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郭林 《菌物学报》1993,12(Z1):51-55
本文描述采自河北小五台山的黑粉菌一新种,即寄生在野青茅(Deyeuxia arundinacea(L.) Beauv)上的野青茅黑粉菌(Ustilago deyeuxiae L. Guo)。此种与网优黑粉菌(Ustilago scrobiculata Liro)近似,但野青茅黑粉菌网纹明显,网眼高。并报道三种黑粉菌中国新记录。1)酢浆草黑粉菌(Ustilago oxalidis Ellis&Tracy)寄生于醉浆草(Oxalis corniculata L.),此种是我国首次在酢浆草科(Oxalidaceae)植物上发现的黑粉菌。2)网状黑粉菌(Ustilago polygoni-alati Thirum. & Pavgi)寄生于尼泊尔萝(Polygonum nepalense Meisn.),作者对此种进行了订正研究。3)臭草条黑粉菌(Urocystis melicae (Lagerheim & Liro) Zundel)寄生于细叶臭草(Melica radula Fr.)。  相似文献   

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The results of genome analysis of five hybrids, viz.Elymus patagonicus ×Hordeum procerum, E. patagonicus ×H. tetraploidum, E. angulatus ×H. jubatum, E. angulatus ×H. lechleri, andE. angulatus ×H. parodii, are reported. The genomic constitution ofHordeum tetraploidum andH. jubatum is best given as H1H1H2H2, ofH. lechleri andH. parodii as H1H1H2H2H4H4, ofH. procerum as H1H1H2H2H3H3, and ofElymus patagonicus andE. angulatus as SSH1H1H2H2.  相似文献   

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Androecial development of 13 species belonging to six tribes ofFlacourtiaceae has been investigated. While inScolopieae andFlacourtieae the stamens develop centrifugally, inErythrospermeae, Oncobeae andPangieae they are initiated in a centripetal sequence or a sequence that is neither distinctly centripetal nor centrifugal. The distribution of these developmental patterns coincides with the distribution of other characters (e.g. cyanogenic compounds, salicoid leaf teeth) and therefore supports a split of the family intoFlacourtiaceae s. str. (containing theScolopieae, Homalieae, Prockieae, Flacourtieae, Casearieae andBembicieae) andKiggelariaceae (withErythrospermeae, Oncobeae andPangieae) and is in accordance with results of recentrbcL studies.  相似文献   

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Intergeneric crosses were made between representatives of the genomically-defined generaElymus, Agropyron, Elytrigia, Pseudoroegneria, andThinopyrum. The genomic constitution ofElytrigia repens, the type species ofElytrigia, is shown to be SSH, a genomic combination otherwise found only inElymus. The S genome ofPseudoroegneria has almost always a dominant influence on the morphology of the taxa of which it is a component.Wang (1989) showed that the J genome inThinopyrum and the S genome have considerable homoeology, with a mean c-value of 0.35 in diploid SJ hybrids. A genetic coherence from S to SJe, Je, JeJb, and Jb can be expected, agreeing with the continuous morphologic variation pattern observed. Because of the absence of morphological discontinuities between the taxa,Pseudoroegneria (S),Elymus (SH, SY, sometimes with additional genomes),Elytrigia (SSH, SSHX), andThinopyrum (SJ, SJJ, J) are best treated as a single genus,Elymus, following the generic concept ofMelderis in Flora Europaea and Flora of Turkey. The basic genomic constituents ofElymus will then be the S and/or J genomes.Agropyron, with diploids, tetraploids, and hexaploids based on the P genome is morphologically distinct from other genera inTriticeae. In a few species ofElymus andPseudoroegneria, a P genome is an additional constituent. In these cases the P genome has a negligible morphological influence. Therefore, it seems reasonable to maintainAgropyron as a separate genus.  相似文献   

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The serological reaction of seed proteins provides evidence for a partly new systematic arrangement ofCytisus sect.Trianthocytisus and ofCytisus s.l. Proposed modifications agree with recent advances in morphological taxonomy. Sect.Trianthocytisus includes only two species,C. villosus andC. aeolicus. Its position is central within the genus, and this fact agrees with the proposed retypification ofCytisus (type species:C. villosus).C. emeriflorus, formerly included in the same section, constitutes the monospecific sect.Emeroides, which is intermediate towards the genusLembotropis. This is serologically isolated and includes onlyL. nigricans. It is confirmed thatC. sessilifolius should be removed from the genusCytisus as a monospecific genus:Cytisophyllum Lang which is closely allied toHesperolaburnum and toPodocytisus, the most primitive genera ofGenisteae.  相似文献   

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Three new coccoid zoospore-producing green algae includingAxilococcus clingmanii gen. & spec. nov.,Lautosphaeria monsfumosa gen. & spec. nov., andDictylochloris pulchra spec. nova (Chlorococcales, Chlorophyceae) are described.Dedicated to Prof. DrLothar Geitler on the occasion of his 90th birthday.  相似文献   

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Pseudocercospora cyatheae C. Nakash. & S. Inaba on Cyathea sp. as a new species is described. Three species belonging to the genus Cercospora and allied genera are newly added to the mycoflora of Japan. They are Cercospora armoraciae on Armoracia rusticana, Passalora passaloroides on Amorpha fruticosa, and Pseudocercospora nogalesii on Cytisus scoparius.  相似文献   

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Multivariate analysis of vegetative and reproductive characters was used to examine morphological relatedness amongAntennaria alborosea A. E. Porsild,A. corymbosa E. Nels.,A. marginata Greene,A. microphylla Rydb.,A. parvifolia Nutt.,A. rosea Greene, andA. umbrinella Rydb. Both pistillate and staminate plants were examined. Some of the characters examined were variable in one species, but stable in another (i.e., presence or absence of papillae on the achenes). Our analyses indicate that the seven species are morphologically distinct. It is hypothesized that theA. rosea agamic complex arose through hybridization amongA. corymbosa, A. microphylla, A. umbrinella, and possiblyA. dioica (L.)Gaertn. However, hybridization between the three former species and others, as well as their subsequent morphological responses to different environmental conditions causes confusion in recognizing the taxa.Antennaria angustifolia Rydb.,A. arida E. Nels.,A. confinis Greene,A. scariosa E. Nels.,A. foliacea humilis Rydb.,A. concinna E. Nels., andA. viscidula E. Nels. are considered to represent F 1 hybrids.  相似文献   

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Reexamination ofXanthoria persica, X. polycarpoides, X. lobulata gave evidence, that the thalli of these species are devoid of a lower cortex and rhizinae. Therefore, they do not fit the definition of the genusXanthoria and are transferred toCaloplaca (under the new sectionXanthoriella) asCaloplaca persica, C. polycarpoides, andC. boulyi, respectively. — Details on development, anatomical structure, ecology and distribution are presented.
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郭林 《菌物学报》1995,14(Z1):163-168
本文报道炭黑粉菌一新种,即细叶蒿草炭黑粉菌(Anthracoidea filifoliae L. Guo sp.nov.)和4个我国新记录种:1)角孢炭黑粉菌(A. angulata(H. Sydow) Boidol & Poclt), 2)黍状苔炭黑粉菌(A. paniceae Kukkenen), 3)狼尾草团黑粉菌(Sorosporium penniseti Mundkur)和4)米勒粘孢黑粉菌(Tolyposporium muellerianum (Thuemen) McAlpine)。  相似文献   

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A locally severe crown disease of exotic plantation Eucalyptus trees has been recorded periodically in New Zealand since 1986. Symptoms include leaf spots, petiole infection and twig and small branch lesions. Outbreaks of disease are episodic and individual trees may show marked variation in crown symptoms ranging from unaffected to total defoliation. Two previously unknown species of Phytophthora are associated with the disease. These are described and formally designated here as P. captiosa, from Eucalyptus botryoides and E. saligna; and P. fallax, from E. delegatensis, E. fastigata, E. nitens and E. regnans. Both P. captiosa and P. fallax have non-papillate, non-caducous sporangia and both are self-fertile. Phylogenetic analysis on the basis of ITS rDNA sequence data indicates they are closely related to each other but evolutionarily distant from the majority of described Phytophthora taxa. They share a common ancestor with another assemblage of Phytophthora lineages that includes P. insolita, P. macrochlamydospora and P. richardiae. Sporulation of P. captiosa and P. fallax has not been observed in the field. The mode of infection and spread of these non-caducous Phytophthora species in the eucalypt tree canopy remains unknown. This issue, and the possible geographic origins of these two Phytophthora species are discussed.  相似文献   

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A taxonomic revision ofVerbesina sect.Ochractinia is presented. 40 species plus 7 additional infraspecific taxa are recognized. A table of the distribution of the species, key to the species and synonymy are included. Relationships to other sections ofVerbesina and species relationships within sect.Ochractinia are discussed.  相似文献   

15.
Taxonomy of the genus Cristulariella is revised, retaining Cristulariella (Crist.) depraedans as the type. Two new species, Crist. cercidiphylli and Crist. corni, are additionally described under the genus. The new anamorphic genus Hinomyces is erected to accommodate Botrytis (Cristulariella) moricola and Cristulariella pruni. A new genus and species, Nervostroma depraedans, is erected in the Sclerotiniaceae to accommodate the teleomorph of Crist. depraedans, with an additional species, Nervostroma cercidiphylli.  相似文献   

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Polytretophora macrospora is introduced based on specimens from two species ofPandanus in Seychelles. The new species is compared with currently accepted species. A key and a comparative synopsis toPolytetophora species are provided. Numerous specimens ofP. calcarata, collected on members of the Pandanaceae from Australia, Fiji, Hong Kong, Malaysia, New Caledonia, Palau, Philippines, Seychelles and Solomon Islands are also reported, along withP. dendroidea onPandanus sp. from Malaysia.  相似文献   

17.
Oxygen mass transfer represents the most important parameter involved in the design and operation of mixing-sparging equipment for bioreactors. It can be described and analyzed by means of the mass transfer coefficient, kLa. The kLa values are affected by many factors such as geometrical and operational characteristics of the vessels, media composition, type, concentration and microorganism morphology, and biocatalysts properties. The efficiency of oxygen transfer could be enhanced by adding oxygen-vectors in broths, such as hydrocarbons or fluorocarbons, without increasing the energy consumption for mixing or aeration. The experimental results obtained for simulated broths indicated a considerable increase of kLa in the presence of n-dodecane, and the existence of a certain value of n-dodecane concentration that corresponds to a maximum mass transfer rate of oxygen. The magnitude of the positive effect of n-dodecane depends both on the broths characteristics and operational conditions of the bioreactor.Notation d stirrer diameter, mm - d oxygen electrode diameter, mm - D bioreactor diameter, mm - h distance from the inferior stirrer to the bioreactor bottom, mm - H bioreactor height, mm - kLa oxygen mass transfer coefficient, s-1 - l impeller blade length, mm - I oxygen electrode immersed length, mm - P power consumption for mixing of non-aerated broths, W - Pa power consumption for mixing of aerated broths, W - (Pa/V) specific power input, W/m3 - s baffle width, mm - vS superficial air velocity, m/s - V volume of medium, m3 - w impeller blade height, mm - volumetric fraction of oxygen-vector - a apparent viscosity, Pa*s - density, kg/m3  相似文献   

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Thirty-nine species and subspecies of the genera Centaurea, Colymbada, Psephellus and Cyanus (all included in Centaurea s.l.) including many rare and endemic taxa of preponderantly Bulgarian distribution have been investigated with Feulgen DNA image densitometry for holoploid and monoploid genome size (C- and Cx-values). Cyanus varies gradually 2.17-fold between 0.74 pg and 1.56 pg (1Cx). In the remaining taxa two major genome size groups are found, which differ about 1.8-fold in Cx-value. Low values occur in Centaurea subgenera Acrolophus, Solstitiaria, Phalolepis (0.77 pg to 0.90 pg, 1Cx) and Jacea (0.95 pg to 1.09 pg, 1Cx), high values in the genera Colymbada (1.65 pg to 1.93 pg, 1Cx) and Psephellus (1.79 pg, 1Cx, in P. marschallianus). Cx-values support a distinction of Colymbada from Centaurea. Genome size variation is discussed with regard to phylogeny, life form (annual versus perennial), polyploidy, chromosome basic numbers, altitude of occurrence and climate, endemism, and rarity.  相似文献   

19.
Two morphologically similar groups of ascomycetes with globose to subglobose perithecia, elongate necks, unitunicate asci floating freely at maturity, and hyaline ascospores currently placed in Calosphaeria s. lat. and Ceratostomella s. lat., respectively, are studied. The Calosphaeria-like fungi have groups of perithecia growing between cortex and wood, arranged in circular groups with converging necks and piercing the cortex in a common point; the asci with a shallow apical ring and U- to horseshoe-shaped hyaline ascospores are compared with Calosphaeria pulchella, the type species of the genus. Conidiogenesis of the investigated Calosphaeria-like fungi is holoblastic-denticulate; ramichloridium-like and sporothrix-like conidiophores and conidia were formed in vitro. Ascospore and ascus morphology, structure of the ascal apex, ascogenous system, mode of conidiogenesis and the large subunit rRNA sequences of this group differ considerably from C. pulchella and both groups are unrelated. Thus a new genus, Tectonidula, is described with two accepted species, T. hippocrepida and T. fagi; they are separated by ascospore and ascus morphology and holoblastic-denticulate conidiogenesis from the core species of Calosphaeria. The placement of Tectonidula among perithecial ascomycetes is discussed. The relationship of Tectonidula with Barbatosphaeria and two ramichloridium-like hyphomycetous genera Rhodoveronaea and Myrmecridium is investigated. Three species formerly attributed to Ceratostomella are studied. The revision of the herbarium type specimen and fresh material of Ceratostomella ligneola revealed that it is conspecific with Ceratostomella ampullasca and Ceratostomella similis. The LSU phylogeny clearly separated C. ligneola from Ceratostomella s. str. and morphologically similar Lentomitella. On the basis of molecular sequence data and detailed comparison of morphology of asci, ascospores and ascogenous system the genus Natantiella is described for C. ligneola with C. ampullasca and C. similis as its synonyms. Natantiella produced sterile mycelium in vitro.  相似文献   

20.
The gene Brassica campestris male fertility 13 (BcMF13, GenBank accession number EF158459) was isolated as a reproductive organ-specific gene from Chinese cabbage (Brassica campestris L. ssp. chinensis Makino, syn. B. rapa ssp. chinensis). It is exclusively expressed in stage four and five flower buds of fertile lines and is most strongly expressed in stamens. Here, we report a functional characterization of this BcMF13 gene in the antisense-silenced plants. The inflorescence of the BcMF13 mutant was compacted with anthers curved outside. The fertility of this mutant was greatly reduced with less than 5 seeds per silique. Under scanning electron microscopy, the mutant demonstrated numerous shriveled pollen grains with deep invaginations. The frequency of normal pollen grains was just 45.34%. The pollen mother cell, the tetrad, and the mature pollen of the BcMF13 mutant were abnormal resulting in the poor pollen vitality. Germination test in vivo suggested BcMF13 delayed the pollen tubes’ extension in the style. All these indicated BcMF13 had a vital role in pollen development of Chinese cabbage.  相似文献   

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