江苏启东群体之间的FST为0．0505。 相似文献
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用9对微卫星引物对尼罗罗非鱼Oreochromis niloticus、奥利亚罗非鱼O.aureus和红罗非鱼O.sp.群体的遗传变异进行了比较研究。在3个群体109个个体中共检测到60个等位基因,3个群体的平均等位基因数分别为4.11、1.33和3.44,平均观测杂合度分别为0.528、0.056和0.491,平均期望杂合度分别为0.644、0.091和0.526,平均多态信息含量分别为0.580、0.077和0.466。杂合子偏离度D值分别为0.148、0.222和0.044,表明3个罗非鱼群体存在不同程度的杂合子缺失。卡方检验表明3个群体的大部分位点偏离Hardy-Weinberg平衡,存在遗传漂变现象。群体间遗传分化显著(遗传分化指数FST在0.329到0.656之间,P<0.01)。尼罗罗非鱼和红罗非鱼群体间的遗传距离最小(0.47)。上述分析表明,尼罗罗非鱼的遗传多样性最高,奥利亚罗非鱼的遗传多样性最低,群体间分化显著。表明尼罗罗非鱼和红罗非鱼尚具有一定的选育潜力,而奥利亚罗非鱼遗传多样性低,不利于选择育种,需要引进新的种群。 相似文献
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应用17个EST-SSR位点分析表明,马氏珠母贝印度种群和三亚种群的平均FST值为0.486,两个种群的分化程度高;三亚种群的等位基因数为1—6,有效等位基因数为1.0—3.3;印度种群的等位基因数为2—7,有效等位基因数为1.1—3.3;三亚种群和印度种群的平均有效等位基因数分别是1.8和1.9;三亚种群和印度种群的等位基因丰度分别为3.16和3.39;印度种群无论是期望杂合度(HE)还是观察杂合度(HO)都高于三亚种群,印度种群的期望杂合度和观察杂合度分别是0.42和0.16;三亚种群的期望杂合度和观察杂合度分别是0.38和0.15;三亚种群与印度种群的Nei’s遗传距离为1.119。两个种群都保持了中等水平遗传多样性。由于两个种群高度的遗传分化和保持丰富的遗传多样性为开展两个种群间杂交及获得杂种优势奠定了基础。 相似文献
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为探究不同地理条件下斑节对虾天然群体的遗传多样性和遗传分化水平, 选用14对简单重复序列(simple sequence repeat, SSR)特异引物对广东湛江、海南三亚、海南琼海的斑节对虾天然群体共计90尾个体进行微卫星标记分析, 每对引物检测出的等位基因数为2~4不等, 平均2.7。3个群体(湛江、三亚、琼海)平均有效等位基因分别为1.9081、1.9715和2.0185, 平均多态信息含量分别为0.3864、0.3926和0.4078, 总的平均期望杂合度(0.4605 )明显高于观测杂合度(0.4046), 表明3个群体遗传多样性水平为中等, 且存在杂合度缺失的现象。种群分化指数和遗传距离分析表明, 在不同群体间已产生了遗传分化, 但是分化较小; 三亚群体和琼海群体之间的亲缘关系最近, 而与湛江群体的亲缘关系最远。分子方差分析表明, 群体间的遗传变异指数为8%, 群体内个体间的遗传变异指数为92%, 基因分化主要发生在群体内, 而不是群体之间。 相似文献
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采用微卫星位点对凡纳滨对虾的海南群体（进口亲虾繁育的第1世代：G1）、山东和饶平群体（G2）、湛江2和湛江3群体（G3）、湛江1和上海群体（G4）共4个世代7个养殖群体的遗传多样性进行了分析。从21对微卫星引物中筛选出12对有效扩增引物，对7个群体共280个个体进行扩增，得到10个多态位点，共获得等位基因数63个。各位点的等位基因数在2-15个之间，各群体的平均等位基因数在4．70—5．80之间。平均观测（期望）杂合度在0.36—0．43（0．53—0．65）之间。杂合子偏离指数（D）为负值，表明存在杂合子缺失现象。对7个群体、10个多态位点进行Hardy—Weinberng平衡检测，共有54个偏离平衡。对7个群体间的遗传分化水平进行检测，得到近交系数FIS在9个多态位点均为正值，两两群体间的固定指数FST值在0．149-O．375之间。FST显著性检验表明，各群体之间的遗传分化极显著（P〈0．01）。分子方差分析结果显示，大部分遗传变异（72．17％）来自于群体内，来自于群体间的遗传变异（27．83％）较小。凡纳滨对虾不同世代间遗传变异大，随着繁育世代的增加，遗传多样性降低。 相似文献
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真鲷（Pagrus major）是中国沿岸海域重要的经济种类，增殖放流作为修复真鲷渔业资源、恢复自然群体的方法，现已在中国被广泛地应用。然而，将大量人工繁育的苗种投入自然海域中，可能会对自然群体造成一定程度的遗传学影响。因此，在开展真鲷增殖放流的同时，应进行遗传监测。本研究使用7对真鲷微卫星标记，对2017年于防城港沿岸海域开展的真鲷增殖放流进行遗传监测，对比分析了真鲷亲体、放流真鲷苗种以及放流后混合群体的遗传多样性。研究结果表明，真鲷亲本群体与真鲷放流群体的等位基因丰度（13.525 3，16.428 6）和期望杂合度（0.792 7，0.814 5）没有明显的差异，表明在苗种繁育过程中，没有出现遗传多样性丢失的现象。真鲷放流群体和放流后混合群体的期望杂合度（0.814 5，0.822 8）、等位基因丰度（16.428 6，16.755 5）相似，表明真鲷放流群体和放流后混合群体处于相同的遗传多样性水平。3个群体的多态信息含量为0.768 8~0.805 5，表明3个群体均具有较高的遗传多样性。群体间遗传分化指数（0.016 667）和遗传距离（0.265 375~0.301 915）的结果显示群体间的遗传分化微弱，未形成明显的遗传分化。因此，可认为本研究中真鲷增殖放流未对放流后混合群体造成明显的遗传学影响。本研究为今后真鲷增殖放流遗传监测提供了理论参考依据。 相似文献
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LiZhenji ZhengWenjiao YangZhiwei LinYiming LinPeng 《海洋通报(英文版)》2003,5(2):40-53
The community characteristics of mangroves in the Futian Nature Reserve,Shenzhen, China are given based on surveying of 33 quadrats in 4 transects which stretch from the higher tidal zone to the lower tidal zone. The results show that there are 6 community types in this area: Kandelia candel association, Avicennia marina association, A egiceras corniculatum association, Kandelia candel Aegiceras corniculatum association,degiceras corniculatum Kandelia candel association and Acanthus ilicifolius association.Kandelia candel, degiceras corniculatum and dvicennia marina dominate the typicalquadrats. Kandelia candel can be seen at almost all quadrats, Aegiceras corniculatumdistributes mostly toward the estuary and the higher tidal zone, Avicennia marina distributesmostly toward the bay and the lower tidal zone, Bruguiera gymnorrhiza occasionally occurs toward the Estuary with one or several individuals, Acanthus ilicifolius was common towardthe higher tidal zone, as an accompanying species, Derris trifoliata was common in manymature ouadrats. Totallv. 6 snecies of man~rove plants and 3 soecies of semi-mangrove plants appear in this research area. From the higher tidal zone to the lower tidal zone, the average diameter and basal area of mangrove trees increase gradually. According to the results, the dvicennia marina dominates in average diameter and basal area, and the degicerascorniculatum trees are on the contrary. From the transect ! to the transect 4, the importance value ot dvicennia marina, Bruguiera gymnorrhiza and Kandelia candel decreases, and degiceras corniculatum increases. In this area, the Kandelia candel population and Ae giceras corniculatum population are developing populations with many seedlings and saplings, but the Avicennia marina population is in a mature stage with few seedlings and not so many total individuals. According to this research, we suppose that Aegiceras corniculatum should be developed toward the estuary and the dvicennia marina association should be protected. 相似文献
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As a commercially important fisheries resource in East Asia, the Chinese surf clam Mactra chinensis has experienced severe population declines in the past decades, probably due to over‐exploitation. To provide scientific bases for fisheries management and artificial breeding, we investigated genetic variation and population structure of Mactra chinensis in Northern China using microsatellites. Samples collected from eight localities throughout natural habitats of the species in Northern China were genotyped. Nine microsatellites revealed high allelic diversity with 14–36 alleles per locus. Observed and expected heterozygosity varied from 0.593 to 0.945 and from 0.638 to 0.958, respectively. Pairwise FST values indicated that all population pairs had small but significant genetic differentiation. A Mantel test showed statistically significant correlations between genetic distance and geographical distance, indicating that genetic differentiation of the Chinese surf clam conformed to a pattern of isolation‐by‐distance. Cluster analysis using neighbor‐joining separated the eight populations into three groups. The three areas of low gene flow identified by barrier analysis corresponded with local oceanographic features, suggesting that marine currents and peninsulas play an important role in population structuring of this species. 相似文献
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马氏珠母贝是重要的海水养殖贝类, 为了探究繁育亲本及其子代的遗传结构和关系, 本研究运用多元性形态学和SNP标记对马氏珠母贝母本深圳群体、父本海南群体和其杂交子代F1的外部形态和分子遗传结构进行分析。结果发现, 3个群体的综合判别率为72%, F1和母本群体的形态差异最小, 父本群体与母本、F1的形态差异较大。采用HRM法 (high resolution melting) 应用4个SNP位点对这3个群体进行分型, 3个群体的平均观测杂合度Ho和期望杂合度He分别为0.2110~0.2879和0.3317~0.4685, F1的杂合度高于两个亲本; 平均多态信息含量PIC值为0.2643~0.3556, 呈现中等程度遗传多样性。F1与母本之间的基因流Nm最大(7.7701), 遗传距离最小(0.0546), 亲缘关系最近; 两个亲本之间的Nm最小(1.9662), 遗传距离最大(0.1759)。rs8位点可以判别两个亲本群体, 可作为特异性的标记。该结果可以为马氏珠母贝群体遗传结构鉴别、育种群体管理提供指导。 相似文献
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实验选取的7个杂色鲍(Haliotis diversicolor)养殖群体分别来自广东汕头、汕尾、惠东、湛江和徐闻,深圳野生驯养,利用7对微卫星引物对上述群体进行了遗传多样性和群体遗传结构的分析。结果显示:7个位点产生的等位基因数从7～13个不等,共检测到68个等位基因,平均每个位点的等位基因数为9.71个。有效等位基因数的范围为3.8～8.1,平均观测杂合度范围为0.422～0.906,平均期望杂合度范围为0.748～0.917。7个群体的多态信息含量变化范围为0.657～0.883,PIC值均在0.500以上,表现为高度多态性。与两个野生驯养的养殖群体相比,其他5个养殖群体均存在不同程度的遗传多样性降低。AMOVA分析显示,4.79%的遗传变异来自于群体之间,95.21%的变异来自于群体内的个体之间。研究表明,广东沿岸的杂色鲍具有较高的遗传多样性水平,7个群体之间呈现一定的遗传分化。 相似文献
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The small yellow croaker (Larimichthys polyactis) belongs to the family Sciaenidae, which is an offshore warm fish species and widely distributed in the western Pacific. In this study, the variation of genetic diversity and genetic differentiation among L. polyactis populations was analyzed by mitochondrial DNA control region. A total of 110 polymorphic sites were checked, which defined 134 haplotypes. High level of haplotype diversity (h=0.993±0.002) was detected in the examined range. Population genetic structure analyse (analysis of molecular variance, Fst) showed there were high gene flow among L. polyactis populations. The result showed that there were relatively high genetic diversity and low genetic differentiation among the Yellow Sea and the East China Sea populations, which can be attributed to diverse habitats, wide distribution range and high mutation rate of control region. Using phylogenetic methods, coalescent analyses (neutrality tests, mismatch distribution analysis, Bayesian skyline analyses) and molecular dating interpreted in conjunction with paleoclimatic and physiographic evidence, we inferred that the genetic make-up of extant populations of L. polyactis was shaped by Pleistocene environmental impacts on the historical demography of this species. Besides, relatively constant genetic diversity and larger effective population size were detected in recent L. polyactis population. The result showed that the fishing policy certainly, such as the summer closed fishing, played a role in protecting resources of L. polyactis. This study can offer a wealth of biological novelties which indicates genetic structure of L. polyactis population and provides the foundation for resources protection and policy setting. 相似文献
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采用聚丙稀酰胺凝胶电泳技术对福建平潭岛、浙江象山港、江苏海州湾和辽宁辽东湾4个海区菲律宾蛤仔(Ruditapes philippinarum)野生群体的生化遗传特征进行了分析.结果表明,菲律宾蛤仔4个群体的多态位点比例为62.5%～75.0%,平均杂合度观测值在0.274 3～0.338 7之间,与平均杂合度期望值相近;平均有效等位基因数在1.489 1～1.632 5之间,遗传变异水平较高;杂合子缺失不显著.比较群体间的遗传分化指数和群体每代迁移数发现,平潭岛、象山港和海州湾3个群体间的遗传分化不显著,而辽东湾群体与3个群体间出现遗传差异.聚类分析同样表明,平潭岛群体首先与象山港群体聚类,再与海州湾群体相聚,最后与辽东湾群体相汇.讨论了杂合子缺失不显著原因和群体间遗传分化机制. 相似文献