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1.
Galactoglucomannans were isolated from the lichenized fungi of the genus Parmotrema (Parmotrema austrosinense, Parmotrema delicatulum, Parmotrema mantiqueirense, Parmotrema schindlerii, and Parmotrema tinctorum and that of Rimelia (Rimelia cetrata and Rimelia reticulata) via successive hot alkaline extraction and precipitation with Fehling solution. The structure of each polysaccharide was investigated using 13C NMR and HSQC-DEPT spectroscopy, methylation analysis, and HPSEC-MALLS. The galactoglucomannans had a (1-->6)-linked main chain of alpha-Manp units, substituted preferentially at O-2 and O-4 by alpha-Galp and beta-Galp nonreducing end-units, respectively. The C-1 region of the 13C NMR spectra of these heteropolysaccharides is typical of the lichen species, and is an additional tool in lichenized fungi classification.  相似文献   

2.
报道了中国地衣3新记录种:Porina byssophilaSarcogyne privignaTrimmatothelopsis versipellis,提供了形态学、解剖学、化学特征描述以及地理分布相关信息。  相似文献   

3.
腹枝衣属(Herpothallon)分布在全球热带及亚热带地区,多生于潮湿、避光处。通过野外调查、采集,综合运用形态、解剖和化学等方法对该属地衣进行了分类学研究。发现中国新记录种3个,分别为灰色腹枝衣(H. cinereumG. Thor)、日本腹枝衣(H. japonicum(Zahlbr.) G. Thor)和昆士兰腹枝衣(H. queenslandicum(Elix) Elix)。描述了它们的分类学特征,提供了外部形态图,并编制了中国腹枝衣属地衣的分种检索表。  相似文献   

4.
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   

5.
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   

6.
通过对文字衣科黑文衣属形态学、解剖学、化学与分子生物学的研究,发现中国新记录种1种,即变黄黑文衣(Phaeographis flavescens Dal-Forno&Eliasaro),该种主要特征为地衣体壳状,表面浅黄绿色,无光泽,光滑;子囊盘弯曲,多分支,聚生于假子座中;盘缘黑色,相邻线盘之间有小缝隙,盘面较平坦,黑色,覆有白色粉霜;子囊层无色透明,侧丝顶端分支;子囊含8个子囊孢子;子囊孢子褐色,横隔透镜型,(4~)6胞室,大小19~25.5μm×6~7μm,I+紫红色。该种分布于云南和福建,该研究丰富了对中国黑文衣属物种组成与分布的认知。  相似文献   

7.
通过形态解剖、化学显色反应(CT)及薄层层析法(TLC)对中国地茶属地衣:地茶(Thamnolia vermicularis(Sw.)Ach.ex Schaer.)和雪地茶(Thamnolia subuliformis(Ehrh.)W.L.Culb.)及其种下变型进行了形态分类和特征化合物研究。结果显示,2个变形在形态上均与原变形之间无明显界限,存在过渡形态,并且化学成分也均与原变形一致,因此合并了2个种下变型。通过分析地茶属地衣的分类特征,对地茶属2个种的分类界限进行了重新界定,讨论了我国地茶属的地理分布。  相似文献   

8.
A structural characterization of bound water molecules in the cyclic tetrasaccharide, cyclo-{-->6}-alpha-D-Glcp-(1-->3)-alpha-D-Glcp-(1-->6)-alpha-D-Glcp-(1-->3)-alpha-D-Glcp-(1-->), was carried out by NMR spectroscopy. H-1', 2'-OH, H-3', and 4'-OH of the 3-O-glycosylated residue and H-1 of the 6-O-glycosylated residue were found to cross-relax with protons of bound waters using the double-pulsed field-gradient spin-echo ROESY experiment. In the crystal structure, one water molecule is located in the center of the plate, and its temperature factor is very low, indicating that this water molecule is an intrinsic component.  相似文献   

9.
Summary A simple approach for detecting internal water molecules in proteins in solution is described. This approach combines 19F-detected heteronuclear Overhauser and exchange spectroscopy (HOESY) with site-specific 19F substitution. The model system employed was intestinal fatty acid-binding protein complexed with [2-mono-19F]-palmitate. An intense cross peak was observed between the fluorine and a buried water molecule, as defined in the 1.98 Å crystal structure of the complex. From HOESY spectra, the fluorine-water distance was estimated to be 2.1 Å, in agreement with the crystal structure. This approach may be applicable to macromolecules that are too large for 1H-detected NMR methods.  相似文献   

10.
报道了中国文字衣科地衣一新记录属——裂衣属(Chapsa A.Massal.)及其2新记录种,即印度裂衣(C.indica A.Massal.)和斑果裂衣[C.leprocarpa(Nyl.)A.Frisch],标本来自海南和广西。该属主要特征是:地衣体壳状、树皮生;具子囊盘类或色盘衣类的子囊果,固有果壳融合或不明显,具侧生侧丝;具横隔或砖壁型胞室的子囊孢子。  相似文献   

11.
绒衣属(Coenogonium)地衣属于真菌界(Fungi)子囊菌门(Ascomycota)茶渍纲(Lecanoromycetes)厚顶盘亚纲(Ostropomycetidae)厚顶盘目(Ostropales)绒衣科(Coenogoniaceae),主要分布于热带和亚热带地区。综述了绒衣属地衣研究简史和中国研究概况;报道了中国该属10种地衣,其中1种为中国新记录种:疏羽绒衣(Coenogonium disjunctum)。对各种进行了描述和讨论,并给出了中国绒衣属的检索表和新记录种的图片。这是首次对中国绒衣属地衣的系统研究,为地衣型真菌分类学研究提供了基础资料。  相似文献   

12.
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   

13.
    
Abstract: Development and growth of the three threatened epiphytic lichen species Sticta fuliginosa (Hoffm.) Ach., Leptogium saturninum (Dicks.) Nyl. and Menegazzia terebrata (Hoffm.) Massal. was investigated by low temperature scanning electron microscopy and macro‐photography. Small cotton gauze discs acting as artificial substrata were fixed with aluminium staples on the bark of selected trees and vegetative diaspores (isidia or soredia) were transferred onto these discs. The subsequent development into small thalli of up to 3 mm length was observed within the 32‐month study period. All three species produced anchoring hyphae within the first month after transplantation. Two months later 52 % of the S. fuliginosa diaspores were still on the gauze discs and after 16 months 29 % remained attached. For L. saturninum, the corresponding percentages were 46 % and 19 %, respectively. First lobes resembling adult thalli were observed after 8 to 12 months in S. fuliginosa and L. saturninum but only after 16 months in M. terebrata. All three species developed usually more than one thallus primordium (pseudomeristematic growth zone) per isidium or soredial cluster. Transplanted thallus fragments were able to fix themselves on the new substratum but in all three species large parts degenerated and fell off during the first year, particularly in S. fuliginosa. The results show that the juvenile development of the investigated species is not restricted by microclimatic factors at the study site. We therefore conclude that the juvenile development is not the restricting factor in regard to growth and population survival. Other factors, such as the competition with bryophytes, insufficient diaspore dispersal or forest management practice must account for the small population sizes. The described transplantation technique of vegetative diaspores has proved to be very useful for the augmentation of small populations without damaging the existing thalli and we suggest use of this method for in situ conservation of endangered lichen species.  相似文献   

14.
    
Tree species differ in longevity, canopy structure, and bark texture, chemistry and water storage. Tree species-specific traits play a role in shaping epiphytic vegetation and likely influence the community assembly of organisms feeding on epiphytes. Lichenivorous gastropods, species with calcium-rich shells in particular, need calcium and likely occur more abundantly in and around tree species with high available calcium. We quantified gastropod grazing on the epiphytic lichens Lobaria pulmonaria and Lobaria scrobiculata transplanted to blocks of adjacent trunks of Acer platanoides, Quercus robur and Tilia cordata. We tested the hypothesis that tree species known to have more available Ca, exhibit more grazing damage on transplanted lichens than trees with lower Ca-availability. The grazing pressure was 1.6–1.8 times higher for lichen transplants on Acer and Tilia known to produce litter with easily soluble Ca than on Quercus, which binds Ca as oxalate. Trees with a high grazing pressure on transplants had greater natural abundance of Lobaria virens than of L. pulmonaria. Gastropods preferred L. scrobiculata to L. pulmonaria, evidenced by more observed grazing marks and greater measured biomass loss. We attribute this difference to the lower concentration of carbon-based secondary compounds in L. scrobiculata. However, the strength of the preference varied between the three tree species receiving lichen transplants and was strongest on A. platanoides, while gastropods on T. cordata grazed equal amounts of each transplanted lichen. In conclusion, tree species influenced grazing patterns of gastropods on epiphytic lichens. In addition to bark pH and other factors, we have shown that tree species-specific differences in grazing pressure play a role in shaping the epiphytic macrolichen community.  相似文献   

15.
报道了中国疱衣科疱衣属一新记录种:类喜马拉雅疱衣(Phlyctis subhimalayensis S. Joshi&Upreti),提供了该种的形态特征描述和DNA数据支撑。还对中国已知的疱衣属物种进行了简要描述。同时讨论了近似种,编制了分种检索表,为疱衣属的进一步研究提供了基础资料。  相似文献   

16.
    
We investigated patterns in community composition in Central-European lichen-rich pine forests along a macroclimatic gradient, using two plot sizes. Diversity of lichens, especially the number of boreal and subatlantic taxa per plot increased from southern Slovakia to northern Poland (Baltic Sea). The ecological indicator value for continentality was highest in two inland regions which were characterised by low winter temperatures. Principal coordinates analysis sorted the regions along two major compositional gradients of similar importance, one mirroring the south-to-north gradient and correlating with the Gorczyński index of thermal continentality, and a second correlating with lowest winter temperature. Regional differences driven by macroclimate were the most important determinant of species composition even in small plots. Continentality was of primary importance in assembling terrestrial lichen communities, but its particular components acted differently. Lowest winter temperature appeared to be well connected with ecological meaning of continentality, which is expressed among others in ecological indicator values.  相似文献   

17.
The similarity of lichenized fungal species composition among the 35 floristic regions recognized by Takhtajan was calculated, based on checklists of 132 geographical units and a first draft of a global checklist of lichens and allied fungi (which lists 18,882 species) to assess biogeographic and biodiversity patters of lichenized fungi. A nearest-neighbour cluster analysis of pair-wise comparisons of species composition data (Jaccard index of similarity) from these geographical units is presented. Four main geographical regions were identified: holarctic, subantarctic/Australian, oceanian, and pantropical. Possible changes of the global species number caused by increasing availability of molecular data are discussed. A prospect on future developments of lichen biodiversity research is provided.  相似文献   

18.
从宁夏六盘山区的多个生境中采集了隶属于地卷目(Peltigerales)3科5属的16种地衣,分别为环纹瓦衣(Coccocarpia erythroxyli)、球胶衣(Collema coccophorum)、坚韧胶衣珊瑚变种(C.tenaxvar.corallinum)、砖孢胶衣(C.subconveniens)、亚石胶衣(C.subflaccidum)、亚洲猫耳衣(Leptogiumasiaticum)、伯尔特猫耳衣(L.burneti-i)、猫耳衣(L.menziesii)、土星猫耳衣(L.saturninum)、犬地卷(Peltigera canina)、平盘软地卷(P.elisabethae)、多指地卷(P.polydactylon)、裂芽地卷(P.praetextata)、地卷(P.rufescens)、双孢散盘衣(Solorina bispora)和凹散盘衣(S.saccata)。其中,亚洲猫耳衣和伯尔特猫耳衣为中国北方新分布种,球胶衣为中国西北新分布种,其余13种均为宁夏新记录种。地卷目地衣在六盘山区分布稀少,且表现出对较为阴湿生境的偏好。  相似文献   

19.
Group I introns are commonly reported within nuclear SSU ribosomal DNA of eukaryotic micro-organisms, especially in lichen-forming fungi. We have studied the primary and secondary structure of 70 new nuclear SSU rDNA group I introns of Parmeliaceae (Ascomycota: Lecanorales) and compared them with those available in databases, covering more than 60 species. The analyzed samples of Parmeliaceae fell into two groups, one having an intron at the 1506 site and another lacking this one but having another at the 1516 or 1521 position. Introns at the 1521 position seem to be transposed from 1516 sites. Introns at the 1516 position were similar in structure to ones previously reported at this site and known from other lecanoralean fungi, while those at the 1506 position showed structural differences and no similar introns are known from related fungi. The study of the distribution of group I introns within a large monophyletic ensemble of fungi has revealed an unexpected correlation between intron types and ecological and geographical parameters. The introns at the 1516 position occurred in mainly arctic, boreal, and temperate lichens, while those at position 1506 were present in mainly tropical and subtropical to oceanic mild-temperate taxa. Further, the 1516 introns occurred in genera with few distributed species that could represent older taxa, while the 1506 ones were mainly in species-rich genera that could be of recent speciation, as many species have wide distribution areas. The transition between two different environments has been accompanied by a change in introns gained and lost. [Reviewing Editor: Dr. Debashish Bhattacharya]  相似文献   

20.
Few studies have investigated the genetic diversity of populations of common and widespread lichenized fungi using microsatellite markers, especially the relationships between different measures of genetic diversity and environmental heterogeneity. The main aim of our study was to investigate the population genetics of a widespread and mainly clonally reproducing Usnea subfloridana at the landscape scale, focusing on the comparison of lichen populations within hemiboreal forest stands. Particular attention has been paid to the genetic differentiation of lichen populations in two geographically distinct regions in Estonia and the relationships between forest characteristics and measures of genetic diversity. We genotyped 578 Usnea thalli from eleven lichen populations using seven specific fungal microsatellite markers. Measures of genetic diversity (allelic richness, Shannon's information index, Nei's unbiased genetic diversity, clonal diversity, the number of multilocus genotypes, the number of private alleles, and the minimum number of colonization events) were calculated and compared between Usnea populations. Shared haplotypes, gene flow and AMOVA analyses suggest that unconstrained gene flow and exchange of multilocus genotypes exist between the two geographically remote regions in Estonia. Stand age, mean circumference of the host tree, size of forest site and tree species composition did not show any significant influence on allelic richness, Shannon's information index, Nei's unbiased genetic diversity, clonal diversity, the number of private alleles, and the minimum number of colonization events of U. subfloridana populations. Therefore it was concluded that other factors of habitat heterogeneity could probably have a more significant effect on population genetics of U. subfloridana populations.  相似文献   

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