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1.
The genus Scutellaria (Lamiaceae, Scutellarioidae) includes taxa with a wide range of pharmacological traits, which make this genus economically important. Previous taxonomical studies on Scutellaria were mainly based on morphological and chromosomal characters. The infrageneric classification of the genus has been the subject of a long controversy among authors, and delimitation of taxa remains problematic. In this study, the phylogeny of the genus was evaluated using nrDNA ITS and trnL-F sequences, with a focus on the 42 Iranian taxa belonging to subgenera Apeltanthus and Scutellaria. In both ITS and trnL-F trees, there were two main clades within the genus corresponding to the two subgenera Scutellaria and Apeltanthus. In the subg. Scutellaria, the sect. Anaspis was monophyletic, but the monophyly of sect. Scutellaria was not supported. In this subgenus, S. galericulata was located away from other species in both trees, supported the isolation of this species from the sect. Scutellaria and inclusion in the sect. Galericularia as was previously considered by some authors. In subg. Apeltanthus, sect. Apeltanthus and sect. Lupulinaria were not monophyletic; furthermore, the monophyly of subsect. Lupulinaria was not supported. Based on the results of this study, it can be suggested that the sectional classification of both subgenera Apeltanthus and Scutellaria should be revised.  相似文献   

2.
Phylogenetic relationships among the six Iris subgenera were reconstructed by chloroplast trnL-F sequences data using maximum likelihood. The entire matrix of aligned bases analyzed includes 1043 characters and the length of all sequences varied from 747 bp to 893 bp, and mutation sites accounted for 18.79% of the total length. The cluster analysis results accorded well with the subgeneric classification of Chinese Iris species. Results suggested rhizomes and sepals lacking ornament are ancestral characters, and subg. Xyridion and subg. Limniris are more primordial than another four subgenera. Subgenus Nepalensis and subg. Xyridion were resolved as monophyletic.  相似文献   

3.
Polyploidization has long been recognized as one of the most important driving forces of plant evolution. Aconitum subgenus Lycoctonum (Ranunculaceae) has a wide distribution range and well-known background of polyploidy, thereby providing a potentially valuable model to explore polyploid origin and evolutionary history. However, the phylogeny of subg. Lycoctonum has not yet been completely resolved. In the current study, 29 species including diploid, tetraploid and hexaploid species were sampled in subg. Lycoctonum. Using four cpDNA regions (ndhF-trnL, psbA-trnH, psbD-trnT and trnT-L) and two nrDNA regions (internal transcribed spacer, ITS, and external transcribed spacer, ETS), phylogenetic relationship was first reconstructed for the polyploid species within subg. Lycoctonum. In combination with nuclear diversification rate estimation, cpDNA haplotype network, ancestral area reconstruction as well as morphological and karyotypic evidence, potential origin and divergence time were further assessed among the polyploid species. Hybridization was inferred for A. angustius and A. finetianum was suggested to be the potential maternal progenitor, due to their close phylogenetic relationship, highly similar morphologies and overlapping distribution range. Local origin was inferred for tetraploids in the Hengduan Mountains (HDM) with eight groups of chromosomes of four homeologous, which diverged approximately 3.00 Ma in the same period of the orogeny of the HDM. The hexaploid A. apetalum was inferred to suffer from geographical isolation due to the formation of the Qinghai–Tibetan Plateau (QTP) and the HDM. Hybridization and heterogeneous habitats in the HDM were suggested to play an important role in the polyploidization in subg. Lycoctonum.  相似文献   

4.
The hybrid origin of Miscanthus purpurascens has previously been proposed, primarily because of its intermediate morphology. In this study, phylogenies based on the DNA sequences from the internal transcribed spacer region of nuclear ribosomal DNA (nrDNA ITS), on the DNA sequences of the trnL intron and trnL-F intergenic spacer of chloroplast DNA, and on amplified fragment length polymorphism (AFLP) fingerprinting confirm that M. purpurascens originated through homoploid hybridization between M. sinensis and M. sacchariflorus. Two different types of ITS sequences were identified from almost all plants of M. purpurascens. One type was found to be closely related to M. sinensis and the other to M. sacchariflorus. Miscanthus purpurascens was found to possess many M. sinensis- and M. sacchariflorus-specific AFLP bands but no band specific to itself. Clustering with the Unweighted Pair Group Method with Arithmetic Mean and principal coordinate analysis based on the AFLP data also demonstrated that M. purpurascens is an approximate intermediate of the two species. In addition, M. purpurascens has the plastid genome of M. sinensis or M. sacchariflorus, suggesting that either species could be its maternal parent. All specimens of M. purpurascens and its coexisting parental species are identified as diploids (2n = 2x = 38). Possible mechanisms of natural hybridization, hybrid status, chloroplast DNA recombination, and evolutionary implications of this hybridization are also discussed.  相似文献   

5.
Salvia subg. Calosphace (Lamiaceae, Lamiales) is a highly diverse clade endemic to the New World. The phylogenetic relationships of Calosphace have been previously investigated using DNA sequences of nuclear ITS region and plastid psbA–trnH intergenic spacer, but the resulting trees lack resolution and support for many clades. The present paper reassesses the phylogenetic relationships of subgenus Calosphace, including a broader taxon sampling, with a special focus on representing previously unsampled sections, and using an additional plastid marker (trnL–trnF region). Our results show increased resolution and overall patterns of support, recovering ten main clades. Within core Calosphace, the most inclusive of these main clades, 17 new subclades were identified. Of the 42 sections for which more than one species was analysed, only 12 are monophyletic. Our biogeographical analysis identified at least twelve migrations to South America from Mexican and Central American lineages, in agreement with previous suggestions of multiple origins of South American Calosphace diversity. This analysis also confirmed a colonization of the Antilles by Andean lineages. The reconstruction of ancestral states of pollination syndromes showed multiple shifts to ornithophily from melittophily and one reversal to the latter.  相似文献   

6.
7.
Ulleung Island is an oceanic volcanic island in Korea, which has never been connected to the adjacent continent. Previous studies highlighted Ulleung Island as an excellent system to study the pattern and process of early stages of flowering plant evolutions on oceanic island. The predominant mode of speciation in flowering plants on Ulleung Island appears to be anagenesis. However, the potentially important role of hybrid speciation among incompletely reproductively isolated lineages cannot be ruled out. Viola woosanensis (Violaceae) is of purportedly hybrid origin between V. ulleungdoensis (i.e., formerly recognized as V. selkirkii in Ulleung Island) and V. chaerophylloides, based on morphology. To examine the origin of V. woosanensis, we sampled a total of 80 accessions, including V. woosanensis and its putative parental species and sequenced nrDNA ITS, and four highly variable chloroplast noncoding regions (trnL-trnF, rpl16 intron, atpF-atpH, and psbA-trnH). Representative species of Viola from Korea were also included in the phylogenetic analyses (maximum parsimony, maximum likelihood, and Bayesian inference). Additive polymorphic sites in the nrDNA ITS regions were confirmed by cloning amplicons from representative species. The molecular data strongly supported the hybrid origin of V. woosanensis, and the maternal and paternal parent were determined to be V. ulleungdoensis and V. chaerophylloides, respectively. The presence of two parental ribotypes in V. woosanensis (with the exception in one population) was confirmed by cloning, suggesting V. woosanensis is primarily the F1 generation. No trace of backcrossing and introgression with its parents was detected due to low fertility of hybrid species. We found a multiple and unidirectional hybrid origin of V. woosanensis. Additional studies are required to determine which factors contribute to asymmetric gene flow of Viola species in Ulleung Island.  相似文献   

8.
Hybridization between alien and native species is biologically very important and could lead to genetic erosion of native taxa. Solidago × niederederi was discovered over a century ago in Austria and described by Khek as a natural hybrid between the alien (nowadays regarded also as invasive) S. canadensis and native S. virgaurea. Although interspecific hybridization in the genus Solidago is considered to be relatively common, hybrid nature of S. × niederederi has not been independently proven using molecular tools, to date. Because proper identification of the parentage for the hybrid Solidago individuals solely based on morphological features can be misleading, in this paper we report an additive polymorphism pattern expressed in the ITS sequences obtained from individuals representing S. × niederederi, and confirm the previous hypothesis that the parental species of this hybrid are S. canadensis and S. virgaurea. Additionally, based on variability at the cpDNA rpl32-trnL locus, we showed that in natural populations hybridization occurs in both directions.  相似文献   

9.
Little is known about the arbuscular mycorrhizal status of the ligneous plant Jatropha curcas, an energy crop that raises high expectations worldwide. We hypothesized that its early mycorrhization and growth could be improved by co-culturing it with Crotalaria retusa, a mycotrophic legume species. Soil samples collected from a 15-year-old J. curcas hedgerow were transferred to the greenhouse, along with soil sampled from the contiguous fallow field. Three pot-culture modalities were studied for 3 months: jatropha alone, jatropha sowed after the clipping of 2-month-old C. retusa, and jatropha sowed next to 2-month-old C. retusa. J. curcas biomass was significantly lower when it was co-cultured with C. retusa in both soil types as compared to when it was grown individually, while its biomass following the cut of C. retusa was not impacted. J. curcas shoot P content was significantly improved only when both plant species grew in the hedgerow soil, and so was mycorrhization intensity. Additionally, the composition of the J. curcas root mycorrhizal community was closer to that of C. retusa when using this hedgerow soil. Overall, J. curcas development was not improved by its association with C. retusa, but the soil cropping history appeared essential to their mycorrhizal interactions. These were favored by a soil mycorrhizal community shaped by multiple years of J. curcas monoculture. Improved knowledge about these preferential association patterns with J. curcas is needed to improve its co-culture with compatible mycotrophic legumes.  相似文献   

10.
Molecular phylogenetic tools are often useful in distinguishing cryptic species with similar morphologies, but they can also be helpful in identifying morphotypes of a species, which displays completely different shapes. We performed molecular-phylogenetic analysis of supra-tidal green algae in the Kamchatka peninsula that belong to the order Prasiolales (Trebouxiophyceae, Chlorophyta). Based on rbcL sequences results, two new species were recorded for the first time in Kamchatka. Approximately 1.4% of the field-collected Rosenvingiella constricta had a unique uniseriate hood-like blade shape, although their rbcL sequences were 100% identical with typical multiseriate filamentous plants. Kamchatka’s population of R. constricta showed 99.4–99.6% identity in rbcL sequences with the populations from Canada and New Zealand. Another similar-looking Rosenvingiella species collected from the same locality had 93.5% identity of the rbcL gene sequence with R. constricta. Morphological and geographical analyses also suggested that this species might be a new species of the genus Rosenvingiella. Prasiola delicata was recorded for the first time in Kamchatka. The Kamchatka population of P. delicata showed 100% identity in rbcL gene sequence with the population from Vancouver, but differed from the Canadian population morphologically.  相似文献   

11.
12.
It is rather difficult to construct a system of gray voles of the tribe Microtini by a set of morphological and karyological characters because form generation is mosaic at these organization levels. The sequence of the mitochondrial cytochrome b gene was used to study the phylogenetic relationships and taxonomic position of the Central Asian subgenus Blanfordimys. Afghan vole Microtus (Blanfordimys) afghanus and Bucharian vole M. (Blanfordimys) bucharensis clustered with Pamir vole M. (Neodon) juldaschi, which is conventionally assigned to another subgenus. The last two species proved to be significantly closer to each other than either of them was to M. (Blanfordimys) afghanus, which disagrees with the monophyletic origin accepted for Blanfordimys. The genetic distances between the species of the subgenus Blanfordmys and M. juldaschi were comparable with the distances between the sister subgenera Microtus s. str. and Sumeriomys or Pallasiinus and Alexandromys and with the basal divergence of supraspecific clades in the subgenus Terricola. It was assumed that a special Central Asian group of species exists within the tribe Microtini and includes species of the subgenus Blanfordimys and M. juldaschi and that the subgenera Neodon and Blanfordimys should be revised.  相似文献   

13.
Based upon DNA sequences from six plastid regions (rbcL, psbB-psbH, trnL-trnF, rpS16, psbA-trnH, rpS16-trnK) and the internal transcribed spacer (ITS) region of nuclear ribosomal DNA, the phylogenetic relationships in the genus Nitraria and family Nitrariaceae are investigated by using methods of maximum parsimony, maximum likelihood, and Bayesian inference. Our study strongly supports the monophyly of Nitraria. Nitraria can be divided into four parts, namely, the N. sphaerocarpa group, N. retusa group, the N. roborowskii and N. tangutorum group, and a group consisting of N. schoberi, N. komarovii, N. sibirica, and N. billardieri. Ancestral area reconstruction using S-Diva shows that eastern Central Asia is most likely the place of origin, and then dispersals occurred to western Central Asia, Africa, and Australia.  相似文献   

14.
The phylogenetic relationships and phylogeography of two relatively rare Macaronesian Lactuca species, Lactuca watsoniana (Azores) and L. palmensis (Canary Islands), were, until this date, unclear. Karyological information of the Azorean species was also unknown. For this study, a chromosome count was performed and L. watsoniana showed 2n = 34. A phylogenetic approach was used to clarify the relationships of the Azorean endemic L. watsoniana and the La Palma endemic L. palmensis within the subtribe Lactucinae. Maximum parsimony, Maximum likelihood and Bayesian analysis of a combined molecular dataset (ITS and four chloroplast DNA regions) and molecular clock analyses were performed with the Macaronesian Lactuca species, as well as a TCS haplotype network. The analyses revealed that L. watsoniana and L. palmensis belong to different subclades of the Lactuca clade. Lactuca watsoniana showed a strongly supported phylogenetic relationship with North American species, while L. palmensis was closely related to L. tenerrima and L. inermis, from Europe and Africa. Lactuca watsoniana showed four single-island haplotypes. A divergence time estimation of the Macaronesian lineages was used to examine island colonization pathways. Results obtained with BEAST suggest a divergence of L. palmensis and L. watsoniana clades c. 11 million years ago, L. watsoniana diverged from its North American sister species c. 3.8 million years ago and L. palmensis diverged from its sister L. tenerrima, c. 1.3 million years ago, probably originating from an African ancestral lineage which colonized the Canary Islands. Divergence analyses with *BEAST indicate a more recent divergence of the L. watsoniana crown, c. 0.9 million years ago. In the Azores colonization, in a stepping stone, east-to-west dispersal pattern, associated with geological events might explain the current distribution range of L. watsoniana.  相似文献   

15.
Jatropha curcas and Jatropha mollissima plants were evaluated under conditions of high (HSM) and low (LSM) soil moisture in a semi-arid environment, as changes in the content and concentration of epicuticular wax and the leaf metabolism which could have a relationship with drought tolerance. Besides epicuticular wax, gas exchange, antioxidant system and biochemical parameters of the photosynthetic metabolism were measured. The epicuticular wax content increased only in J. mollissima leaves 95 % under LSM, when compared with HSM conditions. Therefore, J. curcas invested less in the production of long-chain n-alkanes than did J. mollissima under LSM conditions. J. mollissima plants showed the highest CO2 assimilation rate during the HSM period compared to J. curcas. Both species showed high stability in some leaf biochemistry products, highlighting the highest sugar content, free amino acids, total soluble protein, and photosynthetic pigments in the leaves of J. mollissima plants under both of the soil moisture conditions. Moreover, the stability and performance of the different parameters, such as morphologic variables, seem to allow J. mollissima plants to tolerate semi-arid conditions.  相似文献   

16.
17.
During the spring and summer of 2014 and 2015, wheat and barley fields in the Iranian provinces of Golestan and Alborz showed a high incidence of symptoms of black (sooty) head mold of wheat and barley. The isolation results revealed that Alternaria was associated with these symptoms. One hundred and forty isolates were collected and morphologically characterized based on the development of conidial chains with primary, secondary, and tertiary branching patterns, consistent with the three-dimensional sporulation complexity of members of Alternaria in sections Infectoriae and Pseudoalternaria. Subsequently, 16 Alternaria isolates exhibiting high morphological diversity were characterized based on extensive morphological and molecular comparisons. Phylogenetic analyses of three loci [ITS, glyceraldehyde 3-phosphate dehydrogenase (gpd), and plasma membrane ATPase (ATPase)] revealed that 15 isolates belonged to section Infectoriae but could not be assigned to phylogenetic species and one isolate represents a new species, Alternaria kordkuyana sp. nov., in section Pseudoalternaria. Morphological assessments revealed a high degree of variation among section Infectoriae isolates and that A. kordkuyana has significant morphological differences as compared to the three other species currently described in section Pseudoalternaria.  相似文献   

18.
SnRK2s are a large family of plant-specific protein kinases, which play important roles in multiple abiotic stress responses in various plant species. But the family in Gossypium has not been well studied. Here, we identified 13, 10, and 13 members of the SnRK2 family from Gossypium raimondii, Gossypium arboreum, and Gossypium hirsutum, respectively, and analyzed the locations of SnRK2 homologs in chromosomes based on genome data of cotton species. Phylogenetic tree analysis of SnRK2 proteins showed that these families were classified into three groups. All SnRK2 genes were comprised of nine exons and eight introns, and the exon distributions and the intron phase of homolog genes among different cotton species were analogous. Moreover, GhSnRK2.6 was overexpressed in Arabidopsis and upland cotton, respectively. Under salt treatment, overexpressed Arabidopsis could maintain higher biomass accumulation than wild-type plants, and GhSnRK2.6 overexpression in cotton exhibited higher germination rate than the control. So, the gene GhSnRK2.6 could be utilized in cotton breeding for salt tolerance.  相似文献   

19.
20.
Phylogeographic patterns of Ammopiptanthus in northwestern China were examined with internal transcribed spacer (ITS) and three chloroplast intergenic spacers (trnH–psbA, trnL–trnF, and trnS–trnG). Two ITS genotypes (a–b) and 8 chloroplast haplotypes (A–H) were detected. Both ITS genotypes and chloroplast lineages were split in two geographic regions: western Xinjiang and the Alxa Desert. This lineage split was also supported by AMOVA analysis and the Mantel test. AMOVA showed that 89.81 % of variance in Ammopiptanthus occurred between the two geographic regions, and correlation between genetic distances and geographical distances was significant (r = 0.757, p < 0.0001). All populations in western Xinjiang shared haplotype A with high frequency, and range expansion was strongly supported by negative Fu’s FS value, and mismatch distribution analysis, whereas populations in the Alxa Desert had higher genetic diversity and structure. We speculate that the cold and dry climate during the early Quaternary fragmented habitats of the species, limiting gene flow between regions, and interglacial periods most likely led to the range expansion in western Xinjiang. The low genetic diversity of Ammopiptanthus indicate a significant extinction risk, and protective measures should be taken immediately.  相似文献   

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