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1.
Candidia barbata is an endemic cyprinid fish in Taiwan and suffers habitat destruction caused by human overexploitation. In this study, a
total of 14 polymorphic microsatellite loci from C. barbata were isolated and characterized using an optimized protocol to construct a microsatellite-enriched genomic library. The analysis
of variability was performed in 30 specimens of Taiwan. The mean number of alleles across loci was 4.92 ± 1.44. The levels
of expected and observed heterozygosities varied from 0.1266 to 0.5079, and from 0.0667 to 0.9667, respectively. Frequencies
of null alleles of the 14 loci are not significantly greater than zero. No linkage disequilibrium was detected between loci
in either population. 相似文献
2.
Mirjam S. van de Vliet Onno E. Diekmann Ester T. A. Serrão Pedro Beja 《Conservation Genetics》2009,10(4):993-996
Nine highly polymorphic microsatellite markers were isolated and characterized for the Western Spadefoot, Pelobates cultripes. Remarkably, for this amphibian species high numbers of microsatellites were found as part of larger repeat containing regions,
making primer design difficult. For nine loci, primers were designed successfully and genotyping of individuals was reliable
and consistent. Number of alleles and heterozygosity for these loci ranged from 9 to 34 and from 0.72 to 0.94, respectively.
The high levels of polymorphism revealed by our developed loci should provide insight into population genetic structure and
levels of dispersal for this typical Mediterranean temporary pond-breeding amphibian. 相似文献
3.
QTL analysis of potato tuberization 总被引:9,自引:1,他引:8
J. H. van den Berg E. E. Ewing R. L. Plaisted S. McMurry M. W. Bonierbale 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,93(3):307-316
Quantitative trait loci (QTLs) affecting tuberization were detected in reciprocal backcrosses between Solanum tuberosum and S. berthaultii. Linkage analyses were performed between traits and RFLP alleles segregating from both the hybrid and the recurrent parent using a set of framework markers from the potato map. Eleven distinct loci on seven chromosomes were associated with variation in tuberization. Most of the loci had small effects, but a QTL explaining 27% of the variance was found on chromosome 5. More QTLs were detected while following alleles segregating from the recurrent S. tuberosum parent used to make the backcross than were detected by following alleles segregating from the hybrid parent. More than half of the alleles favoring tuberization were at least partly dominant. Tuberization was favored by an allele from S. berthaultii at 3 of the 5 QTLs detected by segregation from the hybrid parent. The additive effects of the QTLs for tuberization explained up to 53% of the phenotypic variance, and inclusion of epistatic effects increased this figure to 60%. The most common form of epistasis was that in which presence of an allele at each of 2 loci favoring tuberization was no more effective than the presence of a favorable allele at 1 of the 2 loci. The QTLs detected for tuberization traits are discussed in relationship to those previously detected for trichome-mediated insect resistance derived from the unadapted wild species.Paper number 54 of the Department of Fruit and Vegetable Science, Cornell University 相似文献
4.
José Gabriel Segarra-Moragues Gabriela Gleiser Fernando González-Candelas 《Conservation Genetics》2008,9(4):1059-1062
An enrichment protocol was used to isolate and characterize microsatellite loci in Acer opalus, a Mediterranean tree species. Highly polymorphic microsatellite loci were required for paternity analyses in a population
of this species. Eight microsatellite loci were amplified and a total of 87 alleles were detected in a sample of 142 individuals
from one population, allowing the identification of each individual with a unique multilocus genotype. The paternity exclusion
probabilities varied from 0.261 for locus Aop820 to 0.806 for locus Aop450, and the parent-pair exclusion probabilities varied
from 0.433 for Aop820 to 0.940 for Aop450. The cumulative probabilities of exclusion for paternity and parentage of the eight
loci were both higher than 0.999, supporting the usefulness of these microsatellite loci for future paternity and parentage
analyses in A. opalus. Cross-species transferability was also assayed, supporting their potential use in other eight Acer species. 相似文献
5.
J. A. Galarza S. Roques J. Carreras-Carbonell E. Macpherson G. F. Turner C. Rico 《Conservation Genetics》2007,8(5):1251-1253
Eight polymorphic microsatellite loci were isolated and characterized for the Cardinal fish (Apogon imberbis), a coastal-reef fish endemic to the Mediterranean Sea. Characterization of 30 Cardinal fish individuals form the western
Mediterranean showed moderate to high allelic diversity ranging from 6 to 19 alleles per locus. Two loci showed significant
departures from Hardy-Weinberg equilibrium presumably due to null alleles. No evidence of linkage disequilibrium was found
for any locus pairwise comparasions. This microsatellite set could be useful for any basic population genetic studies of this
species. 相似文献
6.
An enrichment protocol was used to isolate and characterise microsatellite loci in Rosmarinus officinalis, a Mediterranean chamephyte. Twelve microsatellite loci were characterised and amplified a total of 117 alleles in a sample
of 30 individuals from one population, with an average of 9.75 alleles per locus. Observed heterozygosities ranged from 0.333
to 0.900. Cross-species transferability was also assayed in the two other species of the genus. The cumulated probabilities
of exclusion for paternity and parentage of the 12 loci were of 0.999971 and 1, respectively, supporting the usefulness of
these microsatellite loci for parentage analyses. Nine out of 12 microsatellite loci amplified in the two species and were
polymorphic detecting a total of 49 and 45 in R. eriocalyx and R. tomentosus, respectively. Twenty-two alleles were exclusive of R. eriocalyx and 12 of R. tomentosus, additionally, three alleles were shared between these two species but were otherwise absent in the analysed individuals
of R. officinalis. In total, this set of markers amplified 154 different microsatellite alleles, supporting their usefulness to conduct population
genetic, reproductive biology and hybridisation studies in Rosmarinus. 相似文献
7.
Belén G. Pardo Almudena López Paulino Martínez Carmen Bouza 《Conservation Genetics》2007,8(5):1243-1245
The long-snouted seahorse Hippocampus guttulatus is one of the two European seahorse species. We describe the isolation of the first 12 microsatellite loci in this threatened
species. These new markers were tested in non-invasive samples of 32 seahorses from NW Spain. The number of alleles ranged
from 2 to 15 (mean: 6.3) and expected heterozygosity from 0.031 to 0.912 (mean: 0.500). All loci conformed to Hardy–Weinberg
expectations and no genotypic disequilibrium was observed between any pair of loci. The theoretical exclusion probabilities
for this set of loci, when no parental information exists or when one parent is known, were 0.973 and 0.998, respectively.
This study indicates the usefulness of these novel loci for population analysis and kinship studies in Hippocampus guttulatus. Their potential application is extended to the other European seahorse species, since all loci were successfully cross-amplified
in H. hippocampus. 相似文献
8.
Abdul Muneer PM Gopalakrishnan A Musammilu KK Mohindra V Lal KK Basheer VS Lakra WS 《Molecular biology reports》2009,36(7):1779-1791
Random amplified polymorphic DNA (RAPD) and microsatellite markers were applied to evaluate the genetic variation in endemic
and endangered yellow catfish, Horabagrus
brachysoma sampled from three geographic locations of Western Ghat, South India river systems. In RAPD, of 32 10-mer RAPD primers screened
initially, 10 were chosen and used in a comparative analysis of H. brachysoma collected from Meenachil, Chalakkudy and Nethravathi River systems. Of the 124 total RAPD fragments amplified, 49 (39.51%)
were found to be shared by individuals of all 3 populations. The remaining 75 fragments were found to be polymorphic (60.48%).
In microsatellites, six polymorphic microsatellite loci were identified by using primers developed for Pangasius
hypophthalmus, Clarias
macrocephalus and Clarias
gariepinus. The identified loci were confirmed as microsatellite by sequencing after making a clone. The nucleotide sequences of 6 loci
were published in NCBI genbank. The number of alleles across the six loci ranged from 4 to 7 and heterozygosities ranged from
0.07 to 0.93. The mean number of alleles and effective number of alleles per locus were 5.00 and 3.314, respectively. The
average heterozygosity across all investigated samples was 0.72, indicating a significant deficiency of heterozygotes in this
species. RAPD and microsatellite methods reported a high degree of gene diversity and genetic distances depicted by UPGMA
dendrograms among the populations of H. brachysoma. 相似文献
9.
Electrophoretic and morphological variation was studied in 13 cultivars ofC. lanatus and 31 accessions ofC. colocynthis from Israel. Twelve enzyme systems were assayed, representing 19 loci. We found 12 commercially grown cultivars to be monomorphic at all loci. OneC. lanatus accession collected from Israel is highly polymorphic and carries alleles ofC. colocynthis; this accession is probably a representative of a locally cultivated land race grown by Bedouins for animal feed. Over a range of 500 km two forms ofC. colocynthis were identified: one which grows along the coastal plains of the Mediterranean and the other in the arid Negev and Sinal deserts. A high level of electrophoretic and morphological divergence was found between plants of the two regions, whereas within the ecotypes little variation was observed. 相似文献
10.
Microsatellite analysis reveals a progressive widening of the genetic basis in the elite durum wheat germplasm 总被引:8,自引:0,他引:8
Maccaferri M Sanguineti MC Donini P Tuberosa R 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2003,107(5):783-797
It has been argued that the level of genetic diversity in the modern durum wheat (Triticum turgidum L. var. durum) elite germplasm may have declined due to the high selection pressure applied in breeding programs. In this study, 58 accessions covering a wide spectrum of genetic diversity of the cultivated durum wheat gene pool were characterized with 70 microsatellite loci (or simple sequence repeats, SSRs). On average, SSRs detected 5.6 different allelic variants per locus, with a mean diversity index (DI) equal to 0.56, thus revealing a diversity content comparable to those previously observed with SSRs in other small-grain cereal gene pools. The mean genetic similarity value was equal to 0.44. A highly diagnostic SSR set has been identified. A high variation in allele size was detected among SSR loci, suggesting a different suitability of these loci for estimating genetic diversity. The B genome was characterized by an overall polymorphism significantly higher than that of the A genome. Genetic diversity is organised in well-distinct sub-groups identified by the corresponding foundation-genotypes. A large portion (92.7%) of the molecular variation detected within the group of 45 modern cvs was accounted for by SSR alleles tracing back to ten foundation-genotypes; among those, the most recent CIMMYT-derived founders were genetically distant from the old Mediterranean ones. On the other hand, rare alleles were abundant, suggesting that a large number of genetic introgressions contributed to the foundation of the well-diversified germplasm herein considered. The profiles of recently released varieties indicate that the level of genetic diversity present in the modern durum wheat germplasm has actually increased over time.Communicated by F. Salamini 相似文献
11.
Allozyme variation among biotypes of the brown planthopperNilaparvata lugens in the Philippines 总被引:2,自引:0,他引:2
Allozyme variation was studied in threeNilaparvata lugens biotypes infesting specific rice varieties and a biotype infesting a weed grass,Leersia hexandra. Of the 20 enzymes inN. lugens for which activity was noted, 9 were polymorphic. Eleven enzyme loci were monomorphic for the same allele in all biotype
populations; the rest were polymorphic for two or more alleles. The mean number of alleles per polymorphic locus was 2.3,
while the mean number of alleles per locus was 1.5; heterozygosity ranged from 0.02 to 0.06 (biotype 1 > biotype 3 >Leersia-infesting biotype > biotype 2). Allelic frequency differences were observed in five loci among the four biotypes. However,
the coefficient of genetic identity (I) of 0.99+ showed that the four biotype populations were genetically close relatives or merely populations ofN. lugens undergoing genetic differentiation.
This work was partly supported by a financial grant received from the Directorate for Technical Cooperation and Humanitarian
Aid, Switzerland. 相似文献
12.
Rosa Agudo Severine Roques Juan Antonio Galarza Ciro Rico Fernando Hiraldo José Antonio Donázar 《Conservation Genetics》2008,9(5):1345-1348
We developed 18 new microsatellite loci for the endangered Egyptian vulture (Neophron percnopterus). Microsatellite loci were screened for variation in two different populations belonging to separate subspecies: the nominal
N. p. percnopterus and the Canarian N. p. majorensis. Mean expected heterosygosities were respectively 0.51 and 0.46, while the mean number of alleles per locus was 4.7 and 3.9.
These new markers allow further genetic studies for the endangered Canarian Egyptian Vulture. 相似文献
13.
J. A. Galarza R. Boulay X. Cerdá C. Doums P. Federici H. Magalon T. Monnin C. Rico 《Conservation Genetics》2009,10(3):519-521
Eight polymorphic microsatellite loci were isolated and characterized for Aphaenogaster senilis, a common ant species distributed in the Western Mediterranean. Characterization of 15 individuals form southern Spain showed
moderate to high allelic diversity ranging from 2 to 9 alleles per locus. Cross-species tests on 10 individuals of A. iberica, A. gibbosa, A. subterranea and Messor maroccanus revealed successful amplification for most loci. This set of markers can be useful for population genetic studies and might
even prove useful in other phylogenetically close species of the subfamily Myrmicinae. 相似文献
14.
Nineteen natural Mediterranean fir populations, belonging to eight species and to one natural hybrid (A. ×borisii-regis), were investigated by starch and polyacrylamide gel electrophoresis. A total of 31 alleles was scored at eight loci (IDH-B, ACP-A, PER-B, 6PGD-A, 6PGD-B, MNR-B, PGI-B, PGM-A. Great variation was observed in the heterozygosity among the population studied and ranged from 0.010 (A. pinsapo) to 0.328 (A. cephalonica). The interpopulation genetic diversity was about 26% of the total genetic diversity. From the dendrogram, new phylogenetic relationships were revealed. High affinity was observed between the Calabrian fir population and the one from north-west Greece as well as betweenA. equi-trojani grown in Asia Minor and the southern Greek populations. Species specific alleles were found inA. cilicica. From the findings of the present work, a new hypothesis concerning the taxonomy, distribution and evolution ofAbies species in the Balkan Peninsula is supported. 相似文献
15.
Mikael Hedrèn 《Plant Systematics and Evolution》1997,204(1-2):21-37
Schoenus ferrugineus andS. nigricans have restricted distributions in Sweden and are almost exclusively confined to calcareous fen habitats. AtS. nigricans sites,S. ferrugineus is usually also present, and hybrids are frequently found. In this report, I used allozymes to estimate the amount of gene flow between the two species, and to compare the partitioning of genetic diversity in each of them. Thirteen loci were analysed at eight different enzyme systems. Seven loci were variable between or within the species. The two species had completely different alleles at two of the seven variable loci, whereas there was overlap at five loci. In all, 22 different alleles were found. Six of these alleles were confined toS. nigricans, and five alleles were confined toS. ferrugineus. Nei's genetic identity was 0.55.—InS. ferrugineus, three loci (23%) were polymorphic, and the average number of alleles per polymorphic locus was 2.0 (each polymorphic locus had two alleles). InS. nigricans, three loci (23%) were polymorphic, and the average number of alleles per polymorphic locus was 2.3.—The proportion of genetic diversity due to variation among sites (G
ST) was fairly similar in the two species, mean over loci = 0.12 inS. ferrugineus and 0.15 inS. nigricans. However, the proportion of genetic diversity due to variation among individuals within sites (G
IS) differed markedly between the two species, mean over loci = 0.54 inS. ferrugineus and 0.17 inS. nigricans. Accordingly, there was a much higher individual heterozygosity inS. nigricans than inS. ferrugineus. — Most hybrids were interpreted as F1 hybrids. However, a small proportion, 0.5–1.6 %, were Fn hybrids or back-crosses.—On the Swedish mainland, all former occurrences ofS. nigricans are extinct, but viable hybrids are still present at a few sites in southernmost Sweden. 相似文献
16.
Genetic diversity and differentiation within and among nine G. morsitans morsitans populations from East and southern Africa was assessed by examining variation at seven microsatellite loci and a mitochondrial
locus, cytochrome oxidase (COI). Mean COI diversity within populations was 0.63 ± 0.33 and 0.81 taken over all populations. Diversities averaged over microsatellite
loci were high (mean number of alleles/locus ≥7.4; mean H
E ≥ 65%) in all populations. Diversities averaged across populations were greater in East Africa (mean number of alleles = 22 ± 2.6;
mean h
e = 0.773 ± 0.033) than in southern Africa (mean number of alleles = 18.7 ± 4.0; mean h
e = 0.713 ± 0.072). Differentiation among all populations was highly significant (R
ST = 0.25, F
ST = 0.132). Nei’s G
ij
statistics were 0.09 and 0.19 within regions for microsatellites and mitochondria, respectively; between regions, G
ij
was 0.14 for microsatellites and 0.23 for mitochondria. G
ST among populations was 0.23 for microsatellite loci and 0.40 for mitochondria. The F, G and R statistics indicate highly restricted gene flow among G. m. morsitans populations separated over geographic scales of 12–917 km. 相似文献
17.
Twenty enzyme loci were examined in the diploid species ofTriticum andAegilops for allelic variation by starch gel electrophoresis. SectionSitopsis, including the five species,Ae. speltoides, Ae. lingissima, Ae. sharonensis, Ae. bicornis andAe. searsii form a close subgroup withAe. speltoides slightly removed from the others.T. monococcum s. lat., was found to be closest to the species of theSitopsis group.Ae. comosa, Ae. umbellulata andAe. uniaristata form a second subgroup withAe. caudata most closely related to these species.Ae. squarrosa appears almost equally related to all of the species, showing no special affinity for any one species group. Nineteen out of twenty loci examined were polymorphic with a mean of 6.7 alleles per locus. Species could be, for most loci, characterized by the presence of predominant alleles. A conspicious genetic characteristic ofTriticum-Aegilops is the sharing of these predominant alleles between species. Within species variation is characterized by a diffuse distribution of secondary alleles. 相似文献
18.
Chin-Sung Chang Do Yol Choi Hui Kim Tae Yoon Park Yong-Sik Kim 《Journal of Plant Biology》2005,48(4):339-350
Patterns of variation at 27 allozyme loci were investigated in the endangered endemic plantMegaleranthis saniculifolia. Levels of allozyme variation (A = 1.47,P = 40%,He = 0.088) were also compared with other endemic plant species. Genetic divergence between populations was very high (G
st
= 0.271 ), with moderate to high interpopulation differentiation, which probably arose through historical bottlenecks in
a landscape of habitat fragmentation and/or human influence. The percentage of polymorphic loci, heterozygosity, and mean
number of alleles per locus were positively related to population size, probably due to the stochastic loss of rare alleles
in the smaller populations. Individuals in the small and marginal populations (TB, KD, and CJ) showed higher proportions of
fixed loci. These ecologically marginal populations were typically more distant from the nearest neighboring population and
were more genetically distinct from one another. The genetic structure of the current population ofM. saniculifolia is probably the result of local extinctions of intervening populations. This, in turn, is due to the Pleistocene climatic
change and increased habitat destruction. A positive association appears to exist between genetic diversity and population
size. Although these small population sizes are more sensitive to stochastic events, securing a certain number of individuals
from the three larger populations (SB, JB, and TG) could be accomplished as part of a conservation strategy. In addition,
it is important to prioritize populations in different regions in order to limit population declines caused by large-scale
environmental catastrophes. 相似文献
19.
Comparative analysis of microsatellite DNA polymorphism in landraces and cultivars of rice 总被引:27,自引:0,他引:27
G. P. Yang M. A. Saghai Maroof C. G. Xu Qifa Zhang R. M. Biyashev 《Molecular & general genetics : MGG》1994,245(2):187-194
Genetic polymorphisms of ten microsatellite DNA loci were examined among 238 accessions of landraces and cultivars that represent a significant portion of the distribution range for both indica and japonica groups of cultivated rice. In all, 93 alleles were identified with these ten markers. The number of alleles varied from a low of 3 or 4 at each of four loci, to an intermediate value of 9–14 at five loci, and to an extra-ordinarily high 25 at one locus. The numbers of alleles per locus are much larger than those detected using other types of markers. The number of alleles detected at a locus is significantly correlated with the number of simple sequence repeats in the targeted microsatellite DNA. Indica rice has about 14% more alleles than japonica rice, and such allele number differences are more pronounced in landraces than in cultivars. The indica-japonica differentiation component accounted for about 10% of the diversity in the total sample, and twice as much differentiation was detected in cultivars as in landraces. About two-thirds as many alleles were observed in cultivars as in landraces; another two-thirds of the alleles in the cultivar group were found in modern elite cultivars or parents of hybrid rice. The majority of the simple sequence repeat (SSR) alleles that were present in high or intermediate frequencies in landraces ultimately survived into modern elite cultivars and hybrids. The greater resolving power and the efficient production of massive amounts of SSR data may be particularly useful for germplasm assessment and evolutionary studies of crop plants. 相似文献
20.
Ashley MV Wilk JA Styan SM Craft KJ Jones KL Feldheim KA Lewers KS Ashman TL 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2003,107(7):1201-1207
The objectives of the present study were to develop microsatellite markers for the wild strawberry, Fragaria virginiana, to evaluate segregation patterns of microsatellite alleles in this octoploid species, and assess genetic variability at microsatellite loci in a wild population. A genomic library was screened for microsatellite repeats and several PCR primers were designed and tested. We also tested the use of heterologous primers and found that F. virginiana primers amplified products in cultivated strawberry, Fragaria × ananassa Duch. and Fragaria chiloensis. Similarly, microsatellite loci developed from cultivated strawberry also successfully amplified F. virginiana loci. We investigated four microsatellite loci in detail, three developed from F. virginiana and one from cultivated strawberry. A survey of 100 individuals from a population of F. virginiana in Pennsylvania demonstrated high heterozygosities (He or gene diversity ranged from 0.80 to 0.88 per locus) and allelic diversity (12–17 alleles per locus), but individual plants had no more than two alleles per locus. Segregation patterns in parents and progeny of two controlled crosses at these four loci were consistent with disomic Mendelian inheritance. Together these findings suggest that the genome of F. virginiana is "highly diploidized" and at least a subset of microsatellite loci can be treated as codominant, diploid markers. Significant heterozygote deficiencies were found at three of the four loci for hermaphroditic individuals but for only one locus among females in this gynodioecious species.Communicated by J. Dvorak 相似文献