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1.
Jasminum L. (Oleaceae) consists of \(\sim 200\) species that are distributed in tropical, subtropical and temperate regions of the world. In India, this genus is represented by ca 47 species of which 16 are endemic. Based on the nuclear (internal-transcribed spacer (ITS) region of nrDNA and chloroplast markers (matK, trnL-F and trnH-psbA), phylogenetic relationships in 22 species including one variety of Jasminum in India have been assessed. Maximum likelihood and Bayesian analyses from individual markers, as well as from combined dataset, reveal that the group is monophyletic if Menodora spp. are excluded from the analyses. Our analyses recovered three strongly supported clades. Ancestral character state reconstruction of taxonomically useful characters (leaf forms, leaf arrangement and flower colour) which were used to demarcate sections within the genus reveals homoplasy. Our study suggests that after split from the last common ancestor, there have been at least four reversals to unifoliolate condition. Pinnately compound leaf form evolved at least twice and trifoliolate condition evolved one time only. Alternate leaf form evolved at least twice, once in clade 1 and once in clade 3 and all the time from ancestors having opposite leaf forms. Flower colour evolution clearly depicts that clade 1 is yellow-flowered and clades 2 and 3 have admixture of white and yellow-flowered Jasminum species. Our study suggests that yellow-flowered condition evolved from the white-flowered ancestor. The present study is first to estimate the evolutionary history of Indian Jasmines.  相似文献   

2.
Twelve compounds (112) are isolated from Jasminum lanceolarium Roxb. Among them, compounds 5, 7, 8, 11 and 12 are reported here for the first time from J. lanceolarium, and compounds 6, 9, 10 are firstly isolated from Jasminum genus. The existence of iridoids and lignanoids might be regarded as valuable chemotaxonomic markers for further classification and subdivision of the genus of Jasminum.  相似文献   

3.
García-Mozo  H.  Beltran-Aroca  C. M.  Badu  I. K.  Jimena  I.  Girela-López  E. 《Aerobiologia》2021,37(2):281-291

We report the results of a histological study of lung samples where an unusual quantity of airborne pollen and fungal spores was found in drowned rats. Pollen and spores were found in lungs of drowned rats but not in the post-mortem submerged ones. Another control group consisting of rats that underwent 60 min exposure to a highly pollen-loaded atmosphere also recorded negative for the presence of pollen or fungal spores. Pollen types coincided with plants growing at the surrounding gardens flowering during the days of the experiment, performed during spring, that were detected by the aerobiological trap located at the city. The pollen observed at the lower airways’ tissues were Chenopodiaceae, Cupressus, Ericaceae, Jasminum, Olea europaea, Plantago, Pinus, Poaceae, Quercus and Urticaceae. Regarding fungal spores Alternaria, Aspergillus, Cladosporium cladosporoides, Cladosporium herbarum, Leptosphaeria, Polythrincium and Phitomyces. Pollen and spores’ penetration into deeper regions of the respiratory tract is an unusual phenomenon not happening in regular breathing conditions. Our results revealed that these particles appeared in a significant number in lung samples of drowned animals probably pushed down from upper airways by the force of water inhalation during drowning. Their presence into alveolar spaces offer a useful forensic evidence in doubtful drowning autopsies, favoured by the characteristic of the sporopollenin (pollen wall) and chitin (fungal spore wall) resistance. Moreover, the presence of these particles in alveoli areas of drowned bodies can help forensics to obtain information about pre-mortem dates and places.

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4.
Chloroplast genome organization, gene order, and content are highly conserved among land plants. We sequenced the chloroplast genome of Trachelium caeruleum L. (Campanulaceae), a member of an angiosperm family known for highly rearranged genomes. The total genome size is 162,321 bp, with an inverted repeat (IR) of 27,273 bp, large single-copy (LSC) region of 100,114 bp, and small single-copy (SSC) region of 7,661 bp. The genome encodes 112 different genes, with 17 duplicated in the IR, a tRNA gene (trnI-cau) duplicated once in the LSC region, and a protein-coding gene (psbJ) with two duplicate copies, for a total of 132 putatively intact genes. ndhK may be a pseudogene with internal stop codons, and clpP, ycf1, and ycf2 are so highly diverged that they also may be pseudogenes. ycf15, rpl23, infA, and accD are truncated and likely nonfunctional. The most conspicuous feature of the Trachelium genome is the presence of 18 internally unrearranged blocks of genes inverted or relocated within the genome relative to the ancestral gene order of angiosperm chloroplast genomes. Recombination between repeats or tRNA genes has been suggested as a mechanism of chloroplast genome rearrangements. The Trachelium chloroplast genome shares with Pelargonium and Jasminum both a higher number of repeats and larger repeated sequences in comparison to eight other angiosperm chloroplast genomes, and these are concentrated near rearrangement endpoints. Genes for tRNAs occur at many but not all inversion endpoints, so some combination of repeats and tRNA genes may have mediated these rearrangements.  相似文献   

5.
Jasminum spp. is cultivated for their fragrant flowers used in essential oil production and cosmetic uses. An attempt was made to study the temporal variations in floral scent volatiles composition including emitted, free endogenous and glycosyl‐linked volatile compounds from two summer‐blooming species namely, Jasminum auriculatum and Jasminum grandiflorum as well as from two winter‐blooming species namely, Jasminum multiflorum and Jasminum malabaricum. The overall emitted volatile organic compounds (VOCs) were found to be highest when the matrix Porapak Q 80/100 was used with dichloromethane (DCM) as elution solvent. The floral volatile emission from bud to senescence exhibited nocturnal maxima pattern for both the summer‐blooming species. Both the winter‐blooming species emitted its highest concentration at noon. The free endogenous concentrations of all VOCs were low when corresponding emitted concentrations were high. Enzymatic treatment of petal extract revealed that several aromatic volatiles including aromatic alcohols and monoterpenols are synthesized and stored in the flowers as water‐soluble glycosides; these compounds were shown to accumulate in higher amounts in flowers at late bud stage. These findings indicate the utilization of the precursors, i.e. the volatile‐conjugates, through hydrolysis followed by their release as free‐volatiles at flower opening stage. The outcome as a whole suggests a linkage among the temporal pattern of emitted volatiles, free‐endogenous volatiles and glycoside‐bound volatile compounds in all above studied Jasminum spp. and provided an overview of their floral volatilome.  相似文献   

6.
Summary This paper describes five foliicolous fungi imperfecti from Jabalpur in India. It includesPhyllosticta hasijai Agarwal on leaves ofAcacia melanoxylon R. Br. andCercospora anisochilicola Agarwal onAnisochilus eriocephalus, two new species,C. jasminicola Mueller &Chupp onJasminum sp. andC. achyranthina Thirum. &Chupp onAchyranthes aspera L., two new records for the state, andPestalotiopsis glandicola (Cast.)Steyaert onCassia tora L., a new addition to the fungus flora of India.  相似文献   

7.
该文报道了广西维管植物新记录9种,即刻节润楠(Machilus cicatricosa S. Lee)、四瓣马齿苋(Portulaca quadrifida L.)、腺果藤(Pisonia aculeata L.)、阳春山龙眼(Helicia yangchunensis H. S. Kiu)、小鹿藿[Rhynchosia minima(L.) DC.]、白皮素馨(Jasminum rehderianum Kobuski)、宿苞厚壳树(Ehretia asperula Zoll. et Mor.)、卵叶线柱兰(Zeuxine ovalifolia L. Li&S. J. Li)和羽状穗砖子苗(Cyperus javanicus Houtt.)。文中还提供了识别特征和彩色照片,并列出了每个种的标本引证及地理分布。  相似文献   

8.
本研究旨在探究草珊瑚叶和根中萜类化合物的组织特异性分布差异,解析其药效品质差异形成的分子机制。采用液相色谱-质谱联用技术(liquid chromatography-mass spectrometry, LC-MS)和Illumina HiSeqTM高通量测序技术获得草珊瑚[Sarcandra glabra (thunb) naka]叶和根的代谢组学和转录组学数据。代谢组学结果表明参与叶和根中萜类合成的差异代谢物有50个,包括法尼西基半胱氨酸、甘油醛-3-磷酸、甲羟戊酸-5-磷酸等。转录学结果表明差异代谢酶基因有57条,包括ACTCHMGCRMVKDXSKS等,并预测了MYBC2H2AP2/ERF-ERF等7个转录因子参与调控草珊瑚不同组织部位中萜类的合成和积累差异。实时荧光定量PCR (quantitative real-time polymerase chain reaction, qRT-PCR)结果显示,随机选取的8个参与萜类合成的酶基因在草珊瑚不同组织部位中的表达趋势与转录组学测序结果一致。本研究有助于阐明草珊瑚叶和根临床疗效差异形成的分子机制,同时为草珊瑚的资源开发利用奠定基础。  相似文献   

9.
The diversity of fungi in semi-natural grasslands is poorly known, partly due to difficulties in species identification in the field but also because there are few specialists available. Diversity assessments of grassland fungi would be facilitated if a potential surrogate group for fungal diversity could be identified. The aim of this study was to assess whether plant diversity patterns in semi-natural grasslands are congruent with diversity patterns of Waxcap (Hygrocybe spp.) fungi. Waxcaps, together with several other groups of fungi (e.g. the genera Entoloma, Dermoloma, Camarophyllopsis, and the families Clavariaceae and Geoglossaceae) have habitat requirements similar to many plants typical for semi-natural grasslands and they are all threatened by ceased management and nutrient enrichment. Diversity data from 31 semi-natural grasslands in southern Sweden were used to examine if there is congruence in species richness, nestedness, β-diversity and species composition between plants and Hygrocybe fungi. Species richness of Hygrocybe was significantly positively correlated with plant richness, although the relationship was not strong (r2=0.14). Both plant and Hygrocybe species composition was significantly nested, i.e. species-poor sites contain a subset of species from species-rich sites, which suggests that rare species mostly occur in the species-rich sites. A species similarity analysis between the grassland sites showed that there is low overlap between species composition of plants and Hygrocybe, indicating that conservation decisions based solely on plants may not fulfil the requirements of the Hygrocybe species. The conclusion is that there is low congruence between plant and Hygrocybe species diversity, making plants a poor surrogate group for Hygrocybe fungi, and probably also for other grassland fungi.  相似文献   

10.
Seven tetraploid species ofElymus, viz.E. sibiricus, E. caninus, E. gmelinii, E. semicostatus, E. caucasicus, E. parviglume, andE. longearistatus subsp.canaliculatus, representing five sections were studied morphologically and used in interspecific hybridizations. The aim was to investigate whether the present sectional delimitation of the genus was in agreement with genomic data and if there was a correlation between genome constitution and morphology. The study revealed: (i) further information on the genomic affinities between the different species, (ii) that there is no congruence between genome constitution of the species and current sectional delimitation, and (iii) that there is a correlation between genome constitution and morphology in the palea apex shape and in the size of cilia of the palea.  相似文献   

11.
In the western cordillera of the Cauca valley, Colombia, there is a narrow hybrid zone between two races of Heliconius cydno, one of which is polymorphic. Three large broods show that most of the phenotypic variation observed can be explained by four loci of major effect, named Sb, Yb, L, and K. Two further loci, G and Wo, were identified that control more minor phenotypic variation. Sb, Yb, and Wo are linked and the latter is differentially expressed between the sexes. The transition between H. c. cydnides in the north and H. c. weymeri to the south occurs over approximately 15 km. Collections from a single site near the center of the hybrid zone show that gene frequencies have been stable over the 10 yr from 1991 to 2001 and that color‐pattern genes are in Hardy–Weinberg equilibrium, with little evidence for linkage disequilibrium. This suggests that mating is random between color‐pattern forms. Nonetheless, there is evidence for variation in the sex ratio, with parental phenotypes and the most melanic hybrid phenotypes showing a fairly even sex ratio compared to a strong male bias observed in the remaining hybrids. We hypothesize that this might be explained by differential selection between sexes and phenotypes, phenomena that could have important implications for hybrid zone analysis and the evolution of Müllerian mimicry.  相似文献   

12.
Dothistromin is a polyketide toxin, produced by a fungal forest pathogen, with structural similarity to the aflatoxin precursor versicolorin B. Biochemical and genetic studies suggested that there are common steps in the biosynthetic pathways for these metabolites and showed similarities between some of the genes. A polyketide synthase gene (pksA) was isolated from dothistromin-producing Dothistroma septosporum by hybridization with an aflatoxin ortholog from Aspergillus parasiticus. Inactivation of this gene in D. septosporum resulted in mutants that could not produce dothistromin but that could convert exogenous aflatoxin precursors, including norsolorinic acid, into dothistromin. The mutants also had reduced asexual sporulation compared to the wild type. So far four other genes are known to be clustered immediately alongside pksA. Three of these (cypA, moxA, avfA) are predicted to be orthologs of aflatoxin biosynthetic genes. The other gene (epoA), located between avfA and moxA, is predicted to encode an epoxide hydrolase, for which there is no homolog in either the aflatoxin or sterigmatocystin gene clusters. The pksA gene is located on a small chromosome of ~1.3 Mb in size, along with the dothistromin ketoreductase (dotA) gene.  相似文献   

13.
Aim Phylogenetics has an important role in conservation biogeography. However, there are few data on the phylogenetic diversity of African primates. The phylogenetic diversity (PD) of a species is a measure of its taxonomic distinctness and can be estimated by looking at the phylogenetic relationships among taxa. Species‐specific metrics on PD can then be used to determine conservation priorities at various biogeographical scales. We used PD metrics to rank 55 African primate species according to their conservation priorities at the country level and within six African biogeographical regions. We also addressed the following question: are there differences in conservation rankings between the IUCN Red List and our PD metrics? Location Africa. Methods We created a consensus phylogeny for all African primate clades based on genetic studies. Analyses of species distributions were determined using presence/absence scores at two levels: country and biogeographical region. A node‐based method that standardizes for widespread taxa and endemicity was used to calculate PD indices. Hierarchical cluster analysis was used to convert one of the standardized, phylogenetic indices into three clusters that could be ranked and compared with the main IUCN conservation rankings of endangered, vulnerable, and lower risk. Results At the country and region levels, the top‐priority species in terms of PD are Pan paniscus, Macaca sylvanus, Arctocebus calabarensis, Gorilla beringei, Arctocebus aureus, Allenopithecus nigroviridis, Gorilla gorilla, Procolobus verus, Cercopithecus solatus, Cercocebus galeritus, Colobus angolensis, Theropithecus gelada, Galagoides zanzibaricus, Galagoides granti, and Procolobus (Piliocolobus) badius. Geographic rankings were highest for the Democratic Republic of the Congo (country level) and Central Africa (region level). Although there were no overall differences between IUCN conservation ranks and the PD rankings, there were significant differences between the two systems for vulnerable and endangered primate taxa. Main conclusions There are few ecological and behavioural data on populations of some of the African primates that represent the highest levels of phylogenetic diversity. Studies of primate taxa with high PD rankings should focus on identifying sites suitable for intensive studies of population densities, feeding ecology, and reproductive behaviour. We suggest that PD metrics can serve as an important, complementary data set in the IUCN ranking system for primates.  相似文献   

14.
Bread wheat quality is mainly correlated with high molecular weight glutenin subunits (HMW-GS) of endosperm. The number of HMW-GS alleles with good processing quality is limited in bread wheat cultivars, while there are plenty of HMW-GS alleles in wheat-related grasses to exploit. We report here on the cloning and characterization of HMW-GS alleles from the decaploid Agropyron elongatum. Eleven novel HMW-GS alleles were cloned from the grass. Of them, five are x-type and six y-type glutenin subunit genes. Three alleles Aex4, Aey7, and Aey9 showed high similarity with another three alleles from the diploid Lophopyrum elongatum, which provided direct evidence for the Ee genome origination of A. elongatum. It was noted that C-terminal regions of three alleles of the y-type genes Aey8, Aey9, and Aey10 showed more similarity with x-type genes than with other y-type genes. This demonstrates that there is a kind of intermediate state that appeared in the divergence between x- and y-type genes in the HMW-GS evolution. One x-type subunit, Aex4, with an additional cysteine residue, was speculated to be correlated with the good processing quality of wheat introgression lines. Aey4 was deduced to be a chimeric gene from the recombination between another two genes. How the HMW-GS genes of A. elongatum may contribute to the improvement of wheat processing quality are discussed.  相似文献   

15.

Background  

Coding sequence (CDS) length, gene size, and intron length vary within a genome and among genomes. Previous studies in diverse organisms, including human, D. Melanogaster, C. elegans, S. cerevisiae, and Arabidopsis thaliana, indicated that there are negative relationships between expression level and gene size, CDS length as well as intron length. Different models such as selection for economy model, genomic design model, and mutational bias hypotheses have been proposed to explain such observation. The debate of which model is a superior one to explain the observation has not been settled down. The chicken (Gallus gallus) is an important model organism that bridges the evolutionary gap between mammals and other vertebrates. As D. Melanogaster, chicken has a larger effective population size, selection for chicken genome is expected to be more effective in increasing protein synthesis efficiency. Therefore, in this study the chicken was used as a model organism to elucidate the interaction between gene features and expression pattern upon selection pressure.  相似文献   

16.
The groundwater system in Olkiluoto, Finland, is stratified with a mixing layer at a depth of approximately 300 m between sulphate-rich, methane-poor and sulphate-poor, methane-rich groundwaters. New sequence library data obtained by 454 pyrotag sequencing of the v4v6 16S rDNA region indicated that sulphate-reducing bacteria (SRB) dominated the mixing layer while SRB could not be detected in the deep sulphate-poor groundwater samples. With the indispensable support of the sequence data, it could be demonstrated that sulphate was the only component needed to trigger a very large community transition in deep sulphate-poor, methane-rich groundwater from a non-sulphate-reducing community comprising Hydrogenophaga, Pseudomonas, Thiobacillus, Fusibacter, and Lutibacter to a sulphate-reducing community with Desulfobacula, Desulfovibrio, Desufobulbaceae, Desulfobacterium, Desulfosporosinus, and Desulfotignum. Experiments with biofilms and planktonic microorganisms in flow cells under in situ conditions confirmed that adding sulphate to the sulphate-poor groundwater generated growth of cultivable SRB and detectable SRB-related sequences. It was also found that the 16S rDNA diversity of the biofilms was conserved over 103 d and that there was great similarity in diversity between the microorganisms in the biofilms and in the flowing groundwater. This work demonstrates that the presence/absence of only one geochemical parameter, i.e., sulphate, in the groundwater significantly influenced the diversity of the investigated subterranean microbial community.  相似文献   

17.
Pollen morphology for 12 genera of the Lythraceae is described, using light microscopy (LM), scanning (SEM) and transmission electron microscopy (TEM). The genera surveyed are Haitia, Heimia, Hionanthera, Lafoensia, Lagerstroemia, Lawsonia, Lythrum, Nesaea, Orias (= Lagerstroemia), Pehria, Pemphis, and Peplis. Among results of taxonomic significance are 1) the similarity of pollen between Haitia and Ginoria, suggesting that future classifications reflect a close relationship between these genera, 2) a comparable similarity in pollen between Pehria and Adenaria, 3) the distinction of Hionanthera pollen from that of Ammannia, 4) an exine similar in certain ultrastructural characteristics between Orias and some species of Lagerstroemia, although in general aspect they appear quite different, 5) that within the Didiplis-Lythrum-Peplis complex, there are three palynologically distinct groups, with Didiplis standing apart from the somewhat more similar, but nevertheless, distinct Lythrum and Peplis, and 6) that considerable differences exist between pollen of Pemphis acidula and Pemphis madagascariensis, supporting removal of the latter species to a new genus. This pollen survey is part of a multi-disciplinary effort to clarify generic limits in the Lythraceae, and evaluate relationships within the family and among families of the Myrtales.  相似文献   

18.
19.
广西珍珠湾三种红树林林分土壤碳氮储量的研究   总被引:1,自引:0,他引:1  
为了探讨不同红树林林分土壤有机碳(soil organic carbon,SOC)和全氮(total nitrogen,TN)储量空间的分布特征以及与C/N的相关性,该研究以广西防城珍珠湾红树林湿地为对象,通过样地调查取样和实验室分析,测定了SOC和TN的含量以及土壤碳储量的计量,揭示了广西北仑河珍珠湾秋茄、木榄和混交林三种红树林林分SOC和TN储量空间的分布特征以及C/N与SOC和TN的相关性。结果表明:(1)秋茄、木榄和混交林的SOC储量分别为140.73、124.94、144.71 t·hm-2,三者无显著性差异(P>0.05);木榄和混交林垂直分布特征表现为20~40 cm>0~20 cm>40~60 cm,秋茄表现为随着土层深度的增加而递减。(2)秋茄、木榄和混交林的TN储量分别为6.49、5.01、5.87 t·hm-2,表现为随着土层深度的增加而减少的趋势。(3)秋茄、木榄和混交林的SOC与TN储量之间的相关性极显著(P<0.01),相关系数分别为0.924、0.971和0.844,说明SOC与TN之间存...  相似文献   

20.
Amelanchier bartramiana, which has been shown to be sexual and self-incompatible, and A. laevis, in which apospory and self-compatibility occur, grow in a mixed population in western Maine. Also present there is the putative interspecific hybrid, A. × neglecta. Principal components and canonical discriminant analyses of seven morphological characters from 96 parental and putative hybrid individuals substantiate morphological intermediacy of the hybrids. A Nomarski differential interference microscopy study of megasporogenesis and megagametogenesis in five hybrid plants shows a predominantly aposporous mode of reproduction, and controlled pollinations indicate that seed formation between A. bartramiana and A. laevis is possible and that the hybrids are self-compatible. The hybrids, which are tetraploids (n = ca. 34) like both parents in Maine, produce viable pollen and seed, but there is little evidence for backcrossing with either parent.  相似文献   

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