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Peach belongs to the genus Prunus, which includes Prunus persica and its relative species, P. mira, P. davidiana, P. kansuensis, and P. ferganensis. Of these, P. ferganensis have been classified as a species, subspecies, or geographical population of P. persica. To explore the genetic difference between P. ferganensis and P. persica, high-throughput sequencing was used in different peach accessions belonging to different species. First, low-depth sequencing data of peach accessions belonging to four categories revealed that similarity between P. ferganensis and P. persica was similar to that between P. persica accessions from different geographical populations. Then, to further detect the genomic variation in P. ferganensis, the P. ferganensis accession “Xinjiang Pan Tao 1” and the P. persica accession “Xia Miao 1” were sequenced with high depth, and sequence reads were assembled. The results showed that the collinearity of “Xinjiang Pan Tao 1” with the reference genome “Lovell” was higher than that of “Xia Miao 1” and “Lovell” peach. Additionally, the number of genetic variants, including single nucleotide polymorphisms (SNPs), structural variations (SVs), and the specific genes annotated from unmapped sequence in “Xia Miao 1” was higher than that in “Xinjiang Pan Tao 1” peach. The data showed that there was a close distance between “Xinjiang Pan Tao 1” (P. ferganensis) and reference genome which belong to P. persica, comparing “Xia Miao 1” (P. persica) and reference ones. The results accompany with phylogenetic tree and structure analysis confirmed that P. ferganensis should be considered as a geographic population of P. persica rather than a subspecies or a distinct species. Furthermore, gene ontology analysis was performed using the gene comprising large-effect variation to understand the phenotypic difference between two accessions. The result revealed that the pathways of gene function affected by SVs but SNPs and insertion-deletions markedly differed between the two peach accessions.  相似文献   

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The structure and seasonal dynamics of marine algal communities dominated by Cystoseira crinita Duby, 1830 were studied in the northeastern Black Sea at depths of 2, 5, and 10 m. Seasonal fluctuations were found to be mainly manifested in biomass changes of the dominant species C. crinita at depths of 2 and 5 m. No seasonal changes in the studied parameters of communities were found at a depth of 10 m. The mean annual production of C. crinita was 1472.3 g/m2, with the maximum at a depth of 5 m (2148.1 g/m2). The minimum production was observed at a depth of 10 m. At all depths, the production of C. crinita was highest in the spring; this index had zero values in the fall and winter.  相似文献   

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The extremely high diversity of spined loach biotypes in the Lower Danube has been detected by biochemical genetic investigation and cytometric analysis of 358 specimens collected in the riverbed and shallow channels. Along with two diploid species (C. elongatoides and C. “tanaitica”), six hybrid forms were revealed, namely, diploid C. elongatoides-“tanaitica”; triploid C. 2 elongatoides-“tanaitica,” C. elongatoides-2 “tanaitica,” and C. 2 elongatoides-species-1; and tetraploid C. 3 elongatoides-“tanaitica” and C. elongatoides-species-2-2 “tanaitica.” In addition, specimens with recombinant genotypes were also found. In spite of the apomictic mode of reproduction, the polyploids did not possess clonal structure, but according to the level of polymorphism and the genotype distribution, they were isomorphous to parental diploid species. Thus, in contrast to the polyploidy in Cobitids of the Dnieper, which have appeared in the basin due to the expansion, the polyploids of the Lower Danube are autochthonous and were derived by crossing with local diploid species. The process is apparently proceeds without any limitations.  相似文献   

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Comparative sequence analysis of symbiotic genes (nodA, nodC, nodD, nifH), which are elements of accessory component of the rhizobial genome, demonstrated that the strains of Rhizobium leguminosarum bv. viciae, isolated from the nodules of a relic legume, Vavilovia formosa, the closest relative of hypothetical common ancestor of the tribe Fabeae, represented a group separated from the strains of R. leguminosarum bv. viciae, isolated from other representatives of this tribe (Vicia, Lathyrus, Pisum, Lens). No isolation was observed relative to the genes representing the core component of the rhizobial genome (16S rDNA, ITS, glnII) or relative to host specificity of the rhizobia. The data obtained suggest that sequence divergence of symbiotic genes marks the initial stage of sympatric speciation, which can be classified as the isolation of the relic “vaviloviae” symbiotype, a possible evolutionary precursor of the “viciae” biotype.  相似文献   

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The Espinhaço Range, in eastern Brazil, has a peculiar landscape that has influenced the vegetation pattern of the region because of its valleys, canyons, ranges and disjunct rock outcrops found at high elevations. In this region, the vegetation type known as campos rupestres (rupestrian fields), which occurs in the disjunct outcrops, has high levels of species richness and endemism. Vellozia gigantea, a 6-m tall dracenoid monocot, is a vulnerable species endemic to this vegetation and has a narrow distribution that extends approximately 27 km. This region is located in a disturbed area, where populations are divided into three geographical groups, separated by a canyon and a valley. For this study, we used ISSR markers to measure the genetic diversity of the species and test the hypothesis that the canyon and the valley constitute geographical barriers to gene flow in V. gigantea. Nine populations and 173 individuals were analyzed using nine ISSR primers, which produced 89 fragments. In spite of being a vulnerable species with a narrow distribution, the populations of V. gigantea have high genetic diversity (mean percentage of polymorphic loci = 56.6%; mean Shannon’s index of diversity = 0.278; mean expected heterozygosity = 0.183). Genetic divergence among populations was high (ΦST = 0.28), and principal coordinate, neighborjoining and Bayesian analyses showed that only the canyon may constitute a partial barrier to gene flow in this species. Groups of populations separated by the canyon should be managed separately because they contain different gene pools.  相似文献   

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A preliminary account of Hypoxylon species (Xylariaceae) from the hitherto widely unexplored “Yungas” mountain forests of Northwest Argentina is presented. Two new species are described based on extensive morphological, molecular (ITS region of rDNA, partial β-tubulin gene) and chemotaxonomic data. Hypoxylon spegazzinianum is close to H. erythrostroma, but differs by larger ascospores and a virgariella-like asexual morph. Hypoxylon calileguense resembles H. subgilvum when growing on wood, but can be distinguished by larger ascospores and a fawn to brick stromatal surface colour. Stromata found on bark have affinities to H. pelliculosum, but differ in their stromatal surface colour and conspicuous amyloid apical apparatus. In addition, nine taxa of Hypoxylon are reported for Argentina for the first time, and some details on their asexual state and stromatal secondary metabolites are reported. An updated dichotomous key for Hypoxylon species from Argentina is provided.  相似文献   

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Here, we report for the first time the genome-wide identification and expression analysis of the molecular chaperone BiP genes in Citrus. Six genes encoding the conserved protein domain family GPR78/BiP/KAR2 were identified in the genome of Citrus sinensis and C. clementina. Two of them, named here as CsBiP1 and CsBiP2, were classified as true BiPs based on their deduced amino acid sequences. Alignment of the deduced amino acid sequences of CsBiP1 and CsBiP2 with BiP homologs from soybean and Arabidopsis showed that they contain all the conserved functional motifs of BiPs. Analysis of the promoter region of CsBiPs revealed the existence of cis-acting regulatory sequences involved in abiotic, heat-shock, and endoplasmic reticulum (ER) stress responses. Publicly available RNA-seq data indicated that CsBiP1 is abundantly expressed in leaf, flower, fruit, and callus, whereas CsBiP2 expression is rarely detected in any tissues under normal conditions. Comparative quantitative real-time PCR (qPCR) analysis of expression of these genes between C. sinensis grafted on the drought-tolerant “Rangpur” lime (C. limonia) and -sensitive “Flying Dragon” trifoliate orange (Poncirus trifoliata) rootstocks showed that CsBiP1 was upregulated by drought stress on the former but downregulated on the latter, whereas the CsBiP2 mRNA levels were downregulated on drought-stressed “Flying Dragon,” but remained constant on “Rangpur.” CsBiP2 upregulation was only observed in C. sinensis seedlings subjected to osmotic and cold treatments. Taken together, these results indicate the existence of two highly conserved BiP genes in Citrus that are differentially regulated in the different tissues and in response to abiotic stresses.  相似文献   

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DNA sequences of Capitotricha bicolor from Quercus, Fagus sylvatica, Alnus alnobetula, and Nothofagus, and C. rubi from Rubus idaeus were obtained from apothecia to establish whether specimens from different hosts belong to separate species. The obtained ITS1–5.8S–ITS2 rDNA sequences were examined with Bayesian and parsimony phylogenetic analyses. Intra- and interspecific variation was also investigated based on molecular distances in the ITS region. The phylogenetic analyses supported the specific distinctness of Capitotricha rubi and the Capitotricha from Nothofagus, but also suggest specific distinctness between samples from Quercus, Fagus, and Alnus. The interspecific distances were larger than intraspecific distances for all examined units. The smallest distance was found between the “Alnus alnobetula” and “Fagus sylvatica” units. Two new sequences of Brunnipila are published. Capitotricha, Lachnum, and Erioscyphella are compared to each other based on hair and excipulum characteristics.  相似文献   

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A new Dienia type of the embryogenesis of orchid plants differing from the Liparis type, earlier observed for the tribe Malaxideae, has been described in Dienia ophrydis (J. Köenig) Seidenf. (Orchidaceae). The Dienia-type embryogenesis is characterized by the following features: (1) development of a single-celled suspensor formed by a cb-derivative, (2) linear arrangement of embryo cells at the tetrad stage, (3) atypical origin of some tiers, and (4) no divisions of the ci and cb cells. A hypothesis about the convergent similarity between the Dienia and Caryophyllaceae types of embryogenesis has been proposed. A number of embryo sac and embryo structures typical for D. ophrydis, including “petassum,” “fitting,” and “suspensor mantle,” have been first described. A “petassum” represents the remains of cell walls of the pollen tube and probably the filamentous apparatus of synergids sealing the micropyle side of a fertilized embryo sac. The sole suspensor cell has a special appendix (“fitting”), which connects it to the embryo. The suspensor and the fitting are surrounded by a special envelope (“suspensor mantle”), which does not cover the basal cell of the embryo (ci).  相似文献   

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We here present a molecular phylogenetic analysis of cultivated Zanthoxylum species which have a long history of cultivation both for economic and for chemical values in China. Three cpDNA markers, including matK, rbcL, and trnL-F, were sequenced, with the goals of untangling phylogenetic relationships and inferring biogeographic origin and patterns of distribution among Zanthoxylum species. Based on three cpDNA markers, 19 haplotypes with 64 polymorphic sites in Zanthoxylum provenances were identified in our study. A low genetic differentiation (G ST ?=?0.271, N ST ?=?0.373) was observed within Zanthoxylum provenances. Based on phylogenetic tree and haplotype network, all 19 haplotypes were grouped into six clusters. Our results also supported the hypothesis that the so-called “Green Huajiao” belongs to the species Zanthoxylum armatum rather than Zanthoxylum schinifolium. The results also revealed that haplotypes of two cultivated species, Zanthoxylum bungeanum and Z. armatum, most probably diverged during the Late Miocene. Ancestral area reconstruction indicated that cultivated Zanthoxylum species experienced multiple long-distance dispersal events and several vicariance events and the ancestors of Zanthoxylum first colonized Yunnan and Guizhou provinces (D). Accordingly, the current disjunct distribution of Z. bungeanum and Z. armatum may represent long-distance dispersal of ancestors popularly named “Dahongpao” and “Qinghuajiao,” respectively. It is concluded that cpDNA markers may provide a new conceptual and practical opportunity to evaluate genetic diversity and to identify local cultivars of Zanthoxylum, making it a valuable source to include into potential breeding programs.  相似文献   

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Sequencing of the fragment of control region in mitochondrial DNA in sculpin Cottus volki and the comparison of obtained data with homologous nucleotide sequences in the other species from genus Cottus demonstrated that C. volki occupies the basal position in the “poecilopus” group, which includes also typical sculpin C. poecilopus Heckel, 1837 from water bodies of Europe, sculpin C. szanaga Dybowski, 1869 from the Amur River basin, and sculpin Cottus cf. poecilopus from the Lena River basin. Early separation of C. volki line from common trunk of “poecilopus” group explains the presence in C. volki of several primitive (plesiomorphic for this group) morphological characters: long interior ray of ventral fin, practically complete lateral body line, and well-developed dentition of palatine bones.  相似文献   

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“Air (aire, also aigre) in the body” is a frequent explanation of illness according to the traditional medical beliefs in Mexico. Anthropologists have generally scrutinized aire in the context of other common folk illnesses treated by traditional healers (curanderas). However, drawing on my research in the communities of Northern Oaxaca I suggest that aire occupies a more distinct position in the folk medical cosmology than it has usually been credited with. This distinction rests on the notion’s exceptional ambivalence and openness to multiple interpretations. “Air” is recurred to as the cause of illness mainly in situations where every other explanation, either “traditional” or “biomedical,” seems to be inadequate. The physical properties of air—its transparency, invisibility, apparent immateriality, near omnipresence, and virtual “nothingness”—render it a suitable explanation of the last resort. Local understandings of what aire “is” are often vague and elusive, and in many respects the term functions in folk medical discourse as an “empty signifier.”  相似文献   

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Upper Triassic Norian reef boulders, exposed in a locality near the fountain “Tavuk Cesme” (“Chicken Fountain”) in Taurus Mountains, southern Turkey yielded a large number of hypercalcified sponges, including “sphinctozoans”, “inozoans”, “spongiomorphids”, and “chaetetids”. The sphinctozoans from this locality are described in this paper. Geologically, this locality belongs to the Anamas-Akseki autochthonous. The reef boulders of this locality are exposed near the “Tavuk Cesme” fountain, located at the road, leading from the town of Aksu to Yenisarbademli. The following taxa are described: Amblysiphonella taurica nov. sp., Anthalythalamia riedeli Senowbari-Daryan, Calabrisiphonella sphaerica nov. sp., Calabrisiphonella cuifi nov. sp., Cinnabaria minima Senowbari-Daryan, Colospongia recta nov. sp., Colospongia sp. 1, Colospongia sp. 2, Colospongia sp. 3, Cryptocoelia compacta nov. sp., Cryptocoelia? sp., Deningeria crassireticulata Senowbari-Daryan, Zühlke, Bechstädt and Flügel, Discosiphonella minima Senowbari-Daryan and Link, Gigantothalamia ovoidalis Senowbari-Daryan, Hajarispongia dipoyrazensis nov. sp., Hajarispongia cortexifera nov. sp., Kashanella irregularis Senowbari-Daryan, Kashanella cylindrica nov. sp., Parauvanella ferdowsensis Senowbari-Daryan, Parastylothalamia cylindrica nov. gen., nov. sp., Asiphothalamia polyosculata nov. gen, nov. sp., Sollasia norica nov. sp., and Thaumastocoelia sphaeroida Senowbari-Daryan. The most abundant sponge is Amblysiphonella taurica nov. sp. followed by Hajarispongia dipoyrazensis nov. sp., Colospongia and Discosiphonella minima Senowbari-Daryan and Link are also relatively abundant. The stylothalamid sponge Parastylothalamia nov. gen. is an abundant sponge genus in other Norian reefs of the Taurus Mountains, but is rare at the “Tavuk Cesme” locality.  相似文献   

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Most commercially important rootstocks for peach [Prunus persica (L.) Batsch] had been selected for resistance to one or more of the root-knot nematode (RKN) species: Meloidogyne incognita, M. arenaria, and M. javanica. The peach root-knot nematode, M. floridensis (MF), is a relatively newly discovered threat to peach and is not controlled by resistance genes in “Nemared,” “Nemaguard,” and “Okinawa.” The “Flordaguard” peach seedling rootstock, conventionally bred to provide resistance to MF, has solely been used for low-chill peach production in Florida for over 20 years and has already shown signs of resistance breakdown. A source of high resistance to the pathogenic MF isolate (“MFGnv14”) was identified from wild peach Prunus kansuensis Rehder (Kansu peach), thereby suggesting the potential for broadening spectrum and increasing durability of resistance in peach rootstocks through interspecific hybridization with P. kansuensis. Using 12 F2 and BC1F1 populations derived from crosses between Okinawa or Flordaguard peach and P. kansuensis populations, we examined the genetic control for MF resistance by identifying associated microsatellite markers and determining genomic location of the resistance locus. One microsatellite marker (UDP98-025) showed strong and consistent association with resistance based on root-galling index. The resistance locus was mapped on the subtelomeric region of linkage group 2, co-localizing with other previously reported RKN resistance genes in Prunus. Segregation of gall-index-based resistance observed in F2 and BC1F1 populations is compatible with the involvement of a multiallelic locus wherein a dominant (Mf1) or recessive (mf3) resistance allele is inherited from P. kansuensis, and susceptibility alleles (mf2) from peach.  相似文献   

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Larvae of three Nymphon species are described. For Nymphon brevirostre Hodge, 1863 and Nymphon micronyx Sars, 1888 protonymphon larvae are examined, larvae of N. micronyx have been studied for the first time. The fine external morphology of larvae is studied in detail using SEM methods; the internal structure of N. brevirostre protonymphon is additionally described. SEM data on external morphology and fine surface structures are given for several postembryonic stages of Nymphon grossipes Fabricius, 1780. Different types of postembryonic development are revealed in examined Nymphon species. N. brevirostre and N. micronyx have a “typical protonymphon” developmental pathway. A special developmental pathway named “lecithotrophic protonymphon” is suggested for N. grossipes and other Nymphonidae having large yolky eggs.  相似文献   

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FLOWERING LOCUS T (FT), a major effect gene, regulates flowering time in Arabidopsis. We analyzed evolutionary changes distinguishing two FT homeologous loci in B. rapa, described genetic variation in homologs isolated and reported expression pattern of FT in B. juncea. Synteny analysis confirmed presence of two FT genomic copies in B. rapa ssp. pekinensis and resolved pre-existing anomalies regarding copy number in “AA” genome. Synteny analysis of B. rapa homeologous regions CR1 (129 kb) and CR2 (232 kb) revealed differential gene fractionation and wide-spread re-arrangements. Seven genomic DNA (gDNA) variants (2.1–2.2 kb) and 10 complementary DNA (cDNA) variants (528 bp) were isolated from 6 Brassica species. The gDNA variants shared 72–99 % similarity within Brassica and 58–60 % between Arabidopsis and Brassica. FT cDNA variants shared 92–100 % similarity within Brassica and 87 % between Arabidopsis and Brassica. Phylogenetic analysis of FT gDNA, cDNA and protein sequences revealed two major clades, differentiating homologs derived from species containing shared “BB” and “CC” genomes. Phylogram based on Brassica FT gDNA differentiated homeologs derived from AA-LF (Least fractioned) and AA-MF1 (Moderately fractioned) sub-genomes. Analysis of FT expression pattern in B. juncea revealed increasing levels correlating with attainment of physiological maturity; highest levels were detected in older leaves implying conservation in spatio-temporal expression pattern vis-à-vis Arabidopsis. In conclusion, our study reveals that polyploidy in Brassicas resulted in expansion of FT gene copies with homologs charting independent evolutionary course through accumulation of mutations. However, expression domains of FT remained conserved across Brassicaceae to preserve the critical function of FT in controlling flowering time.  相似文献   

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