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131.
The effect of volcanism on postglacial migration and seed dispersal. A case study in southern South America 总被引:1,自引:0,他引:1
During the Quaternary, southern South American temperate forests were confined to small and isolated refugia. Recolonization
could be related not only with location of refugia but also with postglacial phenomena like volcanism, which could have interrupted
the expansion of the forests. The aim of this study was to analyze the local effect of volcanism during the postglacial migration
of Nothofagus nervosa in a particular region of Argentina were convergence of two migratory routes was suggested. The main question is whether
admixture occurred or not and if the current populations are connected by pollen or seed gene flow. Two populations separated
by a 3-km-width lava flow were sampled. Buds from 30 individuals of each of the two populations and from a total of 142 juveniles
were analyzed. Genetic variation was detected through maternally inherited chloroplast deoxyribonucleic acid (cpDNA; polymerase
chain reaction restriction fragment length polymorphisms of two fragments) and nuclear markers like isozymes (six loci) and
simple sequence repeats (three loci). Population genetic parameters were estimated and the existence of a genetic structure
was tested with an analysis of molecular variance. Historical gene flow was estimated through the indirect method of the genetic
differentiation (F
ST). Chloroplast DNA revealed a total genetic differentiation between the two populations indicating completely isolation respecting
seed gene flow. On the contrary, the degree of genetic differentiation for the nuclear markers was significantly lower, and
moderate levels of historical gene flow through pollen were inferred. The results suggest that in this area, volcanism has
played an important local role during the expansion of N. nervosa maintaining these two populations separated.
Communicated by A. Kremer 相似文献
132.
用SSR标记鉴定大豆杂交组合F1的方法研究 总被引:10,自引:0,他引:10
为建立鉴定大豆杂种的方法,采用亲本间有多态性的3对SSR引物,对148个耐盐与盐敏感大豆品种正反交F1植株进行分子鉴定,结果表明,有81.8%的F1为真杂种,且3对多态性SSR引物检测结果一致;在亲本基因型纯合的情况下,采用1对在亲本间有多态性的SSR引物即可对F1真伪进行准确判断;亲本间分子量差异大的SSR位点可用高浓度琼脂糖电泳进行快速鉴定。利用该方法对2007年参加国家大豆区试的大豆杂交种品系H02—286的50粒种子进行纯度鉴定,进一步验证了SSR标记检测杂种真伪的可行性。 相似文献
133.
应用SSR标记分析大豆种质资源的遗传多样性 总被引:8,自引:4,他引:4
利用SSR分子标记分析了119个大豆品种的遗传多样性,结果表明:30对SSR引物在119份材料中共检测出159个等位变异,平均每对引物检测到5.30个等位变异;河北省农家品种中平均每对引物检测到5.17个等住变异,育成品种4.87个,省外品种4.93个,表明地方品种的遗传多样性高于育成品种。河北省农家品种、育成品种和省外育成品种依据SSR数据获得的品种间相似系数总体平均值相近,分别为0.698、0.698、0.672,但河北省农家品种较育成品种具有较大的变化幅度。119个品种可被划分为3个类群,在一定程度上能把育成品种和农家品种分开,并反映了一定的品种地域来源。 相似文献
134.
Microsatellite loci were identified from Cornus kousa'National'. Primer pairs for 86 loci were developed and of these, eight were optimized and screened using genomic DNA from 22 kousa cultivars. All optimized loci were polymorphic and the number of alleles per locus ranged from three to 17. Observed heterozygosity ranged from 0 to 0.3 and expected heterozygosity ranged from 0.38 to 0.91. These microsatellites will be useful in population studies, and a breeding programme for cultivar development of Cornus species. 相似文献
135.
Atriplex nummularia is a polyploid Australian saltbush which has been identified as a suitable species for use in the rehabilitation of agricultural land affected by salinity. We isolated 12 polymorphic loci for a preliminary assessment of genetic variability and structure within the species as a basis for a breeding programme. Preliminary screening of loci in 40 individuals from two populations revealed multibanded genotypes consisting of up to seven alleles in a single individual, with up to 29 alleles observed at a single locus. The multibanded patterns are consistent with the polyploid status of this species. 相似文献
136.
Ten microsatellite loci were isolated and characterized for Callicarpa subpubescens (Verbenaceae), an endemic tree species of the Bonin Islands. The observed number of alleles at each locus ranged from two to eight with an average of 4.9, and the expected heterozygosity ranged from 0.238 to 0.690 with an average of 0.483. All 10 loci were screened in cross-amplification tests for two other endemic Callicarpa species that also inhabit the Bonin Islands. All loci were successfully amplified in these species. 相似文献
137.
Crawford NG Zaldívar-Rae J Hagen C Schable A Rosenblum EB Graves JA Reeder TW Ritchie MG Glenn TC 《Molecular ecology resources》2008,8(1):219-223
We describe polymerase chain reaction primers and amplification conditions for 13 microsatellite DNA loci isolated from two bisexual species of whiptail lizards Aspidoscelis costata huico and Aspidoscelis inornata. Primers were tested on either 16 or 48 individuals of A. c. huico and/or 26 individuals of A. inornata. Ten of the 13 primers were also tested against a panel of 31 additional whiptail taxa. We detected three to nine alleles per locus in A. c. huico and four to 19 alleles per locus in A. inornata, with observed heterozygosity ranging from 0.60 to 0.87 and from 0.15 to 1.00, respectively. These primers will be an important resource for surveys of genetic variation in these lizards. 相似文献
138.
Shamblin BM Faircloth BC Josserand SA Nelson CD Nairn CJ 《Molecular ecology resources》2008,8(6):1354-1356
We describe polymerase chain reaction primer pairs and reaction conditions for amplification of 15 microsatellite loci from eastern hemlock (Tsuga canadensis). The primers were tested on 23 individuals from a natural population in southwestern North Carolina, USA. These primers yielded an average of 5.9 alleles per locus (range of 2-14), an average observed heterozygosity of 0.45 (range 0.14-0.73), and an average polymorphic information content of 0.54 (range 0.28-0.86). In addition, eight of the primer pairs were found to amplify microsatellite loci in one or more additional species of Tsuga. 相似文献
139.
Pereira MF Bandeira LF Blanco AJ Ciampi AY Coelho AS 《Molecular ecology resources》2008,8(6):1329-1331
Annona crassiflora Mart. (Annonaceae) is a native fruit species of the region of Brazilian Cerrado with a high agronomic potential, although without any traces of domestication. A set of 10 microsatellite primer pairs was developed from an enriched genome library (TC13). An average of 19.3 alleles per locus was detected. Observed heterozygosity estimates were consistently lower than those obtained for gene diversity, evidencing a departure from Hardy-Weinberg expected proportions. The reported set of markers showed to be highly informative and constitutes a powerful tool for the development of genetic characterization studies in A. crassiflora. 相似文献
140.
We have developed eight high-quality microsatellite DNA loci for the saltmarsh sharp-tailed sparrow and one additional locus with evidence of null alleles. In a sample of 250-350 individuals, the average number of alleles per locus was 14.7 and average observed heterozygosity was 0.80. These loci were tested in three additional species of emberizid sparrows, indicating that more than half of the loci could be useful in other sparrows. 相似文献