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1.
Summary  A new monotypic bamboo genus Phuphanochloa (Poaceae: Bambusoideae) from north-eastern Thailand is described, together with a new species, P. speciosa.  相似文献   

2.
Over the past decades there has been a significant increase in fungal infections caused by Candida species, and continues to be common in immunocompromised individuals infected with the human immunodeficiency virus (HIV). Although Candida albicans remains the fungal species most frequently isolated as an opportunistic oral pathogen, other non-albicans are often identified in this cohort of patients, including C. dubliniensis. This yeast is closely related to and shares many phenotypic characteristics with C. albicans. Colonies of these two species appear morphologically identical when not grown on special media. The shared phenotypic characteristics of C. dubliniensis and C. albicans suggest that many C. dubliniensis isolates may have been misidentified as C. albicans in the past. The present studies aim is to recover and identify C. dubliniensis, and presumptive clinical C. albicans, from the oral cavities of HIV-seropositive individuals, comparing conventional media to obtain a simple, low-cost and reliable identification system for C. dubliniensis. A total of 16 isolates (3,98%) had been obtained from 402 HIV infected individuals with recurrent oropharyngitis and were identified as C. dubliniensis. Out of these C. dubliniensis isolates 19% were resistant, with MICs above 64 μg/ml to fluconazole. This constitutes, to the authors knowledge the first recovery of this organism in Venezuela.  相似文献   

3.
A powdery mildew fungus on leaves of Dalbergia cultrata var. cultrata (Fabaceae) collected at the Queen Sirikit Botanical Garden in northern Thailand is proven to be a new species of the genus Brasiliomyces and is described as B. chiangmaiensis sp. nov. with light and SEM micrographs. Differences in known Brasiliomyces species are discussed, and a key to species of this genus is provided.  相似文献   

4.
Summary  Eleven species comprising the Madagascan genus Vaughania are subsumed within the large pantropical genus Indigofera. Six new combinations are made; the remaining species were originally described in Indigofera.  相似文献   

5.
P transposons belong to the eukaryotic DNA transposons, which are transposed by a cut and paste mechanism using a P-element-coded transposase. They have been detected in Drosophila, and reside as single copies and stable homologous sequences in many vertebrate species. We present the P elements Pcin1, Pcin2 and Pcin3 from Ciona intestinalis, a species of the most primitive chordates, and compare them with those from Ciona savignyi. They showed typical DNA transposon structures, namely terminal inverted repeats and target site duplications. The coding region of Pcin1 consisted of 13 small exons that could be translated into a P-transposon-homologous protein. C. intestinalis and C. savignyi displayed nearly the same phenotype. However, their P elements were highly divergent and the assumed P transposase from C. intestinalis was more closely related to the transposase from Drosophila melanogaster than to the transposase of C. savignyi. The present study showed that P elements with typical features of transposable DNA elements may be found already at the base of the chordate lineage. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

6.
Fecundity and feeding of two introduced sibling biological control species, Galerucella calmariensis and G. pusilla (Coleoptera: Chrysomelidae) on purple loosestrife, Lythrum salicaria L. (Lythraceae) were compared at constant temperatures of 12.5, 15, 20, 25, and 27.5 °C. Larval feeding was also carried out at 30 °C, but at this temperature, larvae developed only to the L2 stage and none pupated. Thus, data for this temperature were not used in the analysis. There were significant species × temperature interactions in fecundity. Of the two species, Galerucella pusilla laid more eggs. Although egg production of both species was lowest at 12.5 °C and increased to 20 °C, at higher temperatures, the two species reacted differently. From 25 to 27.5 °C, egg production decreased for G. pusilla, but G. calmariensis fecundity peaked at 27.5 °C. Significant temperature × species × life-stage interactions were also observed in feeding. For each species, the amount of feeding varied with temperature and stage of development. Galerucella pusilla adults consumed more foliage at 15, 20, and 27.5 °C. However, at 12.5 °C G. calmariensis adults fed more than G. pusilla. G. pusilla larvae consumed an average of 25% less foliage than G. calmariensis. The lower larval consumption of G. pusilla suggests that when food is limited, G. pusilla larvae may have a higher survival rate because of its ability to complete larval development with less food and produce more progeny due to its greater fecundity. When food is not limited neither species would have a competitive advantage and both species could coexist temporally and spatially. However, since G. calmariensis larvae consumed more leaf material, the larval stage of this species would have a greater impact on purple loosestrife than G. pusilla.  相似文献   

7.
Four species belonging to Kickxellales (Kickxellomycotina) isolated from soil of Indonesia are described and illustrated. Two new species of Coemansia, C. asiatica and C. javaensis, were discovered in South Sulawesi and West Java, and two known species of Linderina, L. pennispora and L. macrospora, were discovered in East Kalimantan and South Sulawesi, respectively. These four species are newly added to the Indonesian mycobiota. A technique for inducing sporulation of C. javaensis and L. macrospora by adding substances derived from invertebrates such as aphids, nereids, or cladocerans to culture media is described.  相似文献   

8.
Two new species of the fungal genus Trichoderma, Trichoderma compactum and Trichoderma yunnanense, isolated from rhizosphere of tobacco in Yunnan Province, China are described based on morphological characters and phylogenetic analyses of nucleotide sequences. Our DNA sequences included the internal transcribed spacer (ITS) regions of the rDNA cluster (ITS1 and ITS2), and partial sequences of the translation elongation factor 1-alpha (tef1) and a fragment of the gene coding for endochitinase 42 (ech42). The analyses show that T. compactum belongs to the Harzianum clade, and T. yunnanense belongs to the Hamatum clade.  相似文献   

9.
The maT clade of transposons is a group of transposable elements intermediate in sequence and predicted protein structure to mariner and Tc transposons, with a distribution thus far limited to a few invertebrate species. We present evidence, based on searches of publicly available databases, that the nematode Caenorhabditis briggsae has several maT-like transposons, which we have designated as CbmaT elements, dispersed throughout its genome. We also describe two additional transposon sequences that probably share their evolutionary history with the CbmaT transposons. One resembles a fold back variant of a CbmaT element, with long (380-bp) inverted terminal repeats (ITRs) that show a high degree (71%) of identity to CbmaT1. The other, which shares only the 26-bp ITR sequences with one of the CbmaT variants, is present in eight nearly identical copies, but does not have a transposase gene and may therefore be cross mobilised by a CbmaT transposase. Using PCR-based mobility assays, we show that CbmaT1 transposons are capable of excising from the C. briggsae genome. CbmaT1 excised approximately 500 times less frequently than Tcb1 in the reference strain AF16, but both CbmaT1 and Tcb1 excised at extremely high frequencies in the HK105 strain. The HK105 strain also exhibited a high frequency of spontaneous induction of unc-22 mutants, suggesting that it may be a mutator strain of C. briggsae.  相似文献   

10.
We have investigated the floral ontogeny of Arillastrum, Allosyncarpia, Stockwellia and Eucalyptopsis (of the eucalypt group, Myrtaceae) using scanning electron microscopy and light microscopy. Several critical characters for establishing relationships between these genera and to the eucalypts have been determined. The absence of compound petaline primordia in Arillastrum, Allosyncarpia, Stockwellia and Eucalyptopsis excludes these taxa from the eucalypt clade. Post-anthesis circumscissile abscission of the hypanthium above the ovary in Stockwellia, Eucalyptopsis and Allosyncarpia is evidence that these three taxa form a monophyletic group; undifferentiated perianth parts and elongated fusiform buds are characters that unite Stockwellia and Eucalyptopsis as sister taxa. No floral characters clearly associate Arillastrum with either the eucalypt clade or the clade of Stockwellia, Eucalyptopsis and Allosyncarpia.We gratefully acknowledge Clyde Dunlop and Bob Harwood (Northern Territory Herbarium) for collecting specimens of Allosyncarpia, and Bruce Gray (Atherton) for collecting specimens of Stockwellia. The Australian National Herbarium (CANB) kindly lent herbarium specimens of Eucalyptopsis for examination. This research was supported by a University of Melbourne Research Development Grant to Andrew Drinnan.  相似文献   

11.
12.
Floral development in three species each of Leptospermum and Kunzea, and one species of Agonis, is described and compared. Differences in the number of stamens and their arrangement in the flower at anthesis are determined by the growth dynamics of the bud. In Leptospermum, early expansion of the bud is predominantly in the axial direction and causes the stamen primordia to be initiated in antepetalous chevrons. In Kunzea, early expansion occurs predominantly in the lateral direction and successive iterations of stamen primordia are inserted alternately at more or less the same level. In both genera, further expansion in the lateral plane spreads the stamens into a ring around the hypanthium. Agonis flexuosa is similar to Leptospermum. Other variable factors include the timing at which stamen initiation commences (earlier in Leptospermum than Kunzea), the duration of stamen initiation (hence the total number of stamens produced – varies within genera), and very late differential expansion that forces stamens into secondary antesepalous groups in A. flexuosa and L. myrsinoides.The authors thank Dr H. Toelken for kindly providing some material and the impetus for this project. This research was supported by Australian Research Council grant AS19131815.  相似文献   

13.
The complete protocols for long-term micropropagation of some cultivars of four lupin species: Lupinus luteus, L. albus, L. angustifolius and L. mutabilis were elaborated. The shoots were regenerated in vitro via induction of axillary buds development. Plantlets were multiplicated on lowered salts MS-derived media containing BAP in diverse and generally low concentrations. Significant differences in regeneration capacity between species and cultivars were observed. The highest multiplication ratio revealed L. mutabilis and L. luteus. Regenerated shoots were rooted in vitro on low-salts MS-derived media with B5 vitamins. Media were supplemented with different auxins that affected roots formation of particular species and cultivars. Rooting ability of regenerated shoots decreased rapidly through in vitro culture. For that reason, grafting was applied as an alternative method of transfer of shoots to in vivo conditions. This method turned out to be successful for the majority of studied species and cultivars. Complete rooted or grafted plantlets were cultivated in pots with perlit in greenhouse. An erratum to this article is available at .  相似文献   

14.
Summary   Linaria khalkhalensis Hamdi & Assadi is described as a new species from Azerbaijan and Guilan provinces (northern Iran), belonging to Linaria sect. Linaria. It is close to Linaria lineolata Boiss. and L. elymaitica (Boiss.) Kuprian., which it resembles in habit and vegetative features. However, floral and seed characters together with a distinctive geographical distribution, warrant recognition at the species rank. An illustration of the new species, a distribution map, scanning electron micrographs of seed and capsule surfaces, and an identification key are also included.  相似文献   

15.
16.
Flower-visiting beetles belonging to three species of Cetoniidae were collected on three mountains near Beijing, China, and yeasts were isolated from the gut of the insects collected. Based on the 26S rDNA D1/D2 domain and internal transcribed spacer (ITS) region sequence analysis and phenotypic characterization, four novel anamorphic yeast species located in the Candida albicans/Lodderomyces elongisporus clade were identified from 18 of the strains isolated. The new species and type strains are designated as Candida blackwellae AS 2.3639T (=CBS 10843T), Candida jiufengensis AS 2.3688T (=CBS 10846T), Candida oxycetoniae AS 2.3656T (=CBS 10844T), and Candida pseudojiufengensis AS 2.3693T (=CBS 10847T). C. blackwellae sp. nov. was basal to the branch formed by C. albicans and C. dubliniensis with moderately strong bootstrap support. The closest relative of C. oxycetoniae was L. elongisporus. C. jiufengensis sp. nov. and C. pseudojiufengensis sp. nov. were closely related with each other and formed a branch in a subclade represented by C. parapsilosis and L. elongisporus.  相似文献   

17.
18.
Biocontrol of the root-knot nematode Meloidogyne javanica was studied on lentil using plant growth-promoting rhizobacteria (PGPR) namely Pseudomonas putida, P. alcaligenes, Paenibacillus polymyxa and Bacillus pumilus and root nodule bacterium Rhizobium sp. Pseudomonas putida caused greater inhibitory effect on the hatching and penetration of M. javanica followed by P. alcaligenes, P. polymyxa and B. pumilus. Inoculation of any PGPR species alone or together with Rhizobium increased plant growth both in M. javanica-inoculated and -uninoculated plants. Inoculation of Rhizobum caused greater increase in plant growth than caused by any species of plant growth-promoting rhizobacteria in nematode-inoculated plants. Among PGPR, P. putida caused greater increase in plant growth and higher reduction in galling and nematode multiplication followed by P. alcaligenes, P. polymyxa and B. pumilus. Combined use of Rhizobium with any species of PGPR caused higher reduction in galling and nematode multiplication than their individual inoculation. Use of Rhizobium plus P. putida caused maximum reduction in galling and nematode multiplication followed by Rhizobium plus P. alcaligens. Pseudomonas putida caused greater root colonization and siderophore production followed by P. alcaligenes, P. polymyxa and B. pumilus. Analysis of the protein bands of these four species by SDS-PAGE revealed that P. putida had a different protein band profile compared to the protein profiles of P. alcaligenes, P. polymyxa and B. pumilus. However, the protein profiles of P. acaligenes, P. polymyxa and B. pumilus were similar.  相似文献   

19.
Genome sequence analysis of Xanthomonas oryzae pv. oryzae has revealed a cluster of 12 ORFs that are closely related to the gum gene cluster of Xanthomonas campestris pv. campestris. The gum gene cluster of X. oryzae encodes proteins involved in xanthan production; however, there is little experimental evidence supporting this. In this study, biochemical analyses of xanthan produced by a defined set of X. oryzae gum mutant strains allowed us to preliminarily assign functions to most of the gum gene products: biosynthesis of the pentasaccharide repeating unit for GumD, GumM, GumH, GumK, and GumI, xanthan polymerization and transport for GumB, GumC, GumE, and GumJ, and modification of the pentasaccharide repeating unit for GumF, GumG, and GumL. In addition, we found that the exopolysaccharides are essential but not specific for the virulence of X. oryzae. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. Sang-Yoon Kim and Jeong-Gu Kim contributed equally to this work.  相似文献   

20.
The Indo-Pacific marine atherinid fishes Atherinomorus forskalii (Rüppell, 1838), Atherinomorus lacunosus (Forster, 1801), and Atherinomorus pinguis (Lacepède, 1803) are redescribed as valid species based on the types and non-type specimens collected throughout the Indo-Pacific. They are similar to each other chiefly in having a wide midlateral band (almost the same or greater than the midlateral scale width), large mouth (posterior tip of upper jaw reaching to or beyond a vertical through anterior margin of pupil), and no distinct tubercle at the posterior end of the dentary. All three species are distinguishable from congeners by those characters. The three species have long been confused with each other or synonymized erroneously as a single species. Atherinomorus forskalii, known from the Red Sea and eastern Mediterranean, differs from Atherinomorus lacunosus and Atherinomorus pinguis in having conspicuous, large endopterygoid teeth, forming obvious tooth ridges. Atherinomorus lacunosus, widely distributed in almost the entire Indo-Pacific, from East Africa to Tonga, north to southern Japan, and south to northern Australia, differs from Atherinomorus pinguis in having a wider midlateral band (the lower margin reaching to almost the center of the fourth scale row at level of the anal fin origin vs. the lower margin reaching to the ventral end of the third scale row in Atherinomorus pinguis) and more numerous midlateral scales (40–44 vs. 38–41 in Atherinomorus pinguis). Atherina morrisi Jordan and Starks, 1906, Hepsetia pinguis mineri Nichols and Roemhild, 1951, Pranesus capricornensis Woodland, 1961, Pranesus maculatus Taylor, 1964, and Pranesus pinguis ruppelli Smith, 1965, are regarded as junior synonyms of Atherinomorus lacunosus. Atherinomorus pinguis is also widely distributed in the Indo-West Pacific, from East Africa to northern Australia and north to southern Japan. Atherina pectoralis Valenciennes, 1835, is considered a junior synonym of Atherinomorus pinguis. Supplementary material to this paper is available in electronic format at  相似文献   

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