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1.
We describe eight new polymorphic microsatellite loci (5 dinucleotide and three trinucleotide) for the eastern phoebe (Sayornis phoebe) to complement five previously published loci. The number of alleles per locus ranged from 3 to 15 and observed heterozygosities ranged from 0.33 to 0.91. Preliminary screening revealed that loci were polymorphic in other Tyrannidae: Empidonax virescens (n = 10), Tyrannus tyrannus (n = 10), Tyrannus vociferans (n = 5), and Tyrannus melancholicus (n = 28).  相似文献   

2.
In the study area (Yanjiaping Village, Hebei Province, China), grazing extensity varies at different locations, small and discontinuous croplands are imbedded in some arid grassland, which are habitats for the melitaeine butterflies, Euphydryas aurinia and Melitaea phoebe. These two species of butterfilies coexist in this area, in which grazing and cultivation are the main disturbances. Grazing and cultivation have a reciprocal effect on E. aurinia, rather than M. phoebe. We observed that E. aurinia preferred to occupy patches with moderate grazing and imbedded with small and discontinuous croplands, where E. aurinia also has high population density. The percentage of E. aurinia larval groups in the ribbings was significantly higher than that of M. phoebe, whereas larvae of both species tended to increase in recent years. Our data also showed that the population density and the patch occupancy rate of both E. aurinia and M. phoebe were the highest under moderate grazing. It indicates that cultivation of small and discontinuous croplands within the patch has a significant effect on the population density of both species of melitaeine butterflies. Thus, to artificially create or maintain semi-natural habitats, complemented by moderate grazing, might be an ecological strategy to conserve melitaeine butterflies effectively. Considering the distinct impacts of cultivation and grazing on the population distribution and dynamics of the two different species, human disturbance in the mountainous area might be strategically involved in proposing conservation plans for the target species in the future.  相似文献   

3.
ABSTRACT Eastern Phoebes (Sayornis phoebe) persistently pump their tails when perched, and the function of this behavior is unclear. We tested four hypotheses concerning the possible functions of tail pumping, including the (1) balance hypothesis, (2) signal‐aggression‐to‐conspecifics hypothesis, (3) foraging‐enhancement hypothesis, and (4) predator‐deterrent hypothesis. Eastern Phoebes were monitored from 1 April to 1 August 2006 and 1 June to 1 August 2007 in Madison County, Kentucky. Phoebes were captured in mist nets and marked with unique combinations of colored‐leg bands. Each focal phoebe was observed one to two times a week and tail‐pumping rates, wind velocity, and perch characteristics were recorded. Our results provided support only for the predator‐deterrent hypothesis. Phoebes exhibited a significant increase in tail‐pumping rates in the presence of a potential predator (Eastern Screech‐Owl, Megascops asio), suggesting that tail pumping, along with increased rates of calling, informs potential predators that a phoebe is aware of their presence and, therefore, more difficult to capture. Phoebes, however, tail pump regardless of whether a predator has been sighted and such movement could make phoebes easier to detect. If so, and if a detected phoebe provides no additional cues (calling) to indicate awareness of a predator, an attack might actually be more likely. However, tail pumping may be beneficial, regardless of whether a predator has been detected, if it serves as a continuous, honest predator‐deterrent signal. This would be the case if predators learned to associate tail pumping and phoebes, and also learned that phoebes, with their alert posture, small size, and impressive aerial maneuvering abilities, represent low reward, difficult‐to‐capture prey. If so, then both phoebes and predators would benefit, with phoebes less likely to be attacked and predators not initiating attacks that would waste time and energy and alert other potential prey to their presence.  相似文献   

4.
The Fucaceae is a family of brown seaweeds that dominate and frequently co‐occur on North Atlantic rocky shores. We developed nine polymorphic microsatellite markers for the fucoid seaweeds Fucus vesiculosus, F. serratus and Ascophyllum nodosum using a combined, enriched library. Six of these loci were polymorphic in at least two species, showing from two to eight alleles with heterozygosities ranging from 0.41 to 0.85. Loci were also tested on F. spiralis, revealing five polymorphic microsatellite loci in this species.  相似文献   

5.
Three different DNA mapping techniques—RFLP, RAPD and AFLP—were used on identical soybean germplasm to compare their ability to identify markers in the development of a genetic linkage map. Polymorphisms present in fourteen different soybean cultivars were demonstrated using all three techniques. AFLP, a novel PCR-based technique, was able to identify multiple polymorphic bands in a denaturing gel using 60 of 64 primer pairs tested. AFLP relies on primers designed in part on sequences for endonuclease restriction sites and on three selective nucleotides. The 60 diagnostic primer pairs tested for AFLP analysis each distinguished on average six polymorphic bands. Using specific primers designed for soybean fromEco RI andMse I restriction site sequences and three selective nucleotides, as many as 12 polymorphic bands per primer could be obtained with AFLP techniques. Only 35% of the RAPD reactions identified a polymorphic band using the same soybean cultivars, and in those positive reactions, typically only one or two polymorphic bands per gel were found. Identification of polymorphic bands using RFLP techniques was the most cumbersome, because Southern blotting and probe hybridization were required. Over 50% of the soybean RFLP probes examined failed to distinguish even a single polymorphic band, and the RFLP probes that did distinguish polymorphic bands seldom identified more than one polymorphic band. We conclude that, among the three techniques tested, AFLP is the most useful.  相似文献   

6.
B. John  M. King 《Genetica》1985,66(3):183-194
The distribution of chiasmata and their relationship to the presence of fixed and polymorphic heterochromatic segments is described in seven grasshopper species. In six of these, Cryptobothrus chrysophorus, Trimerotropis bilobata, Calliptamus wattenwylianus, Arcyptera fusca, Pezotettix giorni and Acrotylus insubricus, the presence of terminally located polymorphic heterochromatic segments leads to a radical redistribution of chiasmata away from the segments to more proximal sites. Polymorphisms for proximal heterochromatic segments exist in the first three of these species and they lead to a predominance of terminally associated homologues at male meiosis. In Oxya japonica where both polymorphic and fixed blocks are present, the polymorphic blocks have a similar pronounced effect on chiasma distribution, whereas the fixed blocks have no such effect.  相似文献   

7.
Ten polymorphic microsatellite repeat markers were identified from Crassostrea gigas, expressed sequence tags (EST) deposited in public sequence database. Number of alleles per locus ranged from three to 18, expected and observed heterozygosities ranged from 0.071 to 0.738 and from 0.306 to 0.913, respectively. Marker transferability was tested on other two Crassostrea species and polymorphic products were detected at nine loci. EST‐derived simple sequence repeats provide robust, informative and potentially transferable polymorphic markers suitable for population genetic, parentage, and mapping studies of C. gigas.  相似文献   

8.
Detailed studies on kin structure, mating patterns and dispersal in social insects require highly polymorphic markers, of which the most commonly used today are DNA microsatellites. Here we characterize 10 polymorphic microsatellite markers for the ant Plagiolepis pygmaea. We also investigated the within‐genus applicability of the markers on P. xene, a social parasite of the source species. In addition, we tested amplification of the markers in three species of the genera Formica and Lasius. Eight of the markers also amplified in P. xene and were polymorphic. Seven markers amplified in at least one other formicine ant.  相似文献   

9.
The house fly, Musca domestica L., is a cosmopolitan species with a capacity to transmit human pathogens. Here, we report on the development of polymorphic microsatellite loci for house flies and present preliminary results from four house fly subpopulations from Manhattan, Kansas. Twenty‐four microsatellite loci were isolated and characterized using DNA enriched for repeat sequences. Forty individuals from four locations in Kansas were assayed to identify for polymorphic loci. Eight loci were polymorphic with the number of alleles ranging from three to six.  相似文献   

10.
We describe 10 polymorphic tetranucleotide microsatellite loci from the eastern Canary Island lacertid lizard, Gallotia atlantica. Loci were isolated from a partial genomic library that had been enriched for AAAG repeat sequence. All loci were highly polymorphic (eight alleles or more) with observed heterozygosities from 0.75 to 1.00. At least four loci were successfully amplified and polymorphic in the Gran Canarian lacertid, Gallotia stehlini. These loci will be used to examine correlations between patterns of gene flow and recent volcanism on the island of Lanzarote.  相似文献   

11.
Reticulitermes termites have such a cryptic life style and complex colony structure that polymorphic microsatellite markers are desired to investigate their population and colony structures. We successfully isolated seven microsatellite loci in R. speratus , the Japanese subterranean termite, five of which were polymorphic. These polymorphic loci had 2–8 alleles per locus and their observed heterozygosities ranged from 0.059 to 0.438. These five loci were also polymorphic in R . kanmonensis , distributed sympatrically with R. speratus in the Kanmon Region, western Japan; the number of alleles per locus was 2–5, and observed heterozygosity was 0.176–0.625.  相似文献   

12.
Analysis of the blood protein system was used to study the genetic composition of Arabian horses. Biochemical markers of eight polymorphic loci (Tf, Al, As, AlB, Gc, Hb, PGD, and PGM) were electrophoretically identified in blood samples. A total of 43 phenotypes were identified for these polymorphic systems. The Tf, Hb, and Esloci appeared to be more polymorphic than the other loci studied. Statistically significant differences between the observed and expected genotypic frequencies were found for the PGDandPGMloci (P< 0.05 and P< 0.01, respectively). Individual allele frequencies, observed and expected phenotype frequencies, and the average heterozygosity were estimated for each polymorphic locus.  相似文献   

13.
The spectacled flying fox, Pteropus conspicillatus, is listed as vulnerable in Australia and is under threat from numerous impacts. Primers to amplify eight co-dominant microsatellite loci were designed for Pteropus conspicillatus, based on an enriched genomic library. Four loci were monomorphic in this species while the remaining four loci were highly polymorphic with 16–23 alleles. Two of the four monomorphic loci were found to be polymorphic in Pteropus alecto, a closely related congener. All but one of the six polymorphic loci were in Hardy Weinberg equilibrium. Additionally, six microsatellite loci isolated for Pteropus rodricensis were tested against individuals of P. conspicillatus with all loci amplifying reliably. These loci will be used to investigate population genetic structure in the vulnerable spectacled flying fox.  相似文献   

14.
Starch gel electrophoresis of 17 proteins has provided data on inter- and intrapopulation genetic variation in 20 species ofPorphyra occurring in British Columbia and adjacent areas.P. cuneiformis andP. nereocystis showed no within species variation, even over ranges of more than 1000 km. Populations ofP. abbottae, P. fallax, P. fucicola, P. gardneri andP. schizophylla were characterized by fixation for certain alleles. The number of polymorphic loci in a population ranged from zero to nine, depending on the species. Six species had populations that were polymorphic at just a single locus. Only two species (P. mumfordii andP. pseudolanceolata) had populations that were polymorphic at more than three loci. These levels of genetic variation are lower than those reported for populations of JapanesePorphyra species. Eleven taxa were polymorphic for 6-phosphogluconate dehydrogenase, the most variable enzyme. No within species polymorphisms were detected for bromoperoxidase, lactate dehydrogenase, superoxide dismutase or phycoerythrin. Possible evidence for the chimeric nature of the thallus was observed only inP. mumfordii.  相似文献   

15.
Fusarium circinatum is the causal agent of pitch canker disease of pines. This pathogen is thought to have originated in Central America and currently poses a serious threat to commercial pine plantations in many areas of the world. In this study, polymorphic molecular markers were developed for F. circinatum using the internal short sequence repeats‐polymerase chain reaction (ISSR‐PCR) technique. Nine sequence characterized amplified polymorphic markers were developed. Thirty‐two putative alleles were observed among 103 F. circinatum isolates from different geographical areas using the nine polymorphic markers. These sequence characterized amplified polymorphic markers can be used as genetic tools in populations studies of F. circinatum.  相似文献   

16.
The brook charr (Salvelinus fontinalis; Osteichthyes: Salmonidae) is a phenotypically diverse fish species inhabiting much of North America. But relatively few genetic diagnostic resources are available for this fish species. We isolated 41 microsatellites from S. fontinalis polymorphic in one or more species of salmonid fish. Thirty‐seven were polymorphic in brook charr, 15 in the congener Arctic charr (Salvelinus alpinus) and 14 in the lake charr (Salvelinus namaycush). Polymorphism was also relatively high in Oncorhynchus, where 21 loci were polymorphic in rainbow trout (Oncorhynchus mykiss) and 16 in cutthroat trout (Oncorhynchus clarkii) but only seven and four microsatellite loci were polymorphic in the more distantly related lake whitefish (Coregonus clupeaformis) and Atlantic salmon (Salmo salar), respectively. One duplicated locus (Sfo228Lav) was polymorphic at both duplicates in S. fontinalis.  相似文献   

17.
Twelve novel polymorphic microsatellite loci are presented for the dark bush cricket, Pholidoptera griseoaptera. All loci are polymorphic, with up to 37 alleles per locus. These microsatellites will be useful tools for studying the influence of landscape structure and land use intensity in agricultural landscapes on genetic diversity within and among populations of P. griseoaptera.  相似文献   

18.
Understanding how the genetic characteristics of parents influence reproductive output is central to predicting the dynamics of small, endangered populations. We conducted a breeding experiment to look at the paternal genetic effects on offspring sex, fertility and growth in the peafowl (Pavo cristatus). Microsatellite loci were developed to allow maternity assignment and thus to allow us to separate maternal from paternal effects. We found 19 polymorphic loci in our inbred, captive population, six of which were only slightly polymorphic (HE range: 0.04–0.70). The remaining 13 loci were polymorphic enough to determine maternity by exclusion in approximately 85% of offspring.  相似文献   

19.
Two monoclonal rat anti-MHC alloantibodies detect a polymorphic determinant expressed on the peripheral lymphocytes of normal human donors. The pattern of cytotoxicity observed with these antibodies correlated with theHLA type of the individual; no HLA-A-locus specificities showed significant associations, and all of the HLA-B-locus specificities showing significant association were members of the Bw6 supertype. Family studies established that the determinant detected by the monoclonal antibodies is linked toHLA. These studies therefore provide an alternative basis for the production of monoclonal antibodies to polymorphic HLA determinants based on the conservation of polymorphic MHC determinants between man and rats.  相似文献   

20.
After selective enrichment and differential hybridisation of Cot-1 DNA fractions of plants with and without polymorphic heterochromatic segments, a repetitive sequence (called Bds1) specific to the polymorphic chromosome segments of Brachycome dichromosomatica (Brachyscome dichromosomatica) was isolated. A single repeat unit of Bds1 is 92 bp long and is organised in tandem arrays at three different polymorphic segment sites on the chromosomes of cytodeme A2. Although all three sites showed extensive polymorphism between plants, the karyotypes of all analysed mitotic root cells were stable within a single plant. Electron microscopy revealed heavily condensed chromatin structures at the most obvious polymorphic site. The mechanisms that generate and maintain the observed chromosome structure polymorphisms are discussed. Received: 16 March 1999; in revised form: 28 September 1999 / Accepted: 11 November 1999  相似文献   

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