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1.
中国新记录属——裂片茶渍衣属及一个中国新记录种   总被引:1,自引:1,他引:0  
对中国新记录属裂片茶渍衣属(Lobothallia (Clauzade&Cl.Roux) Hafellner)、中国新记录种粉盘裂片茶渍(Lobothallia alphoplaca (Wahlenb.) Hafellner)进行了详细的描述。裂片茶渍衣属地衣体裂片状、龟裂状和鳞片状,被粉芽;子囊盘集中于中部,茶渍型。描述了粉盘裂片茶渍的形态、化学特征和生境,并提供了相关彩色图片。  相似文献   

2.
吕蕾  任强  孙立彦  杨芳  赵遵田 《广西植物》2009,29(3):311-313
在对甘肃白龙江流域的茶渍属(Lecanora)地衣进行调查采集和鉴定的基础上,报道三个中国新记录种:暗灰茶渍(L.cinereofusca H.Magn),暗黄茶渍(L.flavidofusca Mll.Arg.)和颗粒茶渍(L.perplexa Brodo)。对每种给出了详尽的形态、解剖和化学特征描述,并提供了每种的外部形态照片。  相似文献   

3.
对中国新记录属裂片茶渍衣属(Lobothallia (ClauzadeCl.Roux) Hafellner)、中国新记录种粉盘裂片茶渍(Lobothallia alphoplaca (Wahlenb.) Hafellner)进行了详细的描述。裂片茶渍衣属地衣体裂片状、龟裂状和鳞片状,被粉芽;子囊盘集中于中部,茶渍型。描述了粉盘裂片茶渍的形态、化学特征和生境,并提供了相关彩色图片。  相似文献   

4.
对采自陕西太白山地区的中国茶渍属Lecanora地衣多孢种类进行了初步研究,报道三个中国新记录种:多孢茶渍L.bruneri,亚多孢茶渍L.cateilea和日本茶渍L.japonica。以往在中国发现的茶渍属地衣种类子囊均含有8孢,新报道的三种子囊中孢子常多于8个。本文中对每种都给出了详尽的形态、解剖和化学特征描述,并且提供了每种的外部形态照片和日本茶渍的多孢子囊显微照片。  相似文献   

5.
通过形态学及化学研究,结合nrDNA ITS序列的系统发育分析,该文报道了茶渍属(Lecanora Ach.)和石蕊属(Cladonia P. Browne)地衣4中国新记录种:莱氏茶渍(Lecanora layana Lendemer)、白头山茶渍(L. baekdudaeganensis B. G. Lee&Hur)、伪银茶渍(L. pseudargentata Lumbsch)和草皮石蕊[Cladonia caespiticia (Pers.) P. Gaertn., B. Mey&Scherb.]。该文对这些物种的分类学特征进行了详细描述,并与相似种进行了对比,同时提供了各种的地理分布图和形态图。这为中国茶渍属和石蕊属地衣物种多样性及资源利用提供了基础资料。  相似文献   

6.
亚沉茶渍亚洲亚种Lecanora subimmersa subsp.asiatica Zahlbr.曾被基于文献研究转隶至平茶渍属(Aspicilia)或处理为亚沉茶渍原亚种L.subimmersa(Fée)Vain.subsp.subimmersa的异名,但模式标本的研究缺乏仍使该变种的概念不清。利用形态学、解剖学和化学等方法对L.subimmersa subsp.asiatica Zahlbr.的模式标本进行了综合研究,发现L.subimmersa subsp.asiatica与滇茶渍[L.oreinoides(Körb.)Hertel&Rambold]的形态特征及次生代谢产物一致,故将L.subimmersa subsp.asiatica作为L.oreinoides的异名处理。依据研究标本,对滇茶渍进行了形态学描述,同时提供了相关形态学图片,澄清了亚沉茶渍亚洲亚种的概念。  相似文献   

7.
文章报道中国茶渍属地衣3个新记录种——亚异茶渍(Lecanora subravida Nyl.)、栎生茶渍(L.quercicola Coppins&P.James)和针叶茶渍(L.coniferarum Printzen),该3个物种均隶属于柳茶渍组(Lecanora saligna group)。该类群主要特征为,朽木生,地衣体龟裂状至疣状或完全不明显,子囊盘黄绿色至棕色或颜色多样,表面具轻微粉霜,主要化学次生代谢产物为松萝酸。本研究使用贝叶斯分析(BI)构建了基于2个基因位点(nrITS,mtSSU)系统发育树,分析了该3种在茶渍属中的进化位置。本研究还对每个种详细描述形态-解剖特征、分布及栖息地等情况,并提供了地衣体、子囊盘及子囊孢子的彩色图片。  相似文献   

8.
平茶渍属(Aspicilia)是地衣型真菌的重要类群之一。该类真菌在干旱、半干旱地区尤为丰富,因此在地处半干旱区的新疆,其分布也极其多样。该研究对采自新疆阿尔泰山南麓可可托海风景区的平茶渍属地衣标本,从形态解剖、化学显色反应及薄层层析法和生境等多个角度进行了综合分析,发现中国新记录种3个,分别为博伊金平茶渍(Aspicilia boykinii)、烟色平茶渍(A.fumosa)和斯氏平茶渍(A.sipeana)。提供了这3个新记录种的外部宏观形态和内部解剖结构彩色图。  相似文献   

9.
对中国地衣新记录种辐射裂片茶渍Lobothallia radiosa(Hoffm.)Hafellner (Megasporaceae)的形态特征、解剖结构、化学特征和生境进行了描述和研究,并提供5幅彩色图片和中国裂片茶渍衣属的分种检索表.  相似文献   

10.
新疆平茶渍属地衣生态分布与地理区系成分分析   总被引:2,自引:0,他引:2  
根据多年的实地调查资料和前人研究资料,对新疆平茶渍属(Aspicilia)地衣的种类以及它们的分布区、区系特征进行了初步研究。结果表明,分布在新疆的平茶渍属地衣共有33种,主要分布在天山、阿勒泰山、昆仑山和准噶尔盆地。根据它们对环境的适应特征和选择性,将新疆平茶渍属地衣的地理区系划分为广布种、环极北极高山种、环极低北极及北方种、北美东部种、中亚种、中国特有种、分布范围不清楚的种等7种类型。同时把新疆平茶渍属地衣的地理分布区域划分为欧亚森林植物亚区、亚洲荒漠植物亚区、青藏高原亚区等三种分布区域。研究还发现分布在阿勒泰山、天山、昆仑山和准噶尔盆地的平茶渍属主要生长在岩石上面,生长基物比较单一。  相似文献   

11.
Chromosome numbers are presented for 32 collections of 29 European blackberry species (Rubus subg.Rubus) from Germany. One species is triploid (2n = 21), 27 species are tetraploid, (2n = 28), and one species is pentaploid (2n = 35). Chromosome numbers are reported for the first time ofR. adspersus, R. amisiensis, R. calvus, R. conothyrsoides, R. contractipes, R. demissus, R. elegantispinosus, R. ferocior, R. foliosus, R. hypomalacus, R. leucandrus, R. nemorosus, R. platyacanthus, R. praecox, R. rhombifolius, andR. rhytidophyllus. Chromosome numbers forR. dasyphyllus, R. gelertii, R. glandithyrsos, R. lamprocaulos, R. lindebergii, R. macrophyllus, R. montanus, R. muenteri, R. pedemontanus, R. polyanthemus, R. senticosus, R. silvaticus, andR. vigorosus are confirmed.  相似文献   

12.
The detection threshold (DeltaR(50)) of resistive (R) loads is a function of the total background resistance (R(0)). Increased R(0) increases the DeltaR(50), but the ratio DeltaR(50)/R(0) remains constant. The respiratory-related evoked potential (RREP) is elicited only by R loads greater than the cognitive detection threshold, DeltaR(50). We hypothesized that the RREP Nf, P1, and N1 peaks will be elicited only when the added load DeltaR/R(0) is greater than the normal detection threshold, DeltaR(50)/R(0) = 0.30. We also hypothesized that when the R(0) is increased by adding extrinsic R, the RREP will not be elicited if the DeltaR/R(0) is less than the 0.30 ratio. RREPs were recorded with healthy volunteers (n = 20) respiring through a non-rebreathing valve. Three inspiratory R loads that spanned the DeltaR(50)/R(0) = 0.30 detection threshold were presented in two conditions: 1) no added R(0) (R1 < 0.30, R2 > 0.30, R3 > 0.30); and 2) increased R(0) = 13.3 cmH(2)O.l(-1).s (R1 < 0.30, R2 < 0.30, R3 > 0.30). For the control R(0), P1, Nf, and N1 peaks of the RREP were elicited by both R2 and R3, and not present with R1. The increased R(0) decreased R2/R(0) > 1.5 to R2/R(0) < 0.15. With increased R(0), the R1 and R2 loads did not elicit the RREP, but the Nf, P1, and N1 peaks were present for R3. These results demonstrate that the RREP is present if the DeltaR is above the cognitive detection threshold, and the RREP is absent if the load is below the detection threshold. When the R(0) is increased to make the DeltaR/R(0) less than the detection threshold, the DeltaR no longer elicits the RREP.  相似文献   

13.
T E Lobanok 《Genetika》1975,11(5):119-126
The compatibility of four wild type fi+R factors to R1 factor, a representative of the FII compatibility group of F-like class of the plasmids was studied. Two of them (R448 and R459) were incompatible to the R1 factor at selective for R448 and R459 donors conditions. The recipient R1 factor elimination apparently takes place at the first generations of conjugants. The compatibility of these R plasmids to R1 is possible at selective for donor and recipient plasmids conditions. R459 and R1 factors were transfered to Escherichia coli W945 simultaneously and recombination between them was suggested. B211 and R215 factors are compatible to R1 factor and their coexistence with the last is stable despite whether conjugants were selected on one or two R plasmids principle. Further conjugants transfer R211 and R215 only, but not R1. It is concluded that R factors No 448 and No 459 are of FII group compatibility. R211 and R215 factors group compatibility is still unknown.  相似文献   

14.
Recent evidence suggests that stochasticism is important for generating cell type diversity. We have identified a novel stochastic fate choice as part of the mechanism by which Delta/Notch (Dl/N) signaling specifies R7 fate in the Drosophila eye. The equivalence of R1/R6/R7 precursors is normally broken by the activation of N, which specifies the R7 fate. The orphan nuclear hormone receptor Seven-up (Svp) is necessary and sufficient to direct R1/R6/R7 precursors to adopt the R1/R6 fate. A simple model, therefore, is that N represses Svp, which otherwise prevents adoption of the R7 fate. However, we have found that R1/R6s lacking svp stochastically adopt either the R7 or the R8 fate with equal likelihood. We show that N specifies the R7 fate by a novel branched pathway: N represses Svp expression, thereby exposing an underlying stochastic choice between the R7 and R8 fates, and then tips this choice towards the R7 fate.  相似文献   

15.
The inositol 1,4,5-trisphosphate receptors   总被引:8,自引:0,他引:8  
Bezprozvanny I 《Cell calcium》2005,38(3-4):261-272
The inositol (1,4,5)-trisphosphate receptors (InsP3R) are the intracellular calcium (Ca2+) release channels that play a key role in Ca2+ signaling in cells. Three InsP3R isoforms-InsP3R type 1 (InsP3R1), InsP3R type 2 (InsP3R2), and InsP3R type 3 (InsP3R3) are expressed in mammals. A single InsP3R isoform is expressed in Drosophila melanogaster (DmInsP3R) and Caenorhabditis elegans (CeInsP3R). The progress made during last decade towards understanding the function and the properties of the InsP3R is briefly reviewed in this chapter. The main emphasis is on studies that revealed structural determinants responsible for the ligand recognition by the InsP3R, ion permeability of the InsP3R, modulation of the InsP3R by cytosolic Ca2+, ATP and PKA phosphorylation and on the recently identified InsP3R-binding partners. The main focus is on the InsP3R1, but the recent information about properties of other InsP3R isoforms is also discussed.  相似文献   

16.
六种杜鹃花的耐旱适应性研究   总被引:7,自引:0,他引:7  
通过 5 d、1 0 d和 1 5 d灌溉 1次 ,并控制浇水量对露珠杜鹃 ( R. irroratum )、大白花杜鹃 ( R.decorum)、粗柄杜鹃 ( R. pachypodum)、长蕊杜鹃 ( R. stamineum)、马缨杜鹃 ( R. delavayi)以及云锦杜鹃 ( R.fortunei)的耐旱适应性进行了实验 ,实验在昆明 1 0月份到次年 4月份的干季进行 ;灌溉量为每次 1 .5 L/每盆。在实验进行 1 0个月后 ,结果表明 :云锦杜鹃和马缨杜鹃比露珠杜鹃、长蕊杜鹃和粗柄杜鹃耐旱 ,大白花杜鹃最不耐旱  相似文献   

17.
地黄属种间亲缘关系研究   总被引:10,自引:1,他引:9  
闫坤  赵楠  李宏庆 《西北植物学报》2007,27(6):1112-1120
对地黄属6个物种进行了形态解剖学观察、染色体计数、核核糖体内转录间隔区(ITS)序列分析.结果表明,茎的高度、幼叶形态、花萼和花冠形态及颜色、种子千粒重和大小、外种皮网壁厚度、外种皮内侧网纹直径等均是该属内分类的可靠依据.高地黄与裂叶地黄在外部形态及解剖结构的各个方面均极为近似,地黄与茄叶地黄间也存在较大的相似性.茄叶地黄、高地黄、湖北地黄、天目地黄的染色体数目,分别为n=28、14、14、14,确认地黄和茄叶地黄为属内四倍体物种,其余种均为二倍体.ITS测序分析显示,地黄属为单系起源,天目地黄与湖北地黄、高地黄与裂叶地黄、地黄与茄叶地黄构成属内3个分支,与形态学及细胞学研究结果一致.研究认为,天目地黄与湖北地黄有较近的亲缘关系;高地黄和裂叶地黄应为同一物种;地黄与茄叶地黄是属内进化水平最高的类群.  相似文献   

18.
Ribosomal RNA genes are abundant repetitive sequences in most eukaryotes. Ribosomal DNA (rDNA) contains many insertions derived from mobile elements including non-long terminal repeat (non-LTR) retrotransposons. R2 is the well-characterized 28S rDNA-specific non-LTR retrotransposon family that is distributed over at least 4 bilaterian phyla. R2 is a large family sharing the same insertion specificity and classified into 4 clades (R2-A, -B, -C, and -D) based on the N-terminal domain structure and the phylogeny. There is no observation of horizontal transfer of R2; therefore, the origin of R2 dates back to before the split between protostomes and deuterostomes. Here, we in silico identified 1 R2 element from the sea anemone Nematostella vectensis and 2 R2-like retrotransposons from the hydrozoan Hydra magnipapillata. R2 from N. vectensis was inserted into the 28S rDNA like other R2, but the R2-like elements from H. magnipapillata were inserted into the specific sequence in the highly conserved region of the 18S rDNA. We designated the Hydra R2-like elements R8. R8 is inserted at 37 bp upstream from R7, another 18S rDNA-specific retrotransposon family. There is no obvious sequence similarity between targets of R2 and R8, probably because they recognize long DNA sequences. Domain structure and phylogeny indicate that R2 from N. vectensis is the member of the R2-D clade, and R8 from H. magnipapillata belongs to the R2-A clade despite its different sequence specificity. These results suggest that R2 had been generated before the split between cnidarians and bilaterians and that R8 is a retrotransposon family that changed its target from the 28S rDNA to the 18S rDNA.  相似文献   

19.
Planar cell polarity (PCP) is a common feature in many epithelia, reflected in cellular organization within the plane of an epithelium. In the Drosophila eye, Frizzled (Fz)/PCP signaling induces cell-fate specification of the R3/R4 photoreceptors through regulation of Notch activation in R4. Except for Dl upregulation in R3, the mechanism of how Fz/PCP signaling regulates Notch in this context is not understood. We demonstrate that the E3-ubiquitin ligase Neuralized (Neur), required for Dl-N signaling, is asymmetrically expressed within the R3/R4 pair. It is required in R3, where it is also upregulated in a Fz/PCP-dependent manner. As is the case for Dl, N activity in R4 further represses neur expression, thus, reinforcing the asymmetry. We demonstrate that Neur asymmetry is instructive in correct R3/R4 specification. Our data indicate that Fz/PCP-dependent Neur expression in R3 ensures the proper directionality of Dl-N signaling during R3/R4 specification.  相似文献   

20.
Ribonucleoside-diphosphate reductase (EC 1.17.4.1) from Escherichia coli consists of two nonidentical subunits, proteins R1 and R2. The binding of the product dCDP to protein R1 and to the holoenzyme R1R2 has been studied by means of 1H-NMR spectroscopy. In presence of the effector dTTP at 25 degrees C, dCDP was found to be in rapid exchange between the binding sites and the solvent which results in a broadening of the dCDP resonances. When both proteins R1 and R2 are present, so that the complex R1R2 is formed, a smaller broadening is observed than with protein R1 alone. No further linewidth decrease was observed when the [R2]/[R1] ratio exceeded 1. The binding constant of dCDP to R1 or R1R2 is the same, Kd = 0.9 mM. The smaller broadening of the dCDP resonances observed with the complex R1R2 as compared with R1 may be explained by the combination of two effects: (a) the overall tumbling time of the protein will increase when going from R1 to R1R2, which will cause the broadening to increase correspondingly, and (b) a twofold decrease of the number of binding sites in rapid exchange, which will decrease the broadening by a factor of 0.5. The effect of R2 without iron (apoR2) is reduced compared with native R2, probably because of some denatured proteins, while a C-terminal peptide from R2 did not cause any narrowing at all.  相似文献   

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