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1.
This entomological survey examines the spatial and seasonal distribution patterns of flea species infesting dogs in Spain. Bioclimatic zones covering broad climate and vegetation ranges were surveyed according to size. In a cross‐sectional spatial survey carried out from late May 2013 to mid‐July 2015, 1084 dogs from 42 different locations were examined. A total of 3032 fleas were collected and identified as belonging to the following species: Ctenocephalides felis (Siphonaptera: Pulicidae) (81.7%, 2476 fleas); Ctenocephalides canis (11.4%, 347 fleas); Pulex irritans (Siphonaptera: Pulicidae) (6.9%, 208 fleas), and Echidnophaga gallinacea (Siphonaptera: Pulicidae) (0.03%, one flea). Variables observed to have effects on flea abundance were animal weight, sex, length of hair and habitat. In the seasonal survey conducted from June 2014 to June 2015, 1014 fleas were collected from 239 dogs at 30 veterinary practices across Spain. Peaks in C. felis abundance were observed in early summer and late autumn, whereas high numbers of P. irritans and C. canis were recorded in autumn. Numbers of fleas detected in winter were low overall. Based on these findings, the present study updates the spatial and seasonal distributions of flea species in Spain and assesses the impacts of host and habitat variables on flea infestation.  相似文献   

2.
Host identity, habitat type, season, and interspecific interactions were investigated as determinants of the community structure of fleas on wild carnivores in northwestern Mexico. A total of 540 fleas belonging to seven species was collected from 64 wild carnivores belonging to eight species. We found that the abundances of some flea species are explained by season and host identity. Pulex irritans and Echidnophaga gallinacea abundances were significantly higher in spring than in fall season. Flea communities on carnivore hosts revealed three clusters with a high degree of similarity within each group that was explained by the flea dominance of E. gallinacea, P. simulans, and P. irritans across host identity. Flea abundances did not differ statistically among habitat types. Finally, we found a negative correlation between the abundances of three flea species within wild carnivore hosts. Individual hosts with high loads of P. simulans males usually had significantly lower loads of P. irritans males or tend to have lower loads of E. gallinacea fleas and vice‐versa. Additionally, the logistic regression model showed that the presence of P. simulans males is more likely to occur in wild carnivore hosts in which P. irritans males are absent and vice‐versa. These results suggest that there is an apparent competitive exclusion among fleas on wild carnivores. The study of flea community structure on wild carnivores is important to identify the potential flea vectors for infectious diseases and provide information needed to design programs for human health and wildlife conservation.  相似文献   

3.
Fleas represent an acknowledged burden on dogs worldwide. The characterization of flea species infesting kennel dogs from two localities in Israel (Rehovot and Jerusalem) and their molecular screening for Bartonella species (Rhizobiales: Bartonellaceae) was investigated. A total of 355 fleas were collected from 107 dogs. The fleas were morphologically classified and molecularly screened targeting the Bartonella 16S–23S internal transcribed spacer (ITS). Of the 107 dogs examined, 80 (74.8%) were infested with Ctenocephalides canis (Siphonaptera: Pulicidae), 68 (63.6%) with Ctenocephalides felis, 15 (14.0%) with Pulex irritans (Siphonaptera: Pulicidae) and one (0.9%) with Xenopsylla cheopis (Siphonaptera: Pulicidae). Fleas were grouped into 166 pools (one to nine fleas per pool) according to species and host. Thirteen of the 166 flea pools (7.8%) were found to be positive for Bartonella DNA. Detected ITS sequences were 99–100% similar to those of four Bartonella species: Bartonella henselae (six pools); Bartonella elizabethae (five pools); Bartonella rochalimae (one pool), and Bartonella bovis (one pool). The present study indicates the occurrence of a variety of flea species in dogs in Israel; these flea species are, in turn, carriers of several zoonotic Bartonella species. Physicians, veterinarians and public health workers should be aware of the presence of these pathogens in dog fleas in Israel and preventive measures should be implemented.  相似文献   

4.
The plant‐parasitic nematode Nacobbus aberrans sensu lato is an agricultural pest of quarantine importance. Due to the morphometric, physiological and genetic variability observed within the species, there is no agreement on the taxonomy of this nematode. The objective of this study was to analyse the ITS rDNA region and the D2–D3 expansion segments of 28S rDNA in 10 Argentine populations and one from Ecuador and to establish their phylogenetic relationship with other known sequences from South and North America. Phylogenetic trees of the ITS gene showed seven statistically well‐supported clades; the high and significant Fst values obtained among these groups confirmed this partitioning. The Argentine populations here considered were separated into three clades: one comprising a population from the Andean region and two grouping nematodes from lower altitudes. Three other clades were distinguished for South American populations, which included known sequences of individuals from Peru, Bolivia and north of Argentina. The other clade included sequences from Mexico, Ecuador and two Argentine populations of unknown origin. The important degree of genetic divergence observed among Andean populations suggests that the Andes may have played a crucial role in speciation of Nacobbus, which would have originated in this region. Although D2–D3 segments exhibited lower variation, they were useful for establishing phylogenetic relationships among the Argentine populations considered in this work. As there are no other GenBank sequences available for these segments, it was not possible to make comparisons with other populations from South and North America. The considerable genetic differentiation observed in ITS rDNA region among Nacobbus populations showed evidence of cryptic species within the N. aberrans s.l. complex. Integration of morphological and morphometric studies and molecular analyses considering other genes may aid in the identification of species and their phylogenetic relationships within this genus.  相似文献   

5.
The marine ascomycete genus Haloguignardia occurs endophytically in members of the marine brown algal family Sargassaceae globally. This example of endosymbiosis has been morphologically described: the fungal component internally infects the algal host resulting in prolific cell growth, forming galls composed chiefly of host algal cells but containing fungal reproductive structures and vegetative hyphae. H. irritans induces the formation of galls in the brown algae Cystoseira osmundacea and Halidrys dioica along the Pacific coast from Oregon to Baja California, Mexico. Using culture‐independent molecular techniques, I sequenced the 18S rDNA gene region for H. irritans and generated a 18S‐based taxonomy consistent with the current taxonomy for this morphological species. In order to study intraspecific genetic variation in H. irritans, I have sequenced the ITS rDNA (ITS 1, 2 and the 5.8 s) regions for five separate gall‐tissue samples from Santa Rosa Island in southern California and for five samples from Monterey and Carmel in central California. Intraspecific DNA sequence variation in the ITS regions of H. irritans reveals consistent sequence divergence between sites sampled. The fungal ITS regions for H. irritans total 613 bp in length and contain 40 synapomorphic characters for a total of 6.5% variation in informative loci between southern and central Californian sites. This value is similar to those found for the ITS and other gene regions previously used by researchers investigating species boundaries at the intraspecific level in symbiotic, terrestrial fungi. In addition to ITS 1, 2 and the 5.8 s gene regions, I am currently using the 5’ end of the EF1a coding region to construct intraspecific genealogies for H. irritans. By comparing these genealogies to each other and to the geographic distribution of samples, I aim to determine if more than one genetic species is present within the morphological species H. irritans.  相似文献   

6.
Fleas are a common cause of feline skin disorders as well as vectors of zoonotic diseases. This study evaluated the flea species infesting domestic cats in Spain and assessed factors influencing their distribution. Fleas from 217 cats from 57 localities in Spain were identified and associations between abundance, and host‐dependent, host habitat and environmental factors were examined. Variations in infracommunity and component community structure were also explored. Three species were present, of which Ctenocephalides felis (Bouché) (Siphonaptera: Pulicidae) was the most abundant (98.4%), followed by Ctenocephalides canis (Curtis) (1.1%) and Pulex irritans (L.) (Siphonaptera: Pulicidae) (0.5%). Overall abundance and abundances of both C. felis and C. canis were higher on farms than in apartments, but overall flea abundance and abundances of both C. felis and C. canis were lower in rural than urban environments. Overall abundance and C. felis abundance were lower during the warmest months, and mean annual rainfall was positively correlated with overall, C. felis and C. canis abundances. No relationship between the number of species per cat and any host, habitat or physiographical variable was found. Species richness was not correlated with mean annual temperature or rainfall. Flea abundance was mainly associated with host habitat and environmental factors.  相似文献   

7.
The worldwide spread of diseases is considered a major threat to biodiversity and a possible driver of the decline of pollinator populations, particularly when novel species or strains of parasites emerge. Previous studies have suggested that populations of introduced European honeybee (Apis mellifera) and bumblebee species (Bombus terrestris and Bombus ruderatus) in Argentina share the neogregarine parasite Apicystis bombi with the native bumblebee (Bombus dahlbomii). In this study we investigated whether A. bombi is acting as an emergent parasite in the non-native populations. Specifically, we asked whether A. bombi, recently identified in Argentina, was introduced by European, non-native bees. Using ITS1 and ITS2 to assess the parasite’s intraspecific genetic variation in bees from Argentina and Europe, we found a largely unstructured parasite population, with only 15% of the genetic variation being explained by geographic location. The most abundant haplotype in Argentina (found in all 9 specimens of non-native species) was identical to the most abundant haplotype in Europe (found in 6 out of 8 specimens). Similarly, there was no evidence of structuring by host species, with this factor explaining only 17% of the genetic variation. Interestingly, parasites in native Bombus ephippiatus from Mexico were genetically distant from the Argentine and European samples, suggesting that sufficient variability does exist in the ITS region to identify continent-level genetic structure in the parasite. Thus, the data suggest that A. bombi from Argentina and Europe share a common, relatively recent origin. Although our data did not provide information on the direction of transfer, the absence of genetic structure across space and host species suggests that A. bombi may be acting as an emergent infectious disease across bee taxa and continents.  相似文献   

8.
Flea identification is a significant issue because some species are considered as important vectors of several human pathogens that have emerged or re‐emerged recently, such as Bartonella henselae (Rhizobiales: Bartonellaceae) and Rickettsia felis (Rickettsiales: Rickettsiaceae). Matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF MS) has been evaluated in recent years for the identification of multicellular organisms, including arthropods. A preliminary study corroborated the usefulness of this technique for the rapid identification of fleas, creating a preliminary database containing the spectra of five species of flea. However, longterm flea preservation in ethanol did not appear to be an adequate method of storage in the context of specimen identification by MALDI‐TOF MS profiling. The goal of the present work was to assess the performance of MALDI‐TOF MS in the identification of seven flea species [Ctenocephalides felis (Siphonaptera: Pulicidae), Ctenocephalides canis, Pulex irritans (Siphonaptera: Pulicidae), Archaeopsylla erinacei (Siphonaptera: Pulicidae), Leptopsylla taschenbergi (Siphonaptera: Ceratophyllidae), Stenoponia tripectinata (Siphonaptera: Stenoponiidae) and Nosopsyllus fasciatus (Siphonaptera: Ceratophyllidae)] collected in the field and stored in ethanol for different periods of time. The results confirmed that MALDI‐TOF MS can be used for the identification of wild fleas stored in ethanol. Furthermore, this technique was able to discriminate not only different flea genera, but also the two congeneric species C. felis and C. canis.  相似文献   

9.
Two new species of flea of the genus Plocopsylla, subgenus Plocopsylla, (Siphonaptera: Stephanocircidae) collected from sigmodontine rodents in northwestern Argentina are described and a key to identification of species of the genus Plocopsylla, subgenus Plocopsylla, in Argentina is presented. Plocopsylla (P.) inti is cited for the first time in Argentina, extending its distribution ~ 970 km further south than previously documented. New locality data and flea–host associations are recorded. The contributions of this study are relevant because they increase knowledge of the diversity of flea fauna in northwestern Argentina bordering a plague endemic area and will be useful in the implementation of plague control management plans in the future.  相似文献   

10.
Dincă V  Dapporto L  Vila R 《Molecular ecology》2011,20(18):3921-3935
Widespread species have the potential to reveal large‐scale biogeographical patterns, as well as responses to environmental changes possibly unique to habitat generalists. This study presents a continental‐scale phylogeographical analysis of Polyommatus icarus, one of the most common Palaearctic butterflies, and the morphologically and ecologically similar Polyommatus celina, a recently discovered cryptic species. By combining data from mitochondrial [cytochrome c oxidase subunit I (COI)] and nuclear [internal transcribed spacer (ITS2)] molecular markers with geometric morphometrics, we document a complex phylogeographical history for the two species. Despite morphological similarities, the genetic divergence between these two species is high (more than 5% at COI) and they are not sister species. For the first time, we show that P. celina occurs not only in North Africa but also in Europe, where it inhabits several west Mediterranean islands, as well as large parts of Iberia, where it occurs in parapatry with P. icarus. The two species appear to completely exclude each other on islands, but we provide morphological and molecular evidence that introgression occurred in the Iberian Peninsula. We discovered strongly diverged lineages that seem to represent relict populations produced by past range expansions and contractions: Crete and Iberian isolates for P. icarus, Balearics–Sardinia and Sicily–Lipari for P. celina. This study shows that a combined genetic‐morphometric approach can shed light on cryptic diversity while providing the necessary resolution to reconstruct a fine‐scale phylogeographical history of species at both spatial and temporal levels.  相似文献   

11.
Aim This paper reports the presence of Artemia franciscana ( Kellogg, 1906 ) in Mar Chiquita (CHI) salt lake and in Las Tunas (TUN) lagoon, as well as at a shallow lake in Salinas Grandes (Province of Córdoba) in Argentina. To date, this species has been considered absent from Argentina. This study also provides further data on the characterization of the A. franciscana populations from this area. Location Province of Córdoba (Argentina). Methods The cyst samples collected at the three hypersaline environments were measured to assess its mean diameter with a dissecting microscope. The length of the nauplii hatched from the cysts was also determined with the microscope. The adults raised from these nauplii under strictly controlled conditions were analysed for 12 morphological parameters and compared through multivariate discriminant analysis with other American populations. Fatty acids from the total lipids were analysed by gas chromatography. Reproductive compatibility was evaluated from single‐pair intraspecific and interspecific crosses of adult specimens. Results The results endorse the morphometric assimilation of the Artemia populations of this area to other American populations of the A. franciscana‘super‐species’, together with its morphometric differentiation from the species A. persimilis ( Piccinelli & Prosdocimi, 1968 ). The more conspicuous population from CHI shows cross‐fertility with A. franciscana original from San Francisco Bay (California, USA). Both populations from CHI and TUN show cross‐fertility between them and reproductive isolation with A. persimilis from Hidalgo (Province of La Pampa), which to date is considered to be endemic or exclusive of hypersaline ecosystems in Argentina. The reproductive characteristics displayed by the population from TUN lagoon suggest the existence of an occasional hybridization between A. franciscana and A. persimilis ( Papeschi et al., 2000 ). Artemia cysts from CHI and TUN show a fatty acid profile rich in eicosapentaenoic acid differing markedly from the fatty acid profiles found in A. persimilis cysts. Main conclusions: Artemia franciscana is present in Argentina at 36° S and north of this latitude. Artemia persimilis is confined to the south of latitude 37°10′ S. There are different pieces of evidence that point to a certain level of hybridization of the two species taking place in the land belt between these parallels.  相似文献   

12.
Species of Philornis Meinert, 1890 (Diptera, Muscidae) are Neotropical dipterans that include species with parasitic larvae which feed on nestling birds. To date, all Philornis species that have been recorded from Argentina have parasitic subcutaneous larvae. Here, for the first time for Argentina, we report the finding of Philornis downsi Dodge & Aitken, 1968, a fly with a nest-dwelling, semi-haematophagous larva. This record, from the humid Chaco ecoregion of Argentina in the nest of a saffron finch Sicalis flaveola pelzelni Sclater, substantially extends the known distribution of this species. We also report the consensus sequences of the internal transcribed spacer 1 (ITS1) and ITS2 regions of three of the specimens for future reference and comparison. Further investigation is needed to determine whether Argentina is part of the historical range of P. downsi or, alternatively, represents a recent expansion of its range, perhaps due to climatic changes or other factors of global environmental variation.  相似文献   

13.
The role of red fox as host for a wide range of parasites, particularly fleas and other arthropods causing vector-borne diseases, in combination with its capability to adapt to anthropized environments, makes this wild canid an epidemiologically remarkable species at the wildlife–domestic–human interface, especially in the present time of rise of emerging and re-emerging diseases. This study evaluated the prevalence and parasite intensity of fleas in 88 foxes from Murcia Region (Southeastern Spain) and determined the geographic distribution of areas with the highest potential risk of flea presence. Pulex irritans, Ctenocephalides felis, Spilopsyllus cuniculi and Nosopsyllus fasciatus were identified. The overall prevalence was 76.13%. This is the first time that N. fasciatus has been reported in foxes from Murcia Region. The predictive model established a certain pattern to determine the areas with the highest risk of acquiring fleas. Positive correlation of daily potential evapotranspiration (ET0) in winter and the opposite effect occurring for ET0 in summer were obtained, as well as positive correlations for mean daily temperature (Tmean) in summer and mean precipitation (Pmean) in winter and summer. The model was also found positively correlated in the forest habitat ecotone areas and the anthropized areas.  相似文献   

14.
The phylogenies of all eight European species of Philaenus were estimated from cytochrome oxidase subunit I, cytochrome B and internal transcribed spacer 2 (ITS2) fragments of DNA using phylogenetic reconstruction methods: maximum parsimony (MP), maximum likelihood (ML) and Bayesian inference (BI) analyses. Based on the topologies of all obtained phylogenetic trees, the monophyly of Philaenus is well supported, being congruent with morphological, ecological and chromosomal data. Three phylogenetic lineages were distinguished in the mitochondrial and combined (mtDNA with ITS2) trees. The first lineage is represented by only one species, Philaenus maghresignus, which inhabits Maghreb and southern Spain. Clade A includes three species: P. tarifa (Southern Iberia), P. italosignus (Sicily and Southern Italy) and P. signatus (the Balkans and Middle East). In clade B two subclades were recognized: B1 represented by P. loukasi (Southern Balkans) and P. arslani (Middle East), and B2 comprising P. spumarus (the most widespread Palaearctic species) and P. tesselatus (from Southern Iberia and Maghreb). These clades were also retrieved in trees reconstructed from nuclear sequences. However, four species (P. maghresignus, P. tarifa, P. italosignus and P. signatus) showed unresolved polytomy at the base of the nuclear tree. Clade A together with P. maghresignus clustered with the ‘signatus’ group defined from morphology, and clade B with the ‘spumarius’ group; these might be considered separate subgenera. Genetic distances in mitochondrial DNA between ingroup species ranged from 14.0% between P. signatus and P. spumarius to 2.4% between P. tesselatus and P. spumarius. By contrast, genetic divergence of ITS2 between ingroup species was very low, at most 2.1%. The divergence of Philaenus species is estimated to have occcurred between 7.9 and 0.6 Ma. Possibly three main speciation events occurred: the first at the Miocene/Pliocene boundary (c. 5.5 Ma) for deeper splits; the second between 4.2 and 2.5 Ma in the Pliocene, when pairs of more closely related species diverged; and the most recent during the Pleistocene glaciations, when the separation of P. tesselatus and P. spumarius took place. The species status of all Philaenus species is confirmed except for P. tesselatus.  相似文献   

15.
Fifteen populations of the widespread fieshwater red alga Batrachospermum gelatinosum (L.) De Candolle were sampled throughout the geographic range in North America from central Alabama, U.S.A. (33° N), to Ellesmere Island, Northwest Territories (NWT), Canada (80° N). Analysis of ribosomal DNA internal transcribed spacer (ITS) 1 and 2 sequences yielded a parsimony tree with a large polytomy consisting of most populations plus a branch with one Nova Scotia and two NWT populations. The nucleotide variation, both within the polytomy and within the branch, was small (< 1%). The sequence divergence between the branch and polytomy was 3%. The lengths of the ITS 1 and 2 sequences of B. gelatinosum, 216–229 and 448–458 base pairs, respectively, fall within the very broad ranges reported for other red algae. The cluster analysis of 11 morphometric characteristics revealed three groupings of populations, partly based on geographic distribution. All tundra, eastern boreal forest, and mid-western hemlock-hardwood populations were in one grouping, whereas the deciduous forest, coastal plain, and eastern hemlock-hardwood populations were in a second. How ever, one deciduous forest population from Rhode Island, U.S.A. was unassociated. There was considerable overlap in morphometric characteristics among the three groupings. Based on this fact and the relatively small nucleotade variation in ITS sequences, we conclude that B. gelatinosum is a morphologically variable and geographically widespread species that is a valid taxonomic entity.  相似文献   

16.
Sooretamys is a monotypic genus of the family Cricetidae, subfamily Sigmodontinae, that is distributed throughout eastern South America in the Atlantic Forest Biome, including Argentina, Brazil, and Paraguay. The taxonomic history of the forms associated with this genus is long and relatively complex, and few studies have evaluated the taxonomic problems of this genus. To this end, our goal was to describe the degree and geographical pattern of morphological and molecular variation in this genus to test the current hypothesis that the genus is monotypic, and, as a consequence, to determine the status of the nominal forms associated with Sooretamys. Accordingly, we employed morphometric, morphological, and molecular tools, according to an integrative taxonomy approach. The results show that some level of morphometric discontinuity is present between the individuals from Paraguay and those from adjacent localities in Brazil and Argentina; sharp discontinuities were not observed in qualitative traits. Molecular analyses of the mitochondrial cytochrome b gene showed that the Paraguayan populations have some degree of genetic differentiation, but the haplotypic variants do not form a monophyletic group. Thus, the evidence so far suggests a difference in the genes and morphology of the Paraguayan population, but there is no consistent resolution (e.g. lack of monophyly) to show that specimens from Paraguay represent a distinct population that would merit taxonomic recognition. Thus, we recognize a single species within the genus Sooretamys, named Sooretamys angouya. The pattern of morphological and genetic differentiation of Sooretamys could be the result of divergence with gene flow. However, our data also correspond in some aspects with the model advanced by Carnaval & Moritz, which claims the existence of stable Atlantic Forest areas where the forest biota persisted during the Quaternary climatic fluctuations. Whatever process has occurred, S. angouya represents one species with a complex evolutionary history, and the analysis of additional samples would be welcome to further elucidate the process of diversification of this taxon. © 2014 The Linnean Society of London  相似文献   

17.
We report on two new lineages of the Eumida sanguinea complex from Great Britain and describe one of them as a new species using a multilocus approach, including the mitochondrial DNA COI-5P and the nuclear markers ITS (ITS1, 5.8S rRNA and ITS2) and 28S rRNA. The molecular analysis placed Eumida mackiei sp. nov. in a monophyletic clade with 19.1% (COI), 10.1% (ITS) and 1.7% (28S) mean distance to its nearest neighbour. Molecular diagnoses were also applied to nine lineages within the E. sanguinea complex. This was complemented with morphometric data employing multivariate statistical analysis and the incorporation of statistical dissimilarities against three other described species from the complex. Eumida mackiei sp. nov. can be distinguished from E. notata and E. maia by the larger distance between the eyes and differences in morphometric proportions mainly in the dorsal and ventral cirri as well as in the prostomial appendages. E. sanguinea sensu stricto failed to produce a cluster of its own in the morphometric analysis, probably due to juvenile bias. Integrative taxonomy provided strong evidence to formally describe a new cryptic species that can now be used in biomonitoring or other relevant ecological research.  相似文献   

18.
A total of 559 fleas representing four species (Pulex irritans, Ctenocephalides felis, Ctenocephalides canis and Spilopsyllus cuniculi) collected on carnivores (five Iberian lynx Lynx pardinus, six European wildcat Felis silvestris, 10 common genet Genetta genetta, three Eurasian badger Meles meles, 22 red fox Vulpes vulpes, 87 dogs and 23 cats) in Andalusia, southern Spain, were distributed in 156 pools of monospecific flea from each carnivore, and tested for Bartonella infection in an assay based on polymerase chain reaction (PCR) amplification of the 16 S–23 S rRNA intergenic spacer region. Twenty‐one samples (13.5%) were positive and the sequence data showed the presence of four different Bartonella species. Bartonella henselae was detected in nine pools of Ctenocephalides felis from cats and dogs and in three pools of Ctenocephalides canis from cats; Bartonella clarridgeiae in Ctenocephalides felis from a cat, and Bartonella alsatica in Spilopsyllus cuniculi from a wildcat. DNA of Bartonella sp., closely related to Bartonella rochalimae, was found in seven pools of Pulex irritans from foxes. This is the first detection of B. alsatica and Bartonella sp. in the Iberian Peninsula. All of these Bartonella species have been implicated as agents of human diseases. The present survey confirms that carnivores are major reservoirs for Bartonella spp.  相似文献   

19.
20.
We investigated the genetic variations of the samples that were tentatively identified as two cultivated Porphyra species (Porphyra yezoensis Ueda and Porphyra tenera Kjellm.) from various natural populations in Japan using molecular analyses of plastid and nuclear DNA. From PCR‐RFLP analyses using nuclear internal transcribed spacer (ITS) rDNA and plastid RUBISCO spacer regions and phylogenetic analyses using plastid rbcL and nuclear ITS‐1 rDNA sequences, our samples from natural populations of P. yezoensis and P. tenera showed remarkably higher genetic variations than found in strains that are currently used for cultivation. In addition, it is inferred that our samples contain four wild Porphyra species, and that three of the four species, containing Porphyra kinositae, are closely related to cultivated Porphyra species. Furthermore, our PCR‐RFLP and molecular phylogenetic analyses using both the nuclear and plastid DNA demonstrated the occurrence of plastid introgression from P. yezoensis to P. tenera and suggested the possibility of plastid introgression from cultivated P. yezoensis to wild P. yezoensis. These results imply the importance of collecting and establishing more strains of cultivated Porphyra species and related wild species from natural populations as genetic resources for further improvement of cultivated Porphyra strains.  相似文献   

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