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1.
Magnolia denudata var. glabrata Y. L. Wang et S. Z. Zhang var. nov. is described and illustrated from Hunan, China. The variety occurs mainly in semi‐evergreen forest of south Hunan at altitudes between 700 and 1260 m a.s.l. It differs from M. denudata var. denudata by its green and glabrous twigs and leaves which are glabrous above and have some white pubescence underneath. With its white flowers consisting of mostly 9 tepals, it differs from M. sprengeri Pamp. which mainly has 12 tepals in various shades of red/pink to white. The new variety is rare and considered endangered due to habitat destruction.  相似文献   

2.
Genkal  S. I.  Kiss  K. T. 《Hydrobiologia》1993,269(1):39-47
Cyclotella atomus collected from different rivers, reservoirs and lakes shows considerable morphological variability. On the basis of electronmicroscopic (EM) study, we propose Cyclotella atomus var. gracilis Genkal et Kiss as a new variety of this species. Cyclotella atomus var. atomus has short and long radial striae, which are irregularly arranged on the same valve, and the alveolar chambers are not clearly divided from the central, hyaline part of the valve face. In addition to the described basic form, several specimens with other features have also been found and are thought to belong to an undescribed variety. The striae of the new variety are equal in length, and the alveolar chambers are clearly divided from the hyaline central area of the valve face by a curved structure.There are EM micrographs on Cyclotella atomus var. gracilis under different names in different papers. The new variety has several characteristics also found in other species, e.g. Cyclotella caspia Grun., or C. meneghiniana Kütz.  相似文献   

3.
Tremacron aurantiacum var. weiningense (Gesneriaceaea), a new variety of Tremacron aurantiacum found in northwest Guizhou, China, is described and illustrated. This new variety differs from T. aurantiacum K. Y. Pan var. aurantiacum in the following respects: it has appressed pubescence and tomentum on the lower surface of its leaves, inflorescence is 4–8‐flowered, 5–10 cymes, peduncles and pedicels are covered with glandular pubescence, the corolla is thin with tube‐like upper lips indistinct and cut‐like, the stigma is 1, capitate.  相似文献   

4.
Flowers from two Eucalyptus camaldulensis trees in the Qutur area and one tree from the Tanta area yielded three isolates of Cryptococcus neoformans var. gattii. Pigeon and sparrow droppings were also investigated for the occurrence of C. neoformans within the study area. Ninety five isolates of the neoformans variety of C. neoformans were recovered from 550 samples of avian droppings. This revised version was published online in October 2005 with corrections to the Cover Date.  相似文献   

5.
Treu  R.  Holmes  D.S.  Smith  B.M.  Astley  D.  Johnson  M.A.T.  Trueman  L.J. 《Plant Ecology》2001,155(2):229-235
Despite the widespread distribution and common habitat dominance of clonal plant species the mechanisms for their ecological success often remain uncertain. Allium ampeloprasum var. babingtonii is a sterile plant that reproduces with physiologically independent asexual propagules. The variety is found mainly in the S.W. of England over a wide habitat range including sea cliffs and open woodlands and displays an autumn-spring phenology in common with its close Mediterranean relatives. The role of population genetic structure in the remarkable habitat distribution of the variety is not known. Genetic variation in A. ampeloprasum var. babingtonii was analysed using RAPD markers in single individuals of var. babingtonii from 16 distinct populations and five further individuals from a single population. This analysis revealed no polymorphism suggesting that all sampled individuals are part of a single clone. We offer the conjecture that in the absence of genetic variation an ecological release, due to temporal separation from competing species, may contribute to the ability of var. babingtonii to exploit heterogeneous environmental conditions.  相似文献   

6.
A new variety of Sporobolomyces salmonicolor, a basidiomycetous yeast isolated from the cerebrospinal fluid of a human case of meningitis has been described. The variety can be differentiated from the species primarily by its ability to assimilate D-galactose and L-arabinose.  相似文献   

7.
One new species, Rhododendron subroseum Xiang Chen & Jiayong Huang, and one new variety, R. denudatum var. glabriovarium Xiang Chen & Xun Chen (Ericaceae), from the Guizhou Province, China are described and illustrated. Rhododendron subroseum is most similar to R. morii from which it differs mainly by having glandular branchlets, a subcordate leaf blade base and a mucronate leaf blade apex, a less floriferous inflorescence, a campanulate to broadly‐campanulate corolla, and a glandular‐hairy style. Rhododendron denudatum var. glabriovarium differs from R. denudatum var. denudatum mainly by having a glabrous ovary. Both of the new taxa are quite rare and therefore their protection is highly desired.  相似文献   

8.
G. I. Naumov 《Microbiology》2000,69(3):338-342
Partial genetic isolation of twoSaccharomyces bayanus varieties, 5.bayanus var.bayanus andS. bayanus var.uvarum comb, nov., was established by hybridological analysis. The hybrids of these two varieties were semisterile: their ascospores were characterized by low survival. Earlier, the new variety was described as a group of cryophilic wine yeast cultivars capable of fermenting melibiose.  相似文献   

9.
One additional species and a variety ofMariannaea, M. camptospora andM. elegans var.punicea, were recorded for the first time in Japan.Mariannaea camptospora formed two types of conidiophores. One type was characterized by simple verticillate phialides sometimes with punctuate walls at the base, producing long oblique conidial chains, and symmetrical spindle-shaped conidia. The other type was characterized by more crowded and shorter phialides with small conidial droplets and hemispherical to concave smaller conidia.Mariannaea elegans var.punicea was characterized by distinct red purple pigmentation in agar media. (55): Udagawa, S. and Uchiyama, S., Mycoscience41: 263–267, 2000.  相似文献   

10.
《Journal of bryology》2013,35(1):38-45
Abstract

New taxonomic observations, based on rhizoidal and protonemal gemmae of material from southern Europe and the Macaronesian Islands, are given in this work for sibling taxa of the Gymnostomum calcareum Nees & Hornsch. complex. Gymnostomum calcareum var. atlanticum Sérgio from the Iberian Peninsula, Madeira and Azores is described as a new variety, and its diagnostic characters are described and illustrated. This moss has a bistratose margin in the upper parts of the perichaetial and vegetative leaves, and the perichaetial leaves are markedly acute. It is closely related to Gymnostomum lanceolatum Cano, Ros & J. Guerra, here reduced to a variety of G. calcareum. The occurrence of fusiform or claviform protonemal gemmae provides a diagnostic feature for the different taxa.  相似文献   

11.
Two new species and one new variety of Elatostema J. R. Forst. & G. Forst. (Urticaceae) are described from Yunnan and Xizang, China. Habitat details and morphological comparison with similar species are given and discussed. The new taxa proposed are: Elatostema densistriolatum W. T. Wang & Zeng. Y. Wu, E. latistipulum W. T. Wang & Zeng Y. Wu and E. cyrtandrifolium (Zoll. & Mor.) Miq. var. hirsutum W. T. Wang & Zeng Y. Wu.  相似文献   

12.
Pinus contorta Douglas ex Loudon var. yukonensis W. L Strong (Yukon pine), a new variety, is described from south–central Yukon, Canada. It is a stout tree with long lower branches, often with paired lower and forked upper stems, and weakly platy to smooth gray bark on the lower stem, when < 70 years old; with bark on the lower stem becoming furrowed and platy on older trees. This contrasts with the narrow columnar habit, simple stem, and scaly bark associated with the more common inland var. latifolia. In several respects, var. yukonensis is more similar to var. contorta (a coastal variant), although occupying a different ecological regime and spatially disjunct (i.e., a high latitude and high elevation variant). Variety yukonensis may represent the taxon alluded to in previous leaf oil terpene and genetic studies, and a possible Beringian survivor.  相似文献   

13.
Summary We deal with a new variety ofAspergillus which we callAspergillus gracilis Bainiervar. sartoryi (Biourge) Batista, Lima and Vital.This variety appears to be very important under the phylogenetic point of view, apparently being an intermediate form betweenAspergillus andPenicillium.Its morphology resemblesA. gracilis but the conidia characteristics are distinct; we took the epithetsartoryi fromA. sartoryi Biourge which was not described by the respective author.We suggest, too, the transfer of the seriesA. restrictus, where we put our new variety, from the groupA. glaucus, to become independant, as a connective series in the phylogenetic development betweenAspergillus andPenicillium, since the type of the series and the other elements that it embraces does not produce sclerotia or cleistothecia and the conidial apparatus offers curious similarity toPenicillium. Besides, some fungi of the series grow well in certain culture media, in complete discordance with the members of the groupA. glaucus.

Publiçacão no 4

Chefe do Instituto de Micologia;

Diretor do Instituto de Antibióticos e Prof. de Microbiologia da Escola de Química;

Assistente micologista do Instituto de Micologia — (Todos da Universidade do Recife).

Os autores declinam o seu agradecimento ao Dr.Heraldo da Silva maia, Assistente micologista eD. Marilene Maranhão Moreira, Auxiliar-Técnico, do Instituto de Micologia, pela colaboração que lhes prestaram, durante a realização do presente trabalho.  相似文献   

14.
A native population ofAegilops cylindrica was encountered for the first time in Greece in 1980 (near Kastoria, NW. Greece), completely isolated and at a great distance from its main distribution area. There are morphological and chromosomal, but no protein and esterase pattern differences from otherAe. cylindrica populations. This justifies the recognition of a new variety: var.kastorianum. Our comparative and karyotypic observations support the view thatAe. caudata var.polyathera and not var.caudata (typica) is the possible donor of genome C of the new variety.  相似文献   

15.
A novel HO gene (Uv-HO) was cloned from the Saccharomyces bayanus var. uvarum (abbreviated as S. uvarum in this study) type strain. The coding region of Uv-HO showed relatively high homology (95%) to that of the Sb-HO gene (S. bayanus var. bayanus HO), but not to the HO genes of other Saccharomyces sensu stricto species. However, the 5′ and 3′ non-coding region of Uv-HO showed less similarity (79% and 76% respectively) even to those of the most homologous gene Sb-HO. Motifs of the mating-type control and the cell-cycle control were conserved in the 5′ non-coding region of Uv-HO, but numbers and positions of motifs were different from those of Sb-HO. CHEF-Southern analysis showed that all tested strains of S. bayanus species, including S. uvarum, carried the HO gene on the 1,100-kb chromosome. By HO-typing PCR using mixed primers, which provided a rapid and convenient tool for yeast identification, either the Uv-HO gene or the Sb-HO gene was detected in strains of S. bayanus species, but two strains were found to have both types of HO gene in each genome. These results suggest that S. uvarum has a unique sequence, but might share the same chromosome constitution within S. bayanus species, and that S. bayanus is a heterogeneous species, of which some strains might be natural hybrid.  相似文献   

16.
Rhus coriaria var. zebaria from Duhok/Aqrae, Kurdistan, Iraq is described as a variety new to science. Field expeditions started in spring 2011, continued during 2012 and 2013 with the aim of collecting sumac specimens from different physiographic regions of Kurdistan, Iraq. A total of ten plants for each variety were sampled. An equal number of tagged herbarium specimens were prepared. The holotype was designated and deposited together with other herbarium specimens in the herbarium of the Faculty of Agriculture and Forestry, Univ. of Duhok. Morphological characters of the leaf, inflorescence, flowers, infructescence, and fruit were studied. The pH value of the pericarp in addition to the hilum length was measured. Results were compared with Rhus coriaria L. var. coriaria. The most distinctive feature of the new variety is the dull whitish brown color of the drupe pericarp of var. zebaria as compared to the reddish brown color of the drupe pericarp of var. coriaria. The whitish color of the drupes of var. zebaria, in combination with their larger size, represents diagnostic characters for distinguishing this variety. In contrast, most leaf characters are of little or no taxonomic value in this species. Only shape, apex and marginal teeths of the leaflets show minor differences for separating the two varieties. Female and male inflorescences and flowers characters show no significant differences. Both hilum length and pH value characters may be useful for taxonomic application if mean values are taken in consideration.  相似文献   

17.
Zusammenfassung Rotalia beccarii var. flevensis nov. var. zeigt eine typische Trimorphie (Formen a1, A2 und B). Diese Trimorphie ist der Ausdruck eines Generationswechsels, der mit den Jahreszeiten gleichen Tritt hält. Die B-Form ist die Dauerform im Winter und bildet im Frühjahr durch asexuelle Vermehrung Plasmodiosporen, welche zur A1-Form heranwachsen. Die A1-Form bildet ihrerseits im Sommer die A2-Form, welche gekennzeichnet ist durch den Besitz eines Chromidiums. In dieser Form entwickeln sich die Mikrosporen durch mitotische Teilungen der aus dem Chromidium entstandenen kleinen Kerne, nachdem die Individuen sich enzystiert haben. Die Kopulation der Mikrosporen liefert im Herbst wieder die mikrosphärische B-Form.Ich habe eine ausführliche Studie publiziert über die Fortpflanzung der Foraminiferen in: Siboga-Reports 4, Part II, S. 79–104. Daselbst ist diese Rotalia noch als Pulvinulina repanda angeführt. Für Figuren verweise ich auf diese Arbeit.Mitteilung der Kommission zur biologischen Untersuchung der Zuidersee während der Trockenlegung.  相似文献   

18.
Plagiochila cucullifolia Jack & Steph. var. anomala J. Heinrichs & Gradst. var. nov. is described and illustrated. The new variety is known from a single locality in southern Ecuador and differs from P. cucullifolia var. cucullifolia by the flat, not saccate leaves, somewhat smaller plant size and weaker leaf dentation. According to phylogenetic analyses of 35 nrDNA ITS1 and ITS2 sequences of Plagiochila, the two varieties of P. cucullifolia form a monophyletic lineage and are placed in a well supported clade together with five other species of Plagiochila sect. Hylacoetes: P. dimorpha Lindenb. & Gottsche var. ecuadorica (Inoue) J. Heinrichs, P. flabelliflora Steph., P. patriciae J. Heinrichs & H. Anton, P. macrostachya Lindenb. and P. turgida Herzog. Within Plagiochila, nrITS sequence variation is not concordant with morphological diversification. ITS sequences of Plagiochila cucullifolia s.str. and of P. dimorpha var. ecuadorica differ in only 23 aligned positions whereas two sequences of P. subplana Lindenb. differ in 86 aligned positions. Morphologically, P. cucullifolia s.str. and P. dimorpha var. ecuadorica differ in more than 20 characters and previously these two taxa were placed in separate genera. P. subplana phenotypes show considerable variation in leaf shape and dentation but the extremes are linked by numerous intermediates.  相似文献   

19.
Interspecific alien chromosome addition lines can be very useful for gene mapping and studying chromosome homoeology between closely related species. In this study we demonstrate a simple but robust manner of identifying individual C-genome chromosomes (C5, C8 and C9) in the A-genome background through the simultaneous use of 5S and 25S ribosomal probes on mitotic and meiotic chromosomes of three different Brassica rapa-B. oleracea var. alboglabra monosomic addition lines. Sequential silver staining and fluorescence in situ hybridisation indicated that 18S-5.8S-25S rRNA genes on the additional chromosome C9 are expressed in the A-genome background. Meiotic behaviour of the additional chromosomes was studied in pollen mother cells at diakinesis and metaphase I. In all of the addition lines the alien chromosome was most frequently observed as a univalent. The alien chromosome C5, which carries an intercalary 5S rDNA locus, occasionally formed trivalents that involved either rDNA- or non rDNA-carrying chromosomes from the A genome. In the case of chromosomes C8 and C9, the most frequently observed intergenomic associations involved the regions occupied by 18S-5.8S-25S ribosomal RNA genes. It is possible that not all such associations represent true pairing but are remnants of nucleolar associations from the preceding interphase. Variations in the numbers and distribution of 5S and 25S rDNA sites between cultivars of B. oleracea, B. oleracea var. alboglabra and B. rapa are discussed.This revised version was published online in April 2005 with corrections to Fig. 2.  相似文献   

20.
Streptomyces peucetius var. caesius, obtained from S. peucetius, the daunomycin producing microorganism, by mutagenic treatment, differs from the parent culture by the color of the vegetative and aerial mycelia and by its antibiotic, producing ability. S. peucetius var. caesius accumulates adriamycin in submerged and aerated culture on a medium containing glucose, brewer's yeast, and inorganic, salts both in shake flasks and in stirred fementers. Isolation of the product is performed by solvent extraction, chromatography on buffered cellulose columns, and crystallization as the hydrochloride. The new antitumor agent, adriamycin, is the 14-hydroxv derivative of daunomyein.  相似文献   

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