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1.
The deadly poisonous Amanita phalloides is common along the west coast of North America. Death cap mushrooms are especially abundant in habitats around the San Francisco Bay, California, but the species grows as far south as Los Angeles County and north to Vancouver Island, Canada. At different times, various authors have considered the species as either native or introduced, and the question of whether A. phalloides is an invasive species remains unanswered. We developed four novel loci and used these in combination with the EF1α and IGS loci to explore the phylogeography of the species. The data provide strong evidence for a European origin of North American populations. Genetic diversity is generally greater in European vs. North American populations, suggestive of a genetic bottleneck; polymorphic sites of at least two loci are only polymorphic within Europe although the number of individuals sampled from Europe was half the number sampled from North America. Endemic alleles are not a feature of North American populations, although alleles unique to different parts of Europe were common and were discovered in Scandinavian, mainland French, and Corsican individuals. Many of these endemic European haplotypes were found together at single sites in California. Early collections of A. phalloides dated prior to 1963 and annotated using sequences of the ITS locus proved to be different species of Amanita. The first Californian collections that we confirmed as A. phalloides were made from the Del Monte Hotel (now the Naval Postgraduate School) in Monterey, and on the campus of the University of California, Berkeley, in 1938 and in 1945. These historical data are used in combination with data on A. phalloides’ current distribution to estimate a rate of spread for A. phalloides in California. Many species of ectomycorrhizal (EM) fungi have been introduced across and among continents, but with this evidence, the death cap becomes the only known invasive EM fungus in North America.  相似文献   

2.
Single nucleotide polymorphisms or SNPs are the most abundant form of genetic variation in the genome of plants and animals. Microsatellites are hypervariable regions of genome, while their flanking regions are assumed to be as conserved as the average of the genome. In the present study, flanking sequences of 10 microsatellite loci were compared in different cultivars of Vitis to determine the existing polymorphism. For every microsatellite, about 8 homozygous cultivars (regarding the microsatellite genotype) were chosen for sequencing. A total of 45 different varieties of Vitis and 91 sequences were analysed. Sequence polymorphisms were detected for all the microsatellite flanking regions studied, including single nucleotide polymorphisms (SNPs), insertions and deletions. The number of identified changes varied considerably among the loci with a frequency of one polymorphism every 41 nucleotides, being VVMD5 the most polymorphic one. A number of SNPs were used to design SNP markers, which were scored by dideoxy single base primer extension and capillary electrophoresis methodology. These SNP markers were employed to genotype 21 cultivars of Vitis vinifera and 4 varieties of other Vitis species. The utility of the markers developed as well as their utility for varietal identification and pedigree studies is discussed, using a similar study carried out with the 10 microsatellites as a reference.  相似文献   

3.
  1. Understanding plant‐insect interactions is an active area of research in both ecology and evolution. Much attention has been focused on the impact of secondary metabolites in the host plant or fungi on these interactions. Plants and fungi contain a variety of biologically active compounds, and the secondary metabolite profile can vary significantly between individual samples. However, many experiments characterize the biological effects of only a single secondary metabolite or a subset of these compounds.
  2. Here, we develop an exhaustive extraction protocol using an accelerated solvent extraction protocol to recover the complete suite of cyclopeptides and other secondary metabolites found in Amanita phalloides (death cap mushrooms) and compare its efficacy to the “Classic” extraction method used in earlier works.
  3. We demonstrate that our extraction protocol recovers the full suite of cyclopeptides and other secondary metabolites in A. phalloides unlike the “Classic” method that favors polar cyclopeptides.
  4. Based on these findings, we provide recommendations for how to optimize protocols to ensure exhaustive extracts and also the best practices when using natural extracts in ecological experiments.
  相似文献   

4.
Four microsatellite‐enriched DNA libraries yielded 35 microsatellite loci from 100 primer pairs designed for Pacific lion‐paw scallop, Nodipecten subnodosus. The number of alleles ranged from four to 28. Three of the 35 loci were not in Hardy–Weinberg equilibrium and linkage disequilibrium was found for one pair of loci. These microsatellites will be used to analyse the population structure of the species in Mexico's Baja Peninsula to propose management strategies for scallop aquaculture development. Twenty‐six primer pairs cross‐amplified in Nodipecten nodosus, whereas none (Argopecten ventricosus) or few cross‐amplified in the Argopecten species.  相似文献   

5.
Polymorphic microsatellite loci were identified in order to determine paternity in a captive population of the zebra finch, Taeniopygia guttata. Primer sets from 93 published passerine microsatellite sequences were tested for cross‐species amplification. Thirteen loci were found to be polymorphic, of which, eight displayed null alleles and one locus (Ase50) was found to be Z‐chromosome linked.  相似文献   

6.
We developed microsatellite loci for the southern pine beetle (Dendroctonus frontalis). Twelve microsatellite loci were identified. Eight loci were polymorphic and sufficiently variable in 62 individuals (expected heterozygosity ranged from 0.707 to 0.880) to investigate population structure. All loci conformed to HWE except Dfr‐14, which showed heterozygote excess, and no two loci deviated from linkage equilibrium. The loci were tested for cross‐species amplification in four species of Dendroctonus (D. valens, D. terebrans, D. brevicomis, and D. ponderosae). Seven loci were polymorphic in at least one of the species tested.  相似文献   

7.
Twelve microsatellite markers were isolated from Lolium multiflorum. Allelic variability and cross‐species amplification were assessed on 16 individuals of each of the three grassland species L. multiflorum, Lolium perenne and Festuca pratensis. Cross‐species amplification success was 100% for L. perenne and 83% for F. pratensis. The number of alleles detected ranged from one to 14 with an average of 3.4. While three microsatellite loci were polymorphic in all three species, one marker produced species‐specific alleles in all three species. These microsatellite markers provide a valuable tool for population genetic studies within and among species of the Festuca–Lolium complex.  相似文献   

8.
Twenty‐one new polymorphic microsatellite markers were isolated in the phytopathogenic fungus Venturia inaequalis, the causal agent of apple scab. An enrichment protocol was used to isolate microsatellite loci and the level of polymorphism was assessed on 44 European isolates. All loci were polymorphic with an average of 9.1 alleles per locus (range 2–24). Tests of cross‐species amplifications suggest that at least some of these microsatellites could be used in different species, mainly Spilocaea pyracanthae and S. eriobotryae.  相似文献   

9.
10.
The identification of microsatellite loci in Rubus hochstetterorum provides an important tool for the characterization and conservation of wild populations of this species. Cross‐species amplification of markers may be of particular interest for the study of other Rubus species. In this study, 41 simple sequence repeat markers were identified in a genomic library of R. hochstetterorum. Fifteen of the identified microsatellite loci were characterized in a set of 30 samples and revealed to be polymorphic with three to 19 alleles per locus. All the identified markers allowed cross‐species amplification in at least one of the other three tested species from the Rosaceae family.  相似文献   

11.
Microsatellite loci were isolated in Crassostrea corteziensis using (GT)n, (CT)n and (CTGT)n‐enriched genomic libraries. Within each of 45 sequenced clones, an average of three microsatellite regions (156 total) were observed. Thirty‐three primers were designed, from which 11 microsatellite loci amplified. Ten of those were polymorphic, with a range of two to 30 alleles. Three loci were not in Hardy–Weinberg equilibrium, and linkage disequilibrium was found for six pairs of loci. These microsatellite loci will be further tested for segregation distortions and null alleles to establish a set for population genetic studies of the species in the Northwest coasts of Mexico, and for optimization of aquaculture development. Seven of the microsatellite loci cross‐amplified in Crassostrea palmula, a sympatric species, and will be useful in further genetic studies.  相似文献   

12.
A genomic library from the commercial diploid cultivar ‘Ouro’ (Musa acuminata), enriched for CT‐ and GT‐repeats, was used to isolate and characterize 23 microsatellite loci. These loci were tested in 10 Musa genotypes, representing various Musa genomic groups with distinct ploidy level. The number of alleles per locus ranged from one to seven, and 20 loci were highly informative. Four loci appeared to amplify B genome‐specific alleles, while three loci seemed to be absent in the B genome. The polymorphism revealed by these loci will be extremely useful for genetic mapping, marker‐assisted selection, germplasm characterization and evolutionary studies in Musa.  相似文献   

13.
The decline of the Barrens topminnow (Fundulus julisia), a small schooling fish endemic to the Barrens Plateau region of Middle Tennessee, is one of the most dramatic cases of species imperilment in eastern North America. Loss of undisturbed habitat, coupled with the introduction of the invasive Western Mosquitofish (Gambusia affinis) has led to the extirpation of 12 out of 14 natural populations since the 1980s. Identified is a set of 14 microsatellite loci to improve conservation and management strategies for the species. Four loci were cross‐amplified using primers designed for congeneric taxa and 10 loci were developed from whole genome Illumina sequencing. Initial surveys in two populations suggest significant structuring of genetic variation and differing levels of heterozygosity among populations. These markers will contribute valuable information to ongoing conservation and management efforts.  相似文献   

14.
Eight polymorphic di‐ and trinucleotide microsatellite loci suitable for population genetic analysis were developed in Locusta migratoria from a partial phagemid genomic library enriched for microsatellite inserts. The expected heterozygosity at these loci ranges from 0.45 to 0.97, with the observed allele numbers varying between nine and 45. The overall microsatellite cloning efficiency in L. migratoria is 14%, suggesting that in migratory locusts, microsatellite sequences are abundant and should provide a valuable and easily accessible source of nuclear markers for genetic studies. These microsatellite loci were highly Locusta‐specific, with only very limited cross‐species applicability.  相似文献   

15.
We isolated and characterized six polymorphic microsatellite loci for the polychaete tubeworm, Hydroides elegans. Two additional loci were not reliably scorable and estimates of heterozygosity were obtained for the other six. In addition, cross‐species amplification was successful for two loci using the congener H. hexagonus. Given that few microsatellite loci are available for polychaetes, these markers will be useful in assessing dispersal and gene flow in H. elegans and probably also other polychaetes.  相似文献   

16.
Here we present a new set of 22 microsatellite loci isolated from Chlamydotis undulata undulata, an endangered Houbara bustard found across North Africa. The number of alleles per locus ranged from one to nine, and heterozygosities ranged from 0.167 to 0.944. Total exclusionary probabilities using these loci for the first and the second parent were 0.992932 and 0.999915, respectively. Successful cross‐amplification was observed in eight other Otididae species (12–22 of the 22 loci). These microsatellite markers are powerful tools for genetic identification, paternity assignment and population genetic studies.  相似文献   

17.
We describe the first microsatellite loci for the gynogenetic Amazon molly, Poecilia formosa, an all‐female species arisen through hybridization of the bisexual species Poecilia mexicana and Poecilia latipinna. The loci showed one to six alleles and an expected heterozygosity between zero and 0.75. As expected with parthenogenetic inheritance, most loci were either constantly homozygous (five loci) or constantly heterozygous (eight loci). For six loci, both heterozygotes and homozygotes occurred. This and the fact that some loci only showed alleles of one of the ancestral species could indicate genome homogenization through mitotic gene conversion. Our new loci conformed to the hybrid origin of Amazon molly and are also applicable to both ancestral bisexual species.  相似文献   

18.
We describe eight new microsatellite loci for the critically endangered fire‐bellied toad, Bombina bombina. Seven of them are polymorphic with two to seven alleles per locus, an expected heterozygosity between 0.41 and 0.8, and an observed heterozygosity between 0.27 and 0.7. The yield of new loci was relatively low, presumably due to mildly repetitive sequence motifs in microsatellite flanking regions. As typical for anurans, cross‐species amplification was limited (here, to congeners Bombina orientalis and Bombina variegata). Combining these new loci with those already available provides a reasonable number of loci for population studies and pedigree analysis in Bombina.  相似文献   

19.
A significant challenge to population genetic studies of the dengue vector, Aedes aegypti, has been the lack of polymorphic microsatellite loci. In an effort to develop useful markers, we evaluated the genetic variation at 17 microsatellite loci identified in the A. aegypti genome. Nine loci with at least five alleles were identified in field‐collected specimens from Thailand. An additional two loci carried five alleles if samples from an A. aegypti laboratory colony were included. Our results greatly increase the number of highly variable markers available for the study of the genetics and the population structure of this medically important species.  相似文献   

20.
We developed eight polymorphic microsatellite loci for Collinsia verna (Veronicaceae). In a sample of 18–35 individuals from a single population, we found two to 15 alleles per locus (mean 8.3). We also tested these loci for cross‐amplification in all 22 species in the tribe Collinseae. Overall, more than half the species in the tribe amplified one microsatellite while three species most closely related to C. verna (Collinsia violacea, Collinsia parviflora and Collinsia grandiflora) amplified multiple microsatellite loci. These microsatellite loci will be used in future studies of mating system in this tribe and other quantitative genetic and population genetic studies.  相似文献   

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