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1.
The yellow‐flowered everlasting daisy Helichrysum italicum (Asteraceae, Gnaphalieae) is widely distributed in the Mediterranean basin, where it grows in continuous and widespread populations in diverse open habitats. Helichrysum italicum subsp. microphyllum has a disjunct distribution in the Balearic Islands (Majorca and Dragonera), Corsica, Sardinia, Crete and Cyprus. Numerous morphological intermediates between subsp. italicum and subsp. microphyllum are known from Corsica, where the two subspecies co‐occur. The aims of the study were to investigate if subsp. microphyllum has a common origin, constituting an independent gene pool from subsp. italicum, or if the morphological differences between subsp. microphyllum and subsp. italicum have arisen independently in different locations from a common wider gene pool. Our analyses of AFLP, cpDNA sequences and morphological characters show that there is geographic structure to the genetic variation within H. italicum, with eastern and western Mediterranean groups, which do not correspond with the division into subsp. microphyllum and subsp. italicum as currently circumscribed. Local selection on quantitative trait loci provides sufficient explanation for the morphological divergence observed and is consistent with genetic data. Within the western Mediterranean group of the species we found considerable polymorphism in chloroplast DNA sequences among and within some populations. Comparison with chloroplast DNA sequences from other Helichrysum species showed that some chloroplast haplotypes are shared across species.  相似文献   

2.
The Helichrysum occurrences spread over Hyblaean area (Sicily) are characterized by an unusual richness of morphotype variants which ancestral origin is still unclear. Morphological and genetic variability of seven populations attributable to six taxonomic entities (Helichrysum archimedeum, H. stoechas subsp. conglobatum, H. stoechas subsp. barrelieri, H. hyblaeum, H. pendulum and H. nebrodense) was examined, in order to highlight their relationships within the Helichrysum sect. Stoechadina. Morphological analysis showed a clear isolation of populations referred to H. pendulum, H. nebrodense and H. stoechas subsp. conglobatum. Whereas, genetic structure profiling, with 21 ISSRs, displayed a strong genetic relationship within H. stoechas and H. archimedeum accessions, where the latter exhibited evident genetic similarity with H. hyblaeum. Analysis of rbcL cpDNA fragment allowed to identify a shared haplotype between H. stoechas and H. rupestre species, while, through the construction of haplotype network based on trnL-F/rpl32 region, the sampled accessions were properly differentiated as confirmed by the cpDNA consensus network. These results confirmed the high affinity of H. archimedeum with other H. stoechas populations and the closer relationship of H. hyblaeum to H. stoechas respect to H. rupestre.  相似文献   

3.
Helichrysum Mill. (Asteraceae) species have been used in folk medicine for thousands of years in the world. The in vitro cytogenetic effects in human lymphocytes of nine Helichrysum taxa used in Turkey folk medicine were investigated. Blood samples were obtained from healthy donors, non-smoking volunteers, which were incubated and exposed to increasing concentrations of methanol extracts of Helichrysum taxa (0.01, 0.05, 0.1, 0.5 and 1 mg/mL). The inhibitory effects of H. stoechas (L.) Moench subsp. barrelieri (Ten.) Nyman, H. armenium DC. subsp. armenium, H. armenium DC. subsp. araxinum (Kirp.) Takht., H. plicatum DC. subsp. plicatum, H. compactum Boiss. and H. artvinense P.H.Davis & Kupicha on the mitotic index and replication index indicate that these taxa can have genotoxic and mutagenic effects. They should therefore not be used freely in alternative medicine although their antiproliferative activity may suggest anticarcinogenic properties. Increase effects of H. stoechas subsp. barrelieri, H. armenium subsp. armenium, H. armenium subsp. araxinum, H. chasmolycicum P.H.Davis, H. plicatum subsp. plicatum, H. compactum and H. artvinense on the micronucleus rates showed that these taxa can have genotoxic and carcinogenic effects.  相似文献   

4.
Helichrysum nicolai from the Cape Verdean island of São Nicolau is described as a species new to science and illustrated. The systematic position in Helichrysum of this acaulescent dwarf rosette shrub with heterogamous capitula, in which the female flowers outnumber the hermaphrodite ones, is established using an ITS phylogeny based on maximum parsimony and Bayesian inference analyses. The new species is most closely related to the Canary Island endemics H. alucense and H. monogynum. The closest relative to these three species are not the other members of the genus on the mid-Atlantic archipelagos but H. somalense from the Horn of Africa region and the southern Arabian Peninsula and the widespread tropical African-S Arabian-SE Iranian H. glumaceum, to which the SE Iranian H. makranicum is found to be conspecific. The phytogeographical significance of these relationships is discussed and at least three independent colonization events of the mid-Atlantic archipelagos by Helichrysum are concluded from the molecular data available.  相似文献   

5.
The species of Gnaphalium, Helichrysum and related genera in southern Africa have been surveyed and a number of groups of allied species detected in which the ratio of female to hermaphrodite flowers ranges from a majority of female to a majority of hermaphrodite and in some groups there are even homogamous species. Thus, the failure of the old sex-ratio character used to separate Gnaphalium and Helichrysum is confirmed. The validity of these groupings has been tested by studying detailed characters such as the structure of the stereome (whether undivided or fenestrated) and the type of achenial hair, as well as the more usual floral characters. Most of these plants have leaves with flat or revolute margins and the occasional occurrence of involute margins is taxonomically important. Gnaphalium L. (type G. uliginosum L.) has been redefined to include Amphidoxa DC. and Demidium DC. (female flowers epappose) and species with more hermaphrodite flowers then female. The stereome is undivided. Helichrysum remains a massive and highly diverse genus and includes Leontonyx Cass. The stereome is normally fenestrated and the receptacle epaleate. One or two species have paleae, but Rhynea with receptacle paleate and stereome undivided is maintained. A small group of species with undivided stereomes, centred on H. marifolium D.C., has had to be retained in Helichrysum because of the existence of linking species. Undivided stereome and subglobose achenial hairs enjoin the transfer of H. vestitum (L.) Willd. and two allies, as well as the group of species centred on H. paniculatum (Thunb.) Thunb., to Helipterum, despite the lack of plumose pappus. Edmondia Cass. (H. sesamoides (L.) Willd.) with distinctive habit, involute leaves and no close relatives in Helichrysum is reinstated. Pseudognaphalium Kirp., to which only P. oxyphyllum (DC.) Kirp. had previously been assigned, is extended to include, in its typical subgenus, Hypelichrysum Kirp. and a number of American species of Gnaphalium, as well as the African G. undulatum L. and G. oligandrum (DC.) Hilliard & Burtt, and the Asiatic G. hypoleucum DC. and G. chrysocephalum Franch. A new subgenus, Laphangium, is created to accommodate G. luteo-album L. and its allies. Achyrocline (Less.) DC. has been maintained, as is done in South America, and some African species placed under Helichrysum by Moesert 1910) are returned to it. Two new genera are recognized among gnaphalioid plants with undivided stereomes: Troglophyton (based on G. capillaceum Thunb.) with about seven species and Plecostachys (based on G. serpyllifolium Berg, and including G. polifolium Thunb.). Both genera straddle the old numerical boundary between Gnaphalium and Helichrysum. The monotypic Helichrysopsis Kirp. is maintained. Plants of gnaphalioid aspect with fenestrated stereomes necessitate a further new genus: Vellereophyton (type G. dealbatum Thunb., better known as G. candidissimum Lam.) with seven species. Eriosphaera Less, and Lasiopogon Cass, are redefined and enlarged to include species previously placed in Gnaphalium. Metalasia and Lachnospermum are redefined, with the transfer of the only large-headed species remaining in Metalasia to Lachnospermum. Two new genera are created for plants in this affinity previously misplaced in Helichrysum. Atrichantha is based on H. gemmiferum Bol. and one new species is described. Dolichothrix is established for the anomalous H. ericoides (Lam.) Pers. Ifloga is briefly investigated and it is shown that the distinction between sect. Ifloga and sect. Eutrichogyne Bentham must be based on characters of the capitulum, not just on annual versus subshrubby habit. Lasiopogon molluginoides DC. (=Comptonanthus Nordenstam) is transferred to Ifloga and the structure of the capitulum in the genus is discussed. Some earlier work on this group of plants is briefly summarized, the phytogeographical interest of the proposed arrangement is discussed and some general conclusions offered.  相似文献   

6.
In the framework of our studies on Lamiaceae from the eastern Iberian Peninsula, for the forthcoming fourth volume of Flora valentina, a new infraspecific arrangement is proposed here for the Iberian endemic Teucrium thymifolium. Besides the type subspecies, T. thymifolium subsp. thymifolium, which is widely distributed through the eastern Iberian Peninsula, two new nomenclatural combinations are established: (i) T. thymifolium subsp. fraternum (Pau) M.B. Crespo, M.A. Alonso & Mart.-Azorín (= T. terciae), for the thermophilous populations growing in SE Murcia province, and (ii) T. thymifolium subsp. hervieri (Briq. & Debeaux) M.B. Crespo, M.A. Alonso & Mart.-Azorín, for Subbaetic inland populations from where the provinces of Albacete, Jaén and Granada come into contact. Nomenclatural types and data on distribution and ecology are reported for all accepted subspecies, including the designation of a lectotype for T. thymifolium subsp. hervieri. Furthermore, relationships of the latter to the recently described T. moleromesae Sánchez Gómez et al. are briefly discussed, both taxa being treated here in synonymy.  相似文献   

7.
 The genetic variation of 102 natural populations of wild barley growing in Spain was assessed using RAPDs (random amplified polymorphic DNA). The plant material included the annual species H. marinum subsp. marinum (22 populations) and subsp. gussoneanum (14), H. murinum subsp. murinum (7) and subsp. leporinum (35), and the perennial species H. bulbosum (17) and H. secalinum (7). Ten of the tested 64 arbitrary 10-mer primers amplified polymorphic DNA in all taxonomic units. Analyses was performed within and between populations, species and subspecies. The primers gave a total of 250 RAPD products. The level of polymorphism varied between taxonomic units depending on the primers employed and the plant reproductive system. In general, the most variable were the allogamous species H. secalinum and H. bulbosum and the autogamous H. marinum subsp. marinum. Among the amplified bands, 69 (27%) were shared by at least two different taxonomic units. The remaining bands were specific. The results demonstrate differences in the degree of similarity between taxonomic units. Jaccard’s similarity coefficients for interval measure within and between populations were used to produce a cluster diagram using the unweighted pair-group method (UPGMA). The different populations of the species and subspecies of Hordeum fell into three groups. The first group contained the populations belonging to both subspecies of H. marinum, plus those of H. secalinum. The populations of H. marinum subsp. gussoneanum were very closely associated. Those of H. marinum subsp. marinum were grouped in a broad cluster. The second group, occupying the innermost position of the tree, was very closely associated with the populations of both subspecies of H. murinum. The third branch segregated H. bulbosum. A series of RAPD markers were investigated by cleaving the amplified products of the same size with restriction endonucleases that recognize targets of 4- or 6-bp. The production of equivalent fragments following cleavage by the same enzyme would seem to demonstrate their homology in samples from different individuals, populations or taxonomic units. Received: 18 May 1997 / Accepted: 22 August 1997  相似文献   

8.
  • Helichrysum microphyllum subsp. tyrrhenicum (Asteraceae) is an endemic taxon of Sardinia and Corsica, where it grows at different altitudes. The objective of this study was to investigate the seed traits and germination behaviour of four Sardinian populations of this taxon located at different altitudes.
  • Seed traits were evaluated, and germination tests were carried out by incubating seeds at a range of constant (5–30 °C) and alternating (25/10 °C) temperatures. The dry after‐ripening (DAR) pre‐treatment was also applied by storing seed in dry conditions for 3 months at 25 °C. Seed traits and germination behaviour data were statistically analysed to identify if there was a correlation with altitude.
  • Differences in seed size, area and mass among populations were recorded, however, no relationship was found with altitude. High germination percentages were obtained in all populations, both in untreated and DAR seeds, and were positively affected by alternating temperatures. The final germination percentage and time required to reach 50% final germination (T50) showed no relationship with altitude.
  • The differences in seed traits and germination detected among the studied populations of H. microphyllum subsp. tyrrhenicum were not correlated with altitude. This study provides new and important knowledge for this taxon. H. microphyllum subsp. tyrrhenicum is characterised by high germination percentages and low T50 values and does not seem to require any dormancy‐breaking treatment. This species represents a high‐potential native plant species that should be considered within environmental management plans.
  相似文献   

9.
Strict sterility barriers where found between theScutellaria populations on Sicily and the Greek populations. The material from Samos is separated by a strict sterility barrier from the other Greek populations. In contrast, the populations on mainland Greece and adjacent islands are all ± interfertile. Three species are recognized,S. rubicunda Hornem., endemic to Sicily, andS. brevibracteata subsp.icarica, endemic to Samos and Ikaria. All other populations are referred toS. rupestris with eight subspecies, most of which are endemic to one island or to one mountain. Three new subspecies are described, viz. subsp.rechingeri and subsp.olympica, endemic to mt Vourinos and mt Olympus in North Greece, respectively, and subsp.caroli-henrici, native to the Malea peninsula of Peloponnisos. The phytogeographical connections and genetic differentiation within and between populations are discussed.Dedicated to Prof. DrK. H. Rechinger on the occasion of his 80th birthday.  相似文献   

10.
Dactylorhiza majalis subsp. sphagnicola is an allotetraploid marsh orchid derived from parents closely similar to present‐day D. incarnata and the western European form of D. maculata subsp. maculata, suggesting that it has a postglacial origin. It extends from northwestern continental Europe into areas formerly covered by the Weichselian ice sheet in mid‐Scandinavia. Here, we studied the variation at both the plastid and nuclear marker systems to describe the geographical variation in subsp. sphagnicola and its evolutionary history. We investigated whether subsp. sphagnicola is affected by secondary hybridization and gene flow from its parental lineages or from other allotetraploid marsh orchids, and we also compared subsp. sphagnicola with other allotetraploids of similar origins. We analysed 492 plants from 50 populations. Thirty‐seven populations were collected as potential Dactylorhiza majalis subsp. sphagnicola, five as subsp. sesquipedalis (D. elata), one as D. elata subsp. brennensis, one as subsp. calcifugiens, one as subsp. occidentalis and the remaining five as populations with some affinity to subsp. lapponica (including D. traunsteineri). All populations were analysed for plastid haplotypes and nuclear internal transcribed spacer (ITS) allele frequencies, and a subset of 43 populations was analysed for five nuclear microsatellite loci. Dactylorhiza majalis subsp. sphagnicola was dominated by a single plastid haplotype that was also dominant in western European D. maculata subsp. maculata, and most of the alternative haplotypes differed by only one mutation from the dominant one. There was more variation in nuclear microsatellites and ITS, and the variation was geographically structured in these markers. Subspecies occidentalis and calcifugiens shared haplotypes with subsp. sphagnicola, whereas subsp. sesquipedalis and brennensis had other haplotypes. Dactylorhiza majalis subsp. sphagnicola may have a postglacial origin within its present continental distribution. It has incorporated genetic material from D. maculata subsp. maculata by secondary hybridization and introgression, and some northern populations have assimilated strongly divergent haplotypes from the northeastern form of D. maculata subsp. maculata. Subspecies sphagnicola has also evolved morphologically divergent local populations in the north that do not differ from the typical populations in genetic markers. It may form mixed populations with other allotetraploid subspecies of D. majalis and, at least at one site, it has become integrated with subsp. lapponica, demonstrating that independently derived allotetraploids may contribute to a common gene pool. Subspecies calcifugiens seems to be derived from subsp. sphagnicola, and further studies based on a larger sample may confirm that it is better recognized as a variety. The so‐called D. elata subsp. brennensis is of hybrid origin and combines markers from subsp. sesquipedalis with markers from the D. majalis core complex, possibly subsp. majalis. The new combination Dactylorhiza majalis subsp. sesquipedalis (Willd.) H.A.Pedersen & Hedrén comb. nov. is provided. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, 168 , 174–193.  相似文献   

11.
Polymorphism analyses of the hordeins, main storage proteins in barley, were conducted on 35 natural populations of Hordeum murinum s.l. from North Africa; this specific complex includes three subspecies with two ploidy levels: H. murinum subsp. glaucum (2n=2x=14), H. murinum subsp. leporinum and subsp. murinum (2n=4x=28). Twenty of these populations belong to the diploid subsp. glaucum, 14 other tetraploid populations belong to the subsp. leporinum. In addition, six populations of the tetraploid murinum were sampled in France: two along the Mediterranean coast and four in Brittany. The polymorphism observed in the electrophoretic patterns highlights strong correlations between bioclimatic features and di- and tetraploid taxa distribution. Moreover, the variation was not randomly distributed within the different ploidy levels, and is correlated with environmental factors. The ecological differentiation of the two main taxa, H. murinum subsp. leporinum and subsp. glaucum is clearly highlighted.  相似文献   

12.
Abstract

The Italian populations of Koeleria splendens C. Presl, critical group of the Mediterranean flora, are examined from the taxonomic and nomenclatural viewpoints. On the basis of literature data, herbarium investigations and field surveys, many morphologically well-differentiated taxa have been recognized. This group is widespread in the Italian peninsula and Sicily, where it is represented by the following units: K. splendens C. Presl, with four subspecies [subsp. splendens, subsp. grandiflora (Bertol. ex Schultes) Domin, subsp. brutia Brullo, Gangale & Uzunov, and subsp. ophiolitica subsp. nova], K. lucana sp. nova, K. subcaudata (Ascherson & Graebner) Ujhelyi, K. australis Kerner, K. callieri (Domin) Ujhelyi, and K. insubrica sp. nova. As concerns their distribution, both K. splendens and K. lucana are endemic to the Italian territory, while the other species occur also in some eastern Mediterranean countries. The taxonomic position of K. lobata, recently treated by some authors as a synonym of K. splendens, is also examined. A phylogenetic analysis was performed using morphological characters. Finally, a detailed iconography of the main morphological features and an analytical key of the Italian taxa (K. lobata included) are given.  相似文献   

13.
The chemical composition of epicuticular waxes of nine populations from three Pinus nigra J. F. Arnold subspecies (namely subsp. nigra, subsp. banatica (Borbás ) Novák , and subsp. pallasiana (Lamb .) Holmboe ) from Southern Carpathians and central Balkan Peninsula were analyzed using GC/MS and GC/FID chromatography, and multivariate statistical techniques with respect to biogeography and taxonomy. In the needle waxes, four primary alcohols and 14 n‐alkanes ranging from C21 to C33 were identified, and the most abundant compounds were the four odd‐numbered n‐alkanes C27, C25, C23, and C29. Multivariate statistical analyses (CDA and CA) have shown existence of three P. nigra groups and suggested clinal differentiation as a mechanism of genetic variation across a geographic area: the first group consisted of the southernmost populations of subsp. pallasiana from Macedonia, the second consisted of the northernmost subsp. banatica populations from Romania, while all populations in Serbia described as three different subspecies (nigra, banatica, and pallasiana) formed the third group together with subsp. nigra population from Bosnia and Herzegovina. According to simple linear regression, geographic latitude and four bioclimatic parameters were moderately correlated with the contents of epicuticular wax compounds that are important in population discrimination, while stepwise multiple regression showed that latitude participated in most of the regression models for predicting the composition of the epicuticular waxes. These results agree with CDA and CA analysis, and confirmed the possibility of recognition of fine geographic differentiation of the analyzed P. nigra populations.  相似文献   

14.
Abstract

Some taxa of Sicilian Helichrysum related to sect. Stoeachadina have an uncertain systematic position; moreover, they are rare and endangered. In order to preserve these taxa in a genebank, a strategy to keep their genetic variation as high as possible is required. The high informative content of AFLP markers was used to assess genetic variations within and between populations and their relationships. The results show that all populations are genetically similar, even though there are two distinct groups: the first is the population referred to H. pendulum, and the second is represented by other populations belonging to several different specific and intraspecific taxa. The H. pendulum population is homogeneous, and characterised by the lowest genetic variation among all the populations considered. The second group shows a greater variation as evidenced by the presence of three subgroups: (i) populations referred to H. panormitanum var. panormitanum and H. panormitanum var. stramineum, (ii) populations referred to H. errerae var. errerae and H. errerae var. messerii, (iii) a population referred to H. hyblaeum, which, despite morphological and chorological differences, is similar to the other populations of the second group from a genetic stand point. Each population of the above-mentioned taxa has local fragment markers whose frequency is useful to determine how many plants should be sampled in order to collect the seeds necessary to preserve the population's genetic diversity in a genebank.  相似文献   

15.
Hypericum aegypticum subsp. webbii is an evergreen shrub spread in Mediterranean part of central and southeastern Europe. The chemical composition and antimicrobial activity of the essential oil and MeOH extract of H. aegypticum subsp. webbii were investigated. The monoterpenes α‐pinene (63.4 – 68.5%) and β‐pinene (16.9 – 17.0%) were main compounds in the volatile oil from aerial parts. In the cluster analysis, the essential oil of H. aegypticum subsp. webbii was separated and chemically different from the oil of other subspecies of H. aegypticum as well as other Hypericum species from Greece. SIMPER analysis revealed that α‐pinene (24.79%) was the component that contributed the most to differences between all oils. Also, there was extremely high overall dissimilarity between three subspecies of H. aegypticum. MeOH extract of aerial parts of H. aegypticum subsp. webbii contained flavonoids rutin (56.4 ± 0.9 mg/g), hyperoside and quercetin, and phenolic acids chlorogenic and caffeic acid, while naphthodianthrones were not detected. The antimicrobial activity of essential oil was moderate (MIC from 100 to >200 μg/ml), while MeOH extract inhibited the growth of Gram‐positive bacteria Bacillus subtilis, Enterococcus faecalis, Staphylococcus epidermidis, and Micrococcus luteus (MIC 50 – 100 μg/ml), more pronounced than the extract of H. perforatum (MIC 200 – >200 μg/ml).  相似文献   

16.
通过文献、标本研究,结合野外考察及数据统计分析,确认疏花长柄山蚂蝗复合体包括4种1亚种,讨论了各分类群的重要性状,并给出了新的检索表。将湘西长柄山蚂蝗(Hylodesmum laxum subsp.falfolium)处理为原亚种的新异名;订正了《中国植物志》和《Flora of China》等著作中该类群的几个错误的地理分布,记载了我国几个省区的分布新记录,并给出了凭证标本。  相似文献   

17.
The chemical composition of the essential oils of nine taxa from seven sections of Hypericum L. (Guttiferae; H. perforatum subsp. perforatum, H. perforatum subsp. veronense, H. calycinum, H. montanum, H. richeri subsp. richeri, H. hyssopifolium, H. hirsutum, H. hircinum subsp. majus, and H. tetrapterum) occurring in central Italy (Appennino Umbro‐Marchigiano) was analyzed by GC/FID and GC/MS. A total of 186 compounds were identified in the different species and subspecies, accounting for 86.9–92.8% of the total oils. The major fraction of the oil was always represented by sesquiterpene hydrocarbons (30.3–77.2%), while quantitative differences occurred between the other classes of volatiles depending on the taxa considered. Chemical composition of the nine Hypericum entities with respect to the taxonomical classification was discussed. Essential oils obtained from six taxa, i.e., H. perforatum subsp. perforatum, H. perforatum subsp. veronense, H. calycinum, H. richeri subsp. richeri, H. hirsutum and H. tetrapterum, were also tested for their antimicrobial properties against five different microbial strains by the broth‐microdilution method, and they were found to have significant activity (expressed as MIC) on B. subtilis, moderate activity on C. albicans and S. aureus, and weak activity on E. coli and E. faecalis, the most active being those from H. hirsutum, H. richeri subsp. richeri, and H. tetrapterum.  相似文献   

18.
Taxonomic considerations and nomenclatural adjustments as a part of a revision ofLinaria Mill. undertaken within the “Flora iberica” project are presented. Data on morphology, seed coat surface, chorology, ecology, synonymy and variability of 11 accepted taxa are reported. The following new combinations are proposed:Linaria aeruginea subsp. cardonica (Font Quer)L. Sáez etM. Sainz,Linaria depauperata subsp.ilergabona (M.B. Crespo etV.J. Arán)L. Sáez, andLinaria saturejoides subsp.angustealata (Willmott)L. Sáez etM.B. Crespo.  相似文献   

19.
The chemical composition and antioxidant properties of the essential oil and EtOH extract of immortelle (Helichrysum italicum (Roth) G.Don subsp. italicum, Asteraceae) collected in Montenegro were evaluated. The essential oil was characterized by GC/MS analysis, and the content of total phenolics and flavonoids in the EtOH extract was determined using the Folin? Ciocalteu reagent. The free‐radical‐scavenging capacity (RSC) of both the essential oil and the EtOH extract was assessed with the 2,2‐diphenyl‐1‐pycrylhydrazyl (DPPH) method. Moreover, the inhibition of hydroxyl radical (.OH) generation by the EtOH extract of immortelle was evaluated for the first time here. Neryl acetate (28.2%) and γ‐curcumene (18.8%) were the main compounds in the essential oil, followed by neryl propionate (9.1%) and ar‐curcumene (8.3%). The chemical composition of the oils of the examined and additional 16 selected Helichrysum italicum taxa described in literature were compared using principal component (PCA) and cluster (CA) analyses. The results of the statistical analyses implied the occurrence of at least four different main and three subchemotypes of essential oils. Considering the antioxidant properties, the EtOH extract of immortelle exhibited similar potential as propyl gallate and quercetin, while the essential oil exhibited relatively weak DPPH.‐scavenging capacity.  相似文献   

20.
Two small cyprinid fishes, Hemigrammocypris rasborella and Pseudorasbora pumila subsp. (sensu Nakamura 1963), inhabit similar habitats and often occur sympatrically in the Ise Bay basin, central Honshu Island, Japan. Their genetic population structures were revealed, using sequence data from the mitochondrial cytochrome b gene, and then compared. Hemigrammocypris rasborella populations in the Ise Bay area formed a monophyletic group that has been isolated from eastern (Tenryu River) and western (Lake Biwa–Yodo River) populations at least for several hundred thousand years. Pseudorasbora pumila subsp., endemic to the Ise Bay area, was estimated to have become isolated from its sister subspecies, P. p. pumila, about 5 million years ago. Both H. rasborella and P. pumila subsp. had centers of genetic diversity around the Okazaki Plain in the eastern part of the basin and showed trans-bay distribution of haplotypes or haplotype groups. Their common population structure was explained by geological features in the Ise Bay area, in which a large paleo-river system developed in regression periods, suggesting gene flow among populations of each species in the mid to lower reaches of the paleo-river. Based on the estimated expansion or divergence time, however, not all populations experienced gene flow during the Last Glacial. In contrast to the maintenance of high genetic diversity in H. rasborella, almost all populations of P. pumila subsp. have lost mitochondrial DNA genetic diversity. This implies that effective population size of P. pumila subsp. tended to be smaller, probably because of differences in reproductive ecology, even though the two species have been exposed to similar environmental changes. For conservation of the two species, genetic and adaptive differentiation among local populations should be considered, and attention should be paid to inbreeding depression, especially in P. pumila subsp. An erratum to this article can be found at  相似文献   

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