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1.
Citrus FT (CiFT) cDNA, which promoted the transition from the vegetative to the reproductive phase in Arabidopsis thaliana, when constitutively expressed was introduced into trifoliate orange (Poncirus trifoliata L. Raf.). The transgenic plants in which CiFT was expressed constitutively showed early flowering, fruiting, and characteristic morphological changes. They started to flower as early as 12 weeks after transfer to a greenhouse, whereas wild-type plants usually have a long juvenile period of several years. Most of the transgenic flowers developed on leafy inflorescences, apparently in place of thorns; however, wild-type adult trifoliate orange usually develops solitary flowers in the axils of leaves. All of the transgenic lines accumulated CiFT mRNA in their shoots, but there were variations in the accumulation level. The transgenic lines showed variation in phenotypes, such as time to first flowering and tree shape. In F1 progeny obtained by crossing ‘Kiyomi’ tangor (C. unshiu × sinensis) with the pollen of one transgenic line, extremely early flowering immediately after germination was observed. The transgene segregated in F1 progeny in a Mendelian fashion, with complete co-segregation of the transgene and the early flowering phenotype. These results showed that constitutive expression of CiFT can reduce the generation time in trifoliate orange.  相似文献   

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The aim of this work was to determine the cytogenetic characteristics of Brazilian Lippia alba (Mill) N. E. Brown and Lantana camara Plum. that could be useful for future characterization of these genera. Our analyses revealed that Li. alba has 2n=30 chromosomes consisting of ten metacentric and five submetacentric pairs, while La. camara has 44 metacentric chromosomes. The large blocks of heterochromatin seen in both species suggest an apomorphic condition. Six 45S rDNA sites were detected in both species by fluorescence in situ hybridization (FISH). Two and four 5S rDNA sites were observed in Li. alba and La. camara, respectively. Meiotic analysis revealed a normal chromosomal behaviour. The number of chromosomes and the presence of 45S rDNA and 5S rDNA sites do not exclude a possible polyploid origin. The cytogenetic differences between La. camara and Li. alba may be useful markers for differentiating these species.  相似文献   

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A new Dactylella species, Dactylella alba was isolated from the ascospores of Orbilia alba collected in Wenshan County, Yunnan Province, China. Conidiophores were either not branched or occasionally branched, bearing divergent sterigmata on the tip with single conidium on each. Conidia were elongated ellipsoids, 1–2 septate, mostly 1 septate. By combining the ITS sequence with morphological characteristics, a new anamorphic species is described and illustrated together with its teleomorph.  相似文献   

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Summary   Funastrum rupicola Goyder, a new species of Apocynaceae: Asclepiadoideae from Bolivia, is described and illustrated. The conservation status of this species is assessed.  相似文献   

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Karyotypes of species sects. Linum and Adenolinum have been studied using C/DAPI-banding, Ag-NOR staining, FISH with 5S and 26S rDNA and RAPD analysis. C/DAPI-banding patterns enabled identification of all homologous chromosome pairs in the studied karyotypes. The revealed high similarity between species L. grandiflorum (2n = 16) and L. decumbens by chromosome and molecular markers proved their close genome relationship and identified the chromosome number in L. decumbens as 2n = 16. The similarity found for C/DAPI-banding patterns between species with the same chromosome numbers corresponds with the results obtained by RAPD-analysis, showing clusterization of 16-, 18- and 30-chromosome species into three separate groups. 5S rDNA and 26S rDNA were co-localized in NOR-chromosome 1 in the genomes of all species investigated. In 30-chromosome species, there were three separate 5S rDNA sites in chromosomes 3, 8 and 13. In 16-chromosome species, a separate 5S rDNA site was also located in chromosome 3, whereas in 18-chromosome species it was found in the long arm of NOR-chromosome 1. Thus, the difference in localization of rDNA sites in species with 2n = 16, 2n = 30 and 2n = 18 confirms taxonomists opinion, who attributed these species to different sects. Linum and Adenolinum, respectively. The obtained results suggest that species with 2n = 16, 2n = 18 and 2n = 30 originated from a 16-chromosome ancestor.  相似文献   

7.
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   

8.
Summary   Typhonium stigmatilobatum V. D. Nguyen, a new species from Vietnam, is described and illustrated.  相似文献   

9.
Gymnopilus ombrophilus sp. nov., growing on rotten wood of conifers and hardwoods from Niigata, Japan is described and illustrated. It is characterized by its medium-sized, brownish-orange basidiocarps with a finely squamulose pileus, stipe lacking an annulus, and mild taste, and microscopically by dextrinoid, small, broadly ellipsoid basidiospores. The new species belongs to the section Microspori. The differences between the taxon and similar species are briefly discussed.  相似文献   

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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   

13.
Cortinarius breviradicatus sp. nov., found in deciduous forests, is described and illustrated from Niigata, Japan. It is characterized by its medium-sized to large dark brown basidiocarp, acutely conical pileus, and rooting stipe, and by subglobose to broadly ellipsoid basidiospores. In addition, the extracting solution from its basidiocarps exhibits a strong fluorescence around 400–430 nm in ultraviolet radiation (250 nm), which was observed in a species of Cortinarius sect. Orellani. The new species belongs to the section Orellani. The differences between the new taxon and similar species are briefly discussed.  相似文献   

14.
Seol E  Jung Y  Lee J  Cho C  Kim T  Rhee Y  Lee S 《Plant cell reports》2008,27(7):1197-1206
Notocactus scopa cv. Soonjung was subjected to in planta Agrobacterium tumefaciens-mediated transformation with vacuum infiltration, pin-pricking, and a combination of the two methods. The pin-pricking combined with vacuum infiltration (20-30 cmHg for 15 min) resulted in a transformation efficiency of 67-100%, and the expression of the uidA and nptII genes was detected in transformed cactus. The established in planta transformation technique generated a transgenic cactus with higher transformation efficiency, shortened selection process, and stable gene expression via asexual reproduction. All of the results showed that the in planta transformation method utilized in the current study provided an efficient and time-saving procedure for the delivery of genes into the cactus genome, and that this technique can be applied to other asexually reproducing succulent plant species.  相似文献   

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Mycoses due to yeasts belonging to other genera than Candida have become common in the last years especially in immuno-compromised patients. Species of the anamorphic basidiomycetous yeast genus Trichosporon are such opportunistic human pathogenic yeasts which cause several diseases. In this study, Trichosporon faecale is reported in Germany for the first time. The isolate was taken from a human foot, where it was associated with a tinea pedis. The fungal isolate was identified by investigating the morphology, physiology by a commercial API 32 C-set and molecular data of SSU and LSU rDNA as well as the ITS region.  相似文献   

16.
Summary  A new species of Macroptilium sect. Microcochle (Benth.) J. A. Lackey is herein described from the states of Piauí and Bahia, Brazil. Macroptilium cochleatum is characterized by few-flowered inflorescences, calyx teeth longer than the tube, a tightly four-coiled keel, and linear, patent fruits. The discovery of this unique Macroptilium species, with its distally coiled keel, expands the diagnostic features of the genus. A key to the Brazilian species of sect. Microcochle is provided.  相似文献   

17.
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   

18.
Summary  Three new species are described in Barleria L. sect. Stellatohirta M. Balkwill from tropical Africa: B. aristata from south-central Tanzania, B. aenea from south-western Tanzania and northeast Zambia, and B. purpureotincta from south-western Zambia. Their affinities and conservation status are discussed.  相似文献   

19.
Two new species of Lirula (L. japonica and L. exigua) on Abies mariesii collected in subalpine areas of northern Japan are described as members of Rhytismatales, Discomycetes. Lirula japonica causes needle cast in fir, but L. exigua seems to occur on the needles of physically damaged twigs. Morphological characteristics of both species are discussed.  相似文献   

20.
C-phycocyanin (C-PC) was extracted from fresh Spirulina platensis by deploying a species of non-pathogenic nitrogen-fixing bacteria, namely, Klebsiella pneumoniae. The algal slurry was neither washed nor centrifuged; the bacterial culture was poured into the slurry, the vessel sealed, and crude C-PC extracted after about 24 h. The extraction was clean and efficient, and the purity and concentration of C-PC proved to be of adequate quality.  相似文献   

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