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1.
We developed 11 polymorphic microsatellite DNA markers for an Australian native shrub Banksia attenuata. The number of alleles per locus in 50 individuals varied from five to 18, observed and expected heterozygosities ranged from 0.300 to 0.740 and from 0.537 to 0.918, respectively. Six loci showed no significant deviation from Hardy–Weinberg equilibrium (P > 0.05), and null alleles appear to exist at locus BA‐B1. All loci showed independent inheritance.  相似文献   

2.
We developed 11 polymorphic microsatellite DNA markers for an Australian native plant, Daviesia triflora. The number of alleles per locus in 40 individuals varied from four to 19, and observed and expected heterozygosities ranged from 0.450 to 0.925 and from 0.497 to 0.899, respectively. Nine loci showed no significant deviation from Hardy–Weinberg equilibrium (P > 0.05), and null alleles appear to exist at loci DT‐A102 and DT‐B103. All loci showed independent inheritance.  相似文献   

3.
The pattern of accumulation of genetic variation over time in seed banks is poorly understood. We examined the genetic structure of the aerial seed bank of Banksia hookeriana within a single 15-year-old population in fire-prone southwestern Australia, and compared genetic variation between adults and each year of a 9-year-old seed bank using amplified fragment length polymorphism (AFLP). B. hookeriana is well suited to the study of seed bank dynamics due to the canopy storage of its seeds, and because each annual crop can be identified. A total of 304 seeds from nine crop years and five maternal plants were genotyped, along with 113 plants from the adult population. Genetic variation, as assessed by the proportion of polymorphic markers (P(p)) and Shannon's index (I), increased slightly within the seed bank over time, while gene diversity (H(j)), did not change. P(p), I, and H(j) all indicated that genetic variation within the seed bank quickly approached the maximal level detected. Analysis of molecular variance revealed that less than 4% of variation could be accounted for by variation among seeds produced in different years, whereas there was greater differentiation among maternal plants (12.7%), and among individual seeds produced by different maternal plants (83.4%). With increasing population age, offspring generated each year were slightly more outbred, as indicated by an increase in the mean number of nonmaternal markers per offspring. There were no significant differences for H(j) or I between adults and the seed bank. Viability of seeds decreased with age, such that the viability of 9-year-old seeds was half that of 2-year-old seeds. These results suggest that variable fire frequencies have only limited potential to influence the amount of genetic variation stored within the seed bank of B. hookeriana.  相似文献   

4.
To assess whether wide outcrossing (over 30 km) in the naturally fragmented Banksia ilicifolia R.Br. increases the ecological amplitude of offspring, we performed a comparative greenhouse growth study involving seedlings of three hand-pollinated progeny classes (self, local outcross, wide outcross) and a range of substrates and stress conditions. Outcrossed seedlings outperformed selfed seedlings, with the magnitude of inbreeding depression as high as 62% for seed germination and 37% for leaf area. Wide outcrossed seedlings outperformed local outcrossed seedlings, especially in non-native soils, facilitated in part by an improved capacity to overcome soil constraints through greater root carboxylate exudation. Soil type significantly affected seedling growth, and waterlogging and water deficit decreased growth, production of cluster roots, root exudation and total plant P uptake. Our results suggest that the interaction of narrow ecological amplitude and the genetic consequences of small fragmented populations may in part explain the narrow range of local endemics, but that wide outcrossing may provide opportunities for increased genetic variation, increased ecological amplitude and range expansion.  相似文献   

5.
A genomic library was constructed and 10 novel polymorphic microsatellite markers were developed for Banksia nivea subsp. uliginosa, a woody shrub endemic to the southwest of Western Australia. Polymorphism was investigated for these markers in 30 individuals from one population located in restricted habitat at the base of the Whicher Range east of Busselton. Expected heterozygosity ranged from 0.124 to 0.898 and averaged 0.570. Observed heterozygosity ranged from 0.133 to 0.933 and averaged 0.544. The number of alleles per locus ranged from 2.0 to 16.0 and averaged 7.3. These markers also produced amplification products in three other Banksia species and will be used to assay genetic diversity in these species.  相似文献   

6.
Abstract Long-term canopy storage of seeds in fruits (bradyspory) varies among species and is thought to be related to the fire regime experienced by the plant community. This study sought to quantify intraspecific variation in bradyspory among nine populations of Banksia serrata (Proteaceae) on the south coast of New South Wales. Marked differences were found between populations, ranging from more than 30% of follicles open at two coastal sites, to less than 5% of follicles open at two inland heath sites. Low levels of bradyspory occurred particularly in coastal sites which also had Banksia integrifolia, a non-bradysporous species, present. In addition to spontaneous follicle opening without fire, fall of infructes-cences to the ground after breaking of branches was observed to be a major contributor to seed release. At three sites where fire had not occurred for many years, the amount of seedling establishment since the last fire corresponded well with levels of bradyspory; there were no inter-fire recruits at the site with the strongest bradyspory, while at the site with the weakest bradyspory there were numerous inter-fire plants, some with lignotubers large enough to be able to tolerate the next fire. It is argued that populations of B. serrata exhibit variable patterns of recruitment, depending on the site characteristics, ranging from complete dependence on fire for population maintenance to bet-hedging (spreading potential recruitment between fire events and inter-fire periods). Variations in populations and reproductive characteristics among sites make the application of demographic models to management decisions habitat-specific.  相似文献   

7.
Microsatellite markers were developed for the Australian bird-pollinated woody shrub Banksia sphaerocarpa var. caesia to study gene flow among populations in a highly fragmented landscape. Eight loci were developed, and in a sample of 40 individuals from one population, the number of alleles per locus ranged from five to 21 and observed heterozygosities ranged from 0.385 to 0.914. All eight loci showed independent inheritance. Analysis of open-pollinated progeny arrays confirmed Mendelian inheritance at seven loci, while null alleles were suspected at the remaining locus.  相似文献   

8.
9.
Eight polymorphic microsatellite loci were isolated from the partial genomic library of the rhinoceros auklet Cerorhinca monocerata. The heterozygosities observed at the isolated loci using eight primer sets in 46 nestlings from one breeding colony in Japan ranged from 0.311 to 0.773, and all but one locus did not deviate from the Hardy–Weinberg expectations. Cross‐species amplification in the tufted puffin Fratercula cirrhata was successfully performed using six of the eight primer sets, indicating their applicability to this species.  相似文献   

10.
The isolation and characterization of the first polymorphic microsatellite markers for the mangrove crab Ucides cordatus are described. The number of alleles at each locus ranged from three to 25, mean of nine alleles, in 46 crabs captured in two Brazilian mangroves. The markers averaged high levels of observed (0.709 ± 0.183) and expected (0.716 ± 0.170) heterozygosities. Departures from Hardy-Weinberg equilibrium were observed at two loci. Linkage disequilibrium tests were not significant and no evidence of null alleles was detected. All these microsatellite loci are expected to be useful in estimating fine-scale population processes of this valuable mangrove species currently subjected to excessive fishing efforts.  相似文献   

11.
Ten GATA microsatellite DNA markers were isolated and characterized from black grouse (Tetrao tetrix) using an enrichment cloning procedure. High levels of heterozygosity (mean HO = 0.74 ± 0.026), and a large number of alleles (range = 5–16) were resolved in 70 individuals, indicating these markers will be useful for examining parentage, inbreeding and population structure in black grouse. No evidence for linkage disequilibrium or the presence of null alleles was found.  相似文献   

12.
Seven polymorphic microsatellite loci are described in the marine intertidal gastropod Littorina saxatilis. Preliminary data on allelic variation of these loci in a White Sea population of L. saxatilis are presented in order to assess their potential utility as high‐resolution genetic markers for this model species.  相似文献   

13.
Florida manatees (Trichechus manatus latirostris) are marine mammals that inhabit the coastal waters and rivers of the southeastern USA, primarily Florida. Previous studies have shown that Florida manatees have low mitochondrial DNA variability, suggesting that nuclear DNA loci are necessary for discriminatory analyses. Here we report 10 polymorphic microsatellite loci with an average of 4.2 alleles per locus, and average heterozygosity of 50.1%. These loci have been developed for use in population studies, parentage assignment, and individual identification.  相似文献   

14.
A genomic library was constructed and 13 polymorphic microsatellite markers were developed for Hakea oldfieldii, a woody shrub endemic to southwest Western Australia. Polymorphism was investigated for these markers in 28 individuals from a single population located in restricted habitat at the base of the Whicher Range south of Busselton. Expected heterozygosity ranged from 0.279 to 0.770 and averaged 0.633. Observed heterozygosity ranged from 0.321 to 0.786 and averaged 0.598. The number of alleles per locus ranged from 2.0 to 6.0 and averaged 4.5. These markers will be used to assay genetic diversity and pollen dispersal in this species.  相似文献   

15.
Six polymorphic microsatellite loci were isolated and characterized from the temporary social parasitic ant Lasius fuliginosus by a highly efficient enrichment procedure. Observed allele numbers ranged from three to 20 per locus, whereby four out of the six tested loci had more than 10 alleles and showed both observed and expected heterozygosities greater than 70%. For each locus we present suitable primer sequences. With these microsatellite markers we will be able to reveal colony and population structure of L. fuliginosus.  相似文献   

16.
Squid populations are being put under rapidly increasing commercial fishing pressure worldwide. The same species are known to be susceptible to extreme population fluctuations, so detailed knowledge of population substructuring and genetic diversity is essential for rational management. We present a set of microsatellite DNA loci suitable for population genetic analysis of Loligo gahi, the squid species subject to the most detailed monitoring and fishery control (around the Falkland Islands), with the future aim of generating management‐related information to aid conservation of this valuable natural resource.  相似文献   

17.
To investigate the population genetic structure of the goosander (Mergus merganser) in Europe and to identify populations with a significant conservation value, we isolated nine microsatellite loci, and screened them in the subspecies Mergus merganser merganser and Mergus merganser americanus. All markers were polymorphic with two to 15 alleles per locus. Average observed and expected heterozygosity values were 0.422 and 0.624, respectively, for the European and 0.497 and 0.667, respectively, for the North American subspecies. Only one marker departed significantly from Hardy–Weinberg expectations in both subspecies. This marker was highly variable but homozygous in all females, suggesting a sex‐linked inheritance.  相似文献   

18.
Bactrocera cacuminata (Hering) is a nonpest member of the Bactrocera dorsalis complex offering a platform to check hypotheses extrapolated from the more studied pest species. Six polymorphic microsatellite loci were isolated from enriched genomic libraries constructed using a biotin/streptavidin capture protocol. Allele number varied between three and nine; the expected heterozygosity ranged between 0.29 and 0.81. No significant deviations from Hardy–Weinberg equilibrium or linkage disequilibrium were found. These microsatellite markers have potential to be used to examine population structure and mating systems in this tropical fruit fly.  相似文献   

19.
20.
We have isolated and characterized twelve novel polymorphic microsatellite loci from Scapharca subcrenata to analyse the population structure. The number of observed alleles per locus ranged from 3 to 17. Observed heterozygosity (H O) ranged from 0.321 to 0.929. Cross-species amplification was tested successfully in three other bivalve species. These microsatellite markers will be useful for genetic diversity studies of S. subcrenata and other Lamellibranchia species.  相似文献   

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