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1.
Polyploid Prunus spinosa (2n = 4×) and P. insititia (2n = 6×) represent enormous genetic potential in Central Europe, which can be exploited in breeding programmes. In Hungary, 17 cultivar candidates were selected from wild-growing populations including 10 P. spinosa, 4 P. insititia and three P. spinosa × P. domestica hybrids (2n = 5×). Their taxonomic classification was based on their phenotypic characteristics. Six simple sequence repeats (SSRs) and the multiallelic S-locus genotyping were used to characterize genetic variability and reliable identification of the tested accessions. A total of 98 SSR alleles were identified, which presents 19.5 average allele number per locus, and each of the 17 genotypes could be discriminated based on unique SSR fingerprints. A total of 23 S-RNase alleles were identified. The complete and partial S-genotype was determined for 8 and 9 accessions, respectively. The identification of a cross-incompatible pair of cultivar candidates and several semi-compatible combinations help maximize fruit set in commercial orchards. Our results indicate that the S-allele pools of wild-growing P. spinosa and P. insititia are overlapping in Hungary. A phylogenetic and principal component analysis confirmed the high level of diversity and genetic differentiation present within the analysed genotypes and helped clarify doubtful taxonomic identities. Our data confirm that S-locus genotyping is suitable for diversity studies in polyploid Prunus species. The analysed accessions represent huge genetic potential that can be exploited in commercial cultivation.  相似文献   

2.
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   

3.
Two new genera, Atractospora and Rubellisphaeria, are described for perithecial ascomycetes occurring on decaying wood submerged in freshwater habitats. Their relationships with other morphologically similar fungi were investigated utilising four nuclear ribosomal and protein-coding loci. They are nested together with members of five orders and families and numerous genera incertae sedis in the Sordariomycetidae in a clade supported by Maximum Likelihood and Bayesian inference methods. Their closest relative is Lentomitella. Atractospora includes species characterised by dark, immersed to semi-immersed beaked ascomata lying horizontally to the host, stipitate asci with a pronounced non-amyloid apical annulus and hyaline, fusiform, septate, thick-walled ascospores with smooth or ornamented wall. Three novel species are introduced (A. decumbens, A. reticulata and A. verruculosa). A new combination for Aquaticola ellipsoidea is proposed in Atractospora based on molecular data and morphological characters. Rubellisphaeria, with a new species R. abscondita, is distinct by subhyaline to reddish brown, immersed ascomata with a lateral neck, short-stipitate asci and ellipsoidal smooth ascospores with a delayed formation of a middle septum. The sexual morph of the dematiaceous hyphomycete genus Myrmecridium was encountered for the first time on decaying wood submerged in a stream. It is nested in a strongly supported monophyletic clade of the Myrmecridiales. The novel species M. montsegurinum is described; it possesses papillate ascomata immersed beneath a clypeus with subhyaline to weakly pigmented ascomatal wall, long-stipitate asci with a non-amyloid apical annulus and three-septate, hyaline, ellipsoidal, delicately verruculose ascospores. A morphology-based key is provided to facilitate identification of species of Atractospora.  相似文献   

4.
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   

5.
Mitochondrial DNA control region of Mus terricolor, three aboriginal species M. spretus, M. macedonicus, M. spicilegus; the Asian lineage M. caroli, M. cervicolor, M. cookii; and the two house mice, M. musculus domesticus and M. m. castaneus were analysed to estimate the substitution rate, phylogenetic relationship and the probable time of divergence. Results showed that M. spretus, M. caroli and M. terricolor are highly diverged from each other (caroli/terricolor = 0.146, caroli/spretus = 0.147 and terricolor/spretus = 0.122), whereas M. spretus showed less divergence with two house mice species (0.070 and 0.071). Sequence divergence between M. terricolor and the Palearctic group were found to be ranging from 0.121 to 0.134. Phylogenetic analysis by minimum evolution, neighbour-joining, unweighed pair group method with arithmetic mean and maximum parsimony showed almost similar topology. Two major clusters were found, one included the Asian lineage, M. caroli, M. cookii and M. cervicolor and the other included the house mice M. m. domesticus, M. m. castaneus and the aboriginal mice M. macedonicus and M. spicilegus along with M. spretus, forming the Palearctic clade. M. terricolor was positioned between the Palearctic and Asian clades. Results showed that Palearctic-terricolor and the Asian lineages diverged 5.47 million years ago (Mya), while M. terricolor had split around 4.63 Mya from their ancestor. M. cervicolor, M. cookii and M. caroli diverged between 4.70 and 3.36 Mya, which indicates that M. terricolor and the Asian lineages evolved simultaneously. M. spretus is expected to have diverged nearly 2.9 Mya from their most recent common ancestor.  相似文献   

6.
Traditionally viewed as an Andean grain crop,Chenopodium quinoa Willd. includes domesticated populations that are not Andean, and Andean populations that are not domesticated. Comparative analysis of leaf morphology and allozyme frequencies have demonstrated that Andean populations, both domesticated(quinua) and free-living(ajara), represent an exceptionally homogeneous unit that is well differentiated from allied domesticates of coastal Chile(quingua) and freeliving populations of the Argentine lowlands(C. hircinum). This pattern of relationships indicates that Andean populations represent a monophyletic crop/weed system that has possibly developed through cyclic differentiation (natural vs. human selection) and introgressive hybridization. Relative levels of variation suggest that this complex originated in the southern Andes, possibly from wild types allied withC. hircinum, with subsequent dispersal north to Colombia and south to the Chilean coast. Coastal populations were apparently isolated from post-dispersal differentiation and homogenization that occurred in the Andes. Other data point toward a center of origin in the northern Andes with secondary centers of genetic diversity subsequently developing in the southern Andes and the plains of Argentina. Comparative linkage of South American taxa, all tetraploid, with North American tetraploids of the subsection will eventually clarify this problem. While the possibility of a direct phyletic connection betweenC. quinoa and the Mexican domesticate(C. berlandieri subsp. nuttalliae,) cannot be excluded, available evidence indicates that the latter represents an autonomous lineage that is associated with the basal tetraploid, C. b. subsp.berlandieri, through var.sinuatum, whereas South American taxa show possible affinities to either var. zschackei or var.berlandieri. An extinct domesticate of eastern North America,C. b. subsp.jonesianum, represents either another instance of independent domestication, possibly from subsp. b. var.zschackei, or a northeastern outlier of subsp.nuttalliae.  相似文献   

7.
A revision of Penstemon sect. Saccanthera subsect. Serrulati includes a new species (P. salmonensis), a new variety (P. triphyllus var. infernalis), and the elevation of a subspecies to species (P. curtiflorus), bringing the total number of species to eight, which are keyed and described, complete with nomenclature and type citations.  相似文献   

8.
9.
Phylogenetic analyses based on protein-encoding gene exons and introns of ATP citrate lyase (ACL1), beta tubulin (TUB), the largest subunit of RNA polymerase II (RPB1), and translation elongation factor 1-α (TEF1) are used for inferring the existence of a new Clonostachys species from the Cerrado biome in Brazil, described here as C. chloroleuca. The species produces dimorphic, primary, and secondary conidiophores that form consistently greenish conidial masses on artificial media. It resembles therefore C. rosea f. catenulata although it differs from this species by less adpressed branches in the secondary conidiophores. The new species is also phylogenetically related to C. byssicola and C. rhizophaga. Our inventory suggests that C. byssicola, C. chloroleuca, C. pseudochroleuca, C. rhizophaga, C. rogersoniana, and C. rosea commonly occur in native and agriculturally used soils of the Cerrado and Amazon Forest. Using sequences available from two genome-sequenced strains employed as biological control agents, we confirm the identity of the European strain IK726 as C. rosea and identify strain 67-1 from China as C. chloroleuca.  相似文献   

10.
In this contribution on the genus Cantharellus in Asia, C. subvaginatus is described from the Republic of Korea as a close relative to the Chinese C. vaginatus, which is here reported for the first time from India. Both species are here placed in Cantharellus subg. Cantharellus sect. Amethystini, together with the Indian C. pseudoformosus (syn.: C. umbonatus) and the Malayan C. subamethysteus. As such, Asia has suddenly become the continent with the highest diversity for Amethystini. Species delimitation in sect. Amethystini is molecularly supported by a combined phylogenetic analysis of rDNA sequences obtained for LSU and ITS and additionally suggests the existence of a still undescribed species in North America. Character variability is discussed for all known members of Amethystini, including atypical specimens of the North American C. lewisii that are morphologically more reminiscent of the South Korean C. subvaginatus.  相似文献   

11.
Semi-sessile Mytilus mussels are used as indicators of climate changes, but their geographic distribution is not sufficiently known in the Arctic. The aim of this study was to investigate the taxonomic status and genetic differentiation of Mytilus populations in a Northwest Greenlandic fjord at Maarmorilik, impacted by contaminations from a former mine. In this study, mussels were collected at three sites differing in exposure to environmental factors. A total of 54 polymorphic SNPs found in the Mytilus EST and DNA sequences analyzed were successfully applied to 256 individuals. The results provided the first evidence for the existence of M. trossulus in Greenland. The mussel from M. trossulus and M. edulis taxa are shown to coexist and hybridize in the fjord. The three studied sites were found to differ significantly in the distribution of taxa with a higher prevalence of M. trossulus in the inner fjord. The identified M. edulis × M. trossulus hybrids mostly had a hybrid index score of about 0.5, indicating a similar number of alleles characteristic for M. trossulus and M. edulis. There was a low number of backcrosses between ‘pure’ taxa and hybrids. This newly discovered hybrid zone between the two taxa is unique in comparison with the Canadian populations. As Mytilus mussels in Greenland hitherto have been regarded as the one taxon M. edulis, the results have importance for biogeography and future monitoring and environmental studies.  相似文献   

12.
2C DNA content and ploidy level variation of Prunus spinosa and closely related taxa together with Prunus domestica L. and Prunus insititia L. was studied in Slovakia. The aim of the study was to define genome sizes and find differences between closely related taxa within Prunus spinosa sensu lato mentioned in previous works. According to our results, investigated taxa can be divided into three groups according to ploidy level: Prunus spinosa, Prunus dasyphylla, Prunus ×fruticans, Prunus ×dominii and Prunus ×schurii are tetraploids, Prunus ×fechtneri is pentaploid, and P. domestica and P. insititia are hexaploids. Genome size differences within tetraploid taxa were relatively small (Prunus spinosa: 1.40?±?0.02, P. ×domini: 1.44?±?0.01, P. ×fruticans: 1.48?±?0.02, P. ×schurii: 1.44?±?0.02), but statistically significant. Although further research is needed, it seems that the concept of several taxa as product of hybridization between P. spinosa and cultivated plum species has been supported by our study.  相似文献   

13.
14.
Two new species of Metarhizium, M. bibionidarum and M. purpureogenum are described from Japan. Metarhizium bibionidarum is the phylogenetic sister species of M. pemphigi and a member of the M. flavoviride species complex. It is distinguished morphologically from M. pemphigi by its larger conidia. The species is based on a collection of an infected March fly larva (Diptera: Bibionidae) but is also known to occur on fruit beetle (Coleoptera: Scarabaeidae) encountered in France. Metarhizium purpureogenum was isolated from soil by plating and insect baiting methods and represents a unique phylogenetic lineage placed outside the M. anisopliae and M. flavoviride species complexes. Three isolates of M. purpureogenum excreted a distinctive red-purple pigment into agar medium when co-cultured with M. robertsii or Aspergillus oryzae.  相似文献   

15.
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   

16.
17.
Pathogenicity of Candida albicans is associated with its capacity switch from yeast-like to hyphal growth. The hyphal form is capable to penetrate the epithelial surfaces and to damage the host tissues. Therefore, many investigations have focused on mechanisms that control the morphological transitions of C. albicans. Recently, certain studies have showed that non-albicans Candida species can reduce the capacity of C. albicans to form biofilms and to develop candidiasis in animal models. Then, the objective of this study was to evaluate the effects of Candida krusei and Candida glabrata on the morphogenesis of C. albicans. Firstly, the capacity of reference and clinical strains of C. albicans in forming hyphae was tested in vitro. After that, the expression of HWP1 (hyphal wall protein 1) gene was determined by quantitative real-time PCR (polymerase chain reaction) assay. For both reference and clinical strains, a significant inhibition of the hyphae formation was observed when C. albicans was incubated in the presence of C. krusei or C. glabrata compared to the control group composed only by C. albicans. In addition, the culture mixed of C. albicans-C. krusei or C. albicans-C. glabrata reduced significantly the expression of HWP1 gene of C. albicans in relation to single cultures of this specie. In both filamentation and gene expression assays, C. krusei showed the higher inhibitory activity on the morphogenesis of C. albicans compared to C. glabrata. C. krusei and C. glabrata are capable to reduce the filamentation of C. albicans and consequently decrease the expression of the HWP1 gene.  相似文献   

18.
Here we evaluate the origins and relationships of Mexican and Central American Diplazium hybrids derived from crosses involving either D. plantaginifolium or D. ternatum. Based on study of live plants and herbarium specimens, we distinguish D. ×verapax from the similar D. riedelianum and present evidence that the former is a sterile hybrid derived from a cross between D. plantaginifolium and D. werckleanum. We also describe new hybrids, D. ×torresianum and D. ×subternatum from Mexico and northern Central America. Both involve D. ternatum as one parent. Diplazium. cristatum is the other putative parent of D. ×torresianum, and D. plantaginifolium is the second parent of D. ×subternatum. We also designate lectotypes for D. cordovense and D. dissimile.  相似文献   

19.
20.
Molecular markers derived from the complete chloroplast genome can provide effective tools for species identification and phylogenetic resolution. Complete chloroplast (cp) genome sequences of Capsicum species have been reported. We herein report the complete chloroplast genome sequence of Capsicum baccatum var. baccatum, a wild Capsicum species. The total length of the chloroplast genome is 157,145 bp with 37.7 % overall GC content. One pair of inverted repeats, 25,910 bp in length, was separated by a small single-copy region (17,974 bp) and large single-copy region (87,351 bp). This region contains 86 protein-coding genes, 30 tRNA genes, 4 rRNA genes, and 11 genes contain one or two introns. Pair-wise alignments of chloroplast genome were performed for genome-wide comparison. Analysis revealed a total of 134 simple sequence repeat (SSR) motifs and 282 insertions or deletions variants in the C. baccatum var. baccatum cp genome. The types and abundances of repeat units in Capsicum species were relatively conserved, and these loci could be used in future studies to investigate and conserve the genetic diversity of the Capsicum species.  相似文献   

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