The Indo-Burma Biodiversity Hotspot is renowned for its rich biodiversity,including that of vascular plants.However,the fern diversity and its endemism in this hotspot have not been well understood and so far,the dive...The Indo-Burma Biodiversity Hotspot is renowned for its rich biodiversity,including that of vascular plants.However,the fern diversity and its endemism in this hotspot have not been well understood and so far,the diversity of very few groups of ferns in this region has been explored using combined molecular and morphological approaches.Here,we updated the plastid phylogeny of the Java fern genus Leptochilus with 226(115%increase of the latest sampling)samples across the distribution range,specifically those of three phylogenetically significant species,Leptochilus ovatus,L.pedunculatus,and L.pothifolius.We also reconstructed the first nuclear phylogeny of the genus based on pgiC gene data.Based on molecular and morphological evidence,we identified three new major clades and six new subclades,redefined three existing species,discovered a number of cryptic species of the genus,and elucidated the evolution of the three most variable characters.Our divergence time analyses and ancestral area reconstruction showed that Leptochilus originated in the Oligocene and diversified from early Miocene and 15 dispersal events from lower to higher latitudes are identified.The evolution of three most important morphological characters is analyzed in a context of the new phylogeny.Our analysis showed that 30(59%of total 51)species of Leptochilus occur in Indo-Burma hotspot,24(80%of the 30 species)of which are endemic to this hotspot.We argue that the Indo-Burma hotspot should be recognized as a diversity hotspot for ferns.展开更多
Through investigating the wild ornamental ferns in Guizhou Province, it is found that there are totally 312 species (including variations), 111 genera and 49 families of such resources in this region, which are classi...Through investigating the wild ornamental ferns in Guizhou Province, it is found that there are totally 312 species (including variations), 111 genera and 49 families of such resources in this region, which are classified into terrestrial fern, epiphytic fern, saxicolous fern, vine fern, tree fern and aquatic fern according to their ecological types. The application of ornamental ferns in garden landscaping and development countermeasures are analyzed in this study.展开更多
64 species (including 5 varieties), 30 genera and 24 families of the edible ferns in Guizhou are preliminartiy confirmed, according to the combination of spot investigation and refereuce analySis:the species, gener...64 species (including 5 varieties), 30 genera and 24 families of the edible ferns in Guizhou are preliminartiy confirmed, according to the combination of spot investigation and refereuce analySis:the species, genera and families account for 8.13%, 19.74% and 44.44% of ferns in Guizhou, respectively. The floristic composition characters and resource distribution of 23 kinds of the edible ferns in Guizhou are described.展开更多
Suitable habitat is vital for the survival and restoration of a species.Understanding the suitable habitat range for lycophytes and ferns is prerequisite for effective species resource conservation and recovery effort...Suitable habitat is vital for the survival and restoration of a species.Understanding the suitable habitat range for lycophytes and ferns is prerequisite for effective species resource conservation and recovery efforts.In this study, we took Athyrium brevifrons as an example, predicted its suitable habitat using a Maxent model with 67 occurrence data and nine environmental variables in Northeast China.The area under the curve(AUC) value of independent test data, as well as the comparison with specimen county areal distribution of A.brevifrons exhibited excellent predictive performance.The type of environmental variables showed that precipitation contributed the most to the distribution prediction, followed by temperature and topography.Percentage contribution and permutation importance both indicated that precipitation of driest quarter(Bio17) was the key factor in determining the natural distribution of A.brevifrons, the reason could be proved by the fern gametophyte biology.The analysis of high habitat suitability areas also showed the habitat preference of A.brevifrons: comparatively more precipitation and less fluctuation in the driest quarter.Changbai Mountains, covering almost all the high and medium habitat suitability areas, provide the best ecological conditions for the survival of A.brevifrons, and should be considered as priority areas for protection and restoration of the wild resource.The potential habitat suitability distribution map could provide a reference for the sustainable development and utilisation of A.brevifrons resource, and Maxent modelling could be valuable for conservation management planning for lycophytes and ferns in Northeast China.展开更多
Ferns and lycophytes have remarkably large genomes.However,little is known about how their genome size evolved in fern lineages.To explore the origins and evolution of chromosome numbers and genome size in ferns,we us...Ferns and lycophytes have remarkably large genomes.However,little is known about how their genome size evolved in fern lineages.To explore the origins and evolution of chromosome numbers and genome size in ferns,we used flow cytometry to measure the genomes of 240 species(255 samples)of extant ferns and lycophytes comprising 27 families and 72 genera,of which 228 species(242 samples)represent new reports.We analyzed correlations among genome size,spore size,chromosomal features,phylogeny,and habitat type preference within a phylogenetic framework.We also applied ANOVA and multinomial logistic regression analysis to preference of habitat type and genome size.Using the phylogeny,we conducted ancestral character reconstruction for habitat types and tested whether genome size changes simultaneously with shifts in habitat preference.We found that 2 C values had weak phylogenetic signal,whereas the base number of chromosomes(x)had a strong phylogenetic signal.Furthermore,our analyses revealed a positive correlation between genome size and chromosome traits,indicating that the base number of chromosomes(x),chromosome size,and polyploidization may be primary contributors to genome expansion in ferns and lycophytes.Genome sizes in different habitat types varied significantly and were significantly correlated with habitat types;specifically,multinomial logistic regression indicated that species with larger 2 C values were more likely to be epiphytes.Terrestrial habitat is inferred to be ancestral for both extant ferns and lycophytes,whereas transitions to other habitat types occurred as the major clades emerged.Shifts in habitat types appear be followed by periods of genomic stability.Based on these results,we inferred that habitat type changes and multiple whole-genome duplications have contributed to the formation of large genomes of ferns and their allies during their evolutionary history.展开更多
Despite that several studies have shown that data derived from species lists generated from distribution occurrence records in the Global Biodiversity Information Facility(GBIF)are not appropriate for those ecological...Despite that several studies have shown that data derived from species lists generated from distribution occurrence records in the Global Biodiversity Information Facility(GBIF)are not appropriate for those ecological and biogeographic studies that require high sampling completeness,because species lists derived from GBIF are generally very incomplete,Suissa et al.(2021)generated fern species lists based on data with GBIF for 100 km×100 km grid cells across the world,and used the data to determine fern diversity hotspots and species richness-climate relationships.We conduct an evaluation on the completeness of fern species lists derived from GBIF at the grid-cell scale and at a larger spatial scale,and determine whether fern data derived from GBIF are appropriate for studies on the relations of species composition and richness with climatic variables.We show that species sampling completeness of GBIF is low(<40%)for most of the grid cells examined,and such low sampling completeness can substantially bias the investigation of geographic and ecological patterns of species diversity and the identification of diversity hotspots.We conclude that fern species lists derived from GBIF are generally very incomplete across a wide range of spatial scales,and are not appropriate for studies that require data derived from species lists in high completeness.We present a map showing global patterns of fern species diversity based on complete or nearly complete regional fern species lists.展开更多
We analyzed the distributional patterns of95 selected species of leptosporangiate ferns inhabiting the Mexican Mountain Component, using grid-cells of one geographical degree as unit areas,applying endemism indices an...We analyzed the distributional patterns of95 selected species of leptosporangiate ferns inhabiting the Mexican Mountain Component, using grid-cells of one geographical degree as unit areas,applying endemism indices and richness and beta diversity analyses.Distributional data were obtained from several herbaria and specialized literature.Five grid-cells appear to be important for fern species richness, as they contain 35 to 49 species.These gridcells are located in the Sierra Madre Oriental(SMO),Trans-Mexican Volcanic Belt(TMVB) and the Sierra Madre del Sur(SMS).Mean richness by latitudinal belts of one degree showed that the belts with highest values are related to the TMVB and SMS.A total of 13grid-cells were recognized as important from theperspective of endemism; most of them are located also in the SMO, TMVB and SMS.The richest gridcells coincided with one of the main centres of endemism for ferns obtained in this study, located in the convergence of the southern part of the SMO, the eastern portion of the TMVB and the northern part of the SMS, reflecting the high humidity existing on the mountain slopes facing the Gulf of Mexico.Some important grid-cells recognized from richness and endemism analyses coincide with Mexican Natural Protected Areas.The beta diversity analysis showed a low degree of similarity among grid-cells, implying a high species replacement, as the result of environmental heterogeneity occurring in the Mexican mountain systems.On the other hand, the spatial analysis suggested a pattern of phytogeographical regionalization comprising twomain areas: the Mexican Transition Zone and the Mexican Central Plateau.Ferns play an important role in the Mexican biodiversity and contributing to the beta diversity of Mexico.展开更多
We documented the status of fern diversity, biomass and car- bon accumulation at Chilapatta Reserve Forest in Cooch Behar Wildlife Division, West Bengal. Stratified random nested quadrat sampling was adopted for analy...We documented the status of fern diversity, biomass and car- bon accumulation at Chilapatta Reserve Forest in Cooch Behar Wildlife Division, West Bengal. Stratified random nested quadrat sampling was adopted for analyzing the qualitative and quantitative characters. Nineteen fern species were recorded, of which two are yet to be identified. Identified species were of eight families and nine genera. Highest and lowest frequency recorded were 25.44 and 0.19 while relative frequency varied from 3.16 to 12.25. Fern density ranged from 93 to 13,403 individuals.ha^-1. Most of the species were widely distributed. IVI values ranged from 7.54 to 37.45. The above ground portion of ferns accumulated the major portion ofbiomass and carbon.展开更多
Objective: To investigate the antifungal activity of the fern species Lygodium venustum(L. venustum) and Pityrogramma calomelanos(P. calomelanos) against Candida albicans and Candida tropicalis strains.Methods: The mi...Objective: To investigate the antifungal activity of the fern species Lygodium venustum(L. venustum) and Pityrogramma calomelanos(P. calomelanos) against Candida albicans and Candida tropicalis strains.Methods: The microdilution method was used to evaluate the antifungal activity, as well as the modulating effects of ethanolic extracts of these plants in combination with fluconazole. The minimum inhibitory concentration(MIC), minimum fungicide concentration and morphological changes were also determined.Results: The extract obtained from L. venustum presented a MIC > 8 192 mg/m L, while the extract obtained from and P. calomelanos presented a MIC = 8 192 mg/m L, indicating that they present weak antifungal activity. However, combination of the extracts with Fluconazole potentiated the antifungal activity of this drug. At different experimental conditions, such as concentration of the extract and type of strain, the extracts inhibited hyphae and pseudohyphae formation, indicating that these fern species can affect the morphology of the fungi.Conclusions: The extracts obtained from the fern species L. venustum and P. calomelanos dose not present significant antifungal activity. However, P. calomelanos potentiates the activity of fluconazole and both extracts inhibits the morphological changes in Candida species, indicating that they have potential pharmacological activity as modulators of fungal biology. Therefore, novel studies are required to characterize the interference of these extracts in the virulence and pathogenicity of Candida species as well as the potential of fern species to treat fungal infections.展开更多
In order to fully understand the distribution characteristics and geographical elements of fern flora and to reveal their process of natural history, the present study analyzed the floristic composition and geographic...In order to fully understand the distribution characteristics and geographical elements of fern flora and to reveal their process of natural history, the present study analyzed the floristic composition and geographical distribution of ferns in grassland of Gansu Province. The results showed that there were 31 species of ferns in grassland of Gansu, belonging to 19 genera and 14 families. The investigated ferns accounted for 22.22%, 8.26% and 1.99% of total families (63), total genera (230) and total species (2 600) of ferns resources, respectively. The dominant families were Dryopteridceae and Polypodiaceae; the dominant genera were Selaginella and Woodsia. Families mainly belonged to tropical distribution type and genera mainly belonged to tropical and temperate distribution type without endemic genus. Vertical distribution was obvious ; plant components contained old families and genera. The richness of fern in Gansu grassland was not high.展开更多
Using a mixed culture of megaspores and microspores from I. coreana, we established high frequency sporophyte regeneration system. After 20 days of culturing in MS basal medium, microscopic examination showed signific...Using a mixed culture of megaspores and microspores from I. coreana, we established high frequency sporophyte regeneration system. After 20 days of culturing in MS basal medium, microscopic examination showed significant morphological changes and the microspore released numerous small vesicles into the culture medium. Megaspores also showed dramatic morphological changes during its incubation time in culture. The spore wall was cracked by the expansion of the megaspore (about 2 times increase in diameter). Simultaneously, brown spots were observed on the surface of the megaspores. The frequency of female gametophytes developing from immature megaspores cultured in MS basal liquid medium (pH 7) supplemented with 1 mgl-1 GA3 was 46%. However, these female gametophytes derived from megaspore only culture could not differentiate into sporophytes. The mixed culture of microspores and megaspores resulted in successful sporophyte regeneration. The highest frequency (12.3%) of green sporophyte regeneration from mixed spore culture occurred when the cultures were maintained at 25℃ under cool-white fluorescent light (40 μmol·m-2·s-1) with a 16 h photoperiod. Regenerated sporophytes were transferred to a test tube containing vermiculite and a sand mixture and left there until they had three leaves. After root growth and the fifth leaf had emerged, more than 95% of the regenerated sporophytes were successfully transferred to the soil and grown to mature plants. The sporophyte regeneration system established in this study could be successfully used for the restoration of the endangered aquatic species, I. coreana.展开更多
The present work focuses on the development of a novel computer-based approach for tear ferning(TF)featuring.The original TF images of the recently developedfive-point grading scale have been used to assign a grade fo...The present work focuses on the development of a novel computer-based approach for tear ferning(TF)featuring.The original TF images of the recently developedfive-point grading scale have been used to assign a grade for any TF image automatically.A vector characteristic(VC)representing each grade was built using the reference images.A weighted combination between features selected from textures analysis using gray level co-occurrence matrix(GLCM),power spectrum(PS)analysis and linear specificity of the image were used to build the VC of each grade.A total of 14 features from texture analysis were used.PS at di®erent frequency points and number of line segments in each image were also used.Five features from GLCM have shown significant di®erences between the recently developed grading scale images which are:angular second moment at 0and 45,contrast,and correlation at 0and 45;thesefive features were all included in the characteristic vector.Three specific power frequencies were used in the VC because of the discrimination power.Number of line segments was also chosen because of dissimilarities between images.A VC for each grade of TF reference images was constructed and was found to be significantly different from each other's.This is a basic and fundamental step toward an automatic grading for computer-based diagnosis for dry eye.展开更多
[Objectives] This study was conducted to optimize the extraction process of luteolin, a natural product of Ternate Grape Fern Herb, so as to provide a theoretical research basis for the chemical composition, pharmacol...[Objectives] This study was conducted to optimize the extraction process of luteolin, a natural product of Ternate Grape Fern Herb, so as to provide a theoretical research basis for the chemical composition, pharmacological research and preparation development of Ternate Grape Fern Herb. [Methods] The effects of four factors including ultrasonic extraction time, liquid-to-material ratio, ultrasonic extraction temperature and ethanol concentration on extraction yield of luteolin from Ternate Grape Fern Herb were investigated by the ultrasonic-assisted extraction technology, through a single-factor experiment and an orthogonal experiment based on the single-factor experiment, and the experimental data was subjected to variance analysis and SSR analysis of the significance of differences between groups by SPSS20.0 software to select the optimal extraction process conditions. [Results] The optimal extraction process conditions were as follows: ultrasonic extraction time 25 min, liquid-to-material ratio 25∶1 ml/g, ethanol volume fraction 60%, ultrasonic extraction temperature 85 ℃. [Conclusions] The results were verified, and it was determined that the ultrasonic-assisted extraction process established in this study is reasonable and reliable, and can be used for the extraction of luteolin.展开更多
Objective To evaluate the saliva ferning test (SFT) as diagnostic test for xerostomia in patients with Sjogren’s Syndrome (SS). Methods In this study, dried samples of freshly produced saliva from 78 patients with es...Objective To evaluate the saliva ferning test (SFT) as diagnostic test for xerostomia in patients with Sjogren’s Syndrome (SS). Methods In this study, dried samples of freshly produced saliva from 78 patients with established SS according to European Community criteria and 80 healthy controls were examined by light microscopy. The crystallization was classified into 4 types according to the ferning phenomenon: uniformity, branching, spreading and integrity (type I normal and type Ⅱ,Ⅲ,Ⅳ abnormal ). Then, the 78 patients underwent lebial salivary gland biopsy. According to Tarpley’s classifica- tion, minor salivary gland biopsy (≥2 + ) was considered to be positive . Results 1. The sensitivity of SFT was high (70/ 78 = 89. 74% ). And the specificity wes also high (67/80 = 83. 75% ). 2. Abnormal SFT was observed in 70/78 (89. 74% ) samples from patients group and in 13 /80 (16. 25% ) samples from healthy controls. The differences of SFT in patients group versus controls were statistically significant (P< 0. 01 ). 3. The sensitivity of SFT and mini labial gland biopsy had no significant differences (P > 0. 05) as diagnostic tests in SS. Conclusion SFT was simple, sensitive and specific as diagnostic test in SS suspect patients just as mini labial gland biopsy.展开更多
This study describes the anatomy of sterile leaves of Elaphoglossum discolor (Kuhn) C. Chr., E. flaccidum (Fée) T. Moore and E. laminarioides (Bory ex Fée) T. Moore, the most representative species of the ge...This study describes the anatomy of sterile leaves of Elaphoglossum discolor (Kuhn) C. Chr., E. flaccidum (Fée) T. Moore and E. laminarioides (Bory ex Fée) T. Moore, the most representative species of the genus in the Ecological Park of Gunma in Pará State. It reports the main diagnostic characters and provides new systematic data for the group. In addition, it locates the production and accumulation sites of bioactive compounds to determine possible adaptive strategies of these species in the Amazon rainforest environment. Diagnostic structural features include stoma typology, central veins and margin forms, type of mesophyll, and the presence of schlerenchymatous sheaths in the cortex, among others. Among the bioactive compounds related to defense adaptation are phenolic compounds, which occur in all three species, and alkaloids and mucilage, which are exclusive to E. laminarioides. Of the three species studied, E. laminarioides has features that make it the best suited to the rainforest environment.展开更多
基金supported by the Second Tibetan Plateau Scientific Expedition and Research(STEP)program(2019QZKK0502)a grant from Yunnan Fundamental Research Projects(Grant#202201BC070001)a Yunnan Revitalization Talent Support Program“Young Talent”Project and a CAS Scholarship to Liang Zhang.
文摘The Indo-Burma Biodiversity Hotspot is renowned for its rich biodiversity,including that of vascular plants.However,the fern diversity and its endemism in this hotspot have not been well understood and so far,the diversity of very few groups of ferns in this region has been explored using combined molecular and morphological approaches.Here,we updated the plastid phylogeny of the Java fern genus Leptochilus with 226(115%increase of the latest sampling)samples across the distribution range,specifically those of three phylogenetically significant species,Leptochilus ovatus,L.pedunculatus,and L.pothifolius.We also reconstructed the first nuclear phylogeny of the genus based on pgiC gene data.Based on molecular and morphological evidence,we identified three new major clades and six new subclades,redefined three existing species,discovered a number of cryptic species of the genus,and elucidated the evolution of the three most variable characters.Our divergence time analyses and ancestral area reconstruction showed that Leptochilus originated in the Oligocene and diversified from early Miocene and 15 dispersal events from lower to higher latitudes are identified.The evolution of three most important morphological characters is analyzed in a context of the new phylogeny.Our analysis showed that 30(59%of total 51)species of Leptochilus occur in Indo-Burma hotspot,24(80%of the 30 species)of which are endemic to this hotspot.We argue that the Indo-Burma hotspot should be recognized as a diversity hotspot for ferns.
文摘Through investigating the wild ornamental ferns in Guizhou Province, it is found that there are totally 312 species (including variations), 111 genera and 49 families of such resources in this region, which are classified into terrestrial fern, epiphytic fern, saxicolous fern, vine fern, tree fern and aquatic fern according to their ecological types. The application of ornamental ferns in garden landscaping and development countermeasures are analyzed in this study.
基金Supported by Guiyang Science and Technology Planning Project~~
文摘64 species (including 5 varieties), 30 genera and 24 families of the edible ferns in Guizhou are preliminartiy confirmed, according to the combination of spot investigation and refereuce analySis:the species, genera and families account for 8.13%, 19.74% and 44.44% of ferns in Guizhou, respectively. The floristic composition characters and resource distribution of 23 kinds of the edible ferns in Guizhou are described.
基金Under the auspices of National Key Research and Development Program of China(No.2016YFC0500300)National Natural Science Foundation of China(No.41675153)
文摘Suitable habitat is vital for the survival and restoration of a species.Understanding the suitable habitat range for lycophytes and ferns is prerequisite for effective species resource conservation and recovery efforts.In this study, we took Athyrium brevifrons as an example, predicted its suitable habitat using a Maxent model with 67 occurrence data and nine environmental variables in Northeast China.The area under the curve(AUC) value of independent test data, as well as the comparison with specimen county areal distribution of A.brevifrons exhibited excellent predictive performance.The type of environmental variables showed that precipitation contributed the most to the distribution prediction, followed by temperature and topography.Percentage contribution and permutation importance both indicated that precipitation of driest quarter(Bio17) was the key factor in determining the natural distribution of A.brevifrons, the reason could be proved by the fern gametophyte biology.The analysis of high habitat suitability areas also showed the habitat preference of A.brevifrons: comparatively more precipitation and less fluctuation in the driest quarter.Changbai Mountains, covering almost all the high and medium habitat suitability areas, provide the best ecological conditions for the survival of A.brevifrons, and should be considered as priority areas for protection and restoration of the wild resource.The potential habitat suitability distribution map could provide a reference for the sustainable development and utilisation of A.brevifrons resource, and Maxent modelling could be valuable for conservation management planning for lycophytes and ferns in Northeast China.
基金the National Natural Science Foundation of China(grant number 31870188,31800174,31700172,41571056)to Wang,Shen,Wang and XingShanghai Landscaping and City Appearance Administrative Bureau of China,Scientific Research Grants(G182411)to Yan+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(grant number XDA13020603,XDA13020500)to Chen and JianGuangdong Natural Science Foundation(grant number 2015A030308015)to Wang。
文摘Ferns and lycophytes have remarkably large genomes.However,little is known about how their genome size evolved in fern lineages.To explore the origins and evolution of chromosome numbers and genome size in ferns,we used flow cytometry to measure the genomes of 240 species(255 samples)of extant ferns and lycophytes comprising 27 families and 72 genera,of which 228 species(242 samples)represent new reports.We analyzed correlations among genome size,spore size,chromosomal features,phylogeny,and habitat type preference within a phylogenetic framework.We also applied ANOVA and multinomial logistic regression analysis to preference of habitat type and genome size.Using the phylogeny,we conducted ancestral character reconstruction for habitat types and tested whether genome size changes simultaneously with shifts in habitat preference.We found that 2 C values had weak phylogenetic signal,whereas the base number of chromosomes(x)had a strong phylogenetic signal.Furthermore,our analyses revealed a positive correlation between genome size and chromosome traits,indicating that the base number of chromosomes(x),chromosome size,and polyploidization may be primary contributors to genome expansion in ferns and lycophytes.Genome sizes in different habitat types varied significantly and were significantly correlated with habitat types;specifically,multinomial logistic regression indicated that species with larger 2 C values were more likely to be epiphytes.Terrestrial habitat is inferred to be ancestral for both extant ferns and lycophytes,whereas transitions to other habitat types occurred as the major clades emerged.Shifts in habitat types appear be followed by periods of genomic stability.Based on these results,we inferred that habitat type changes and multiple whole-genome duplications have contributed to the formation of large genomes of ferns and their allies during their evolutionary history.
文摘Despite that several studies have shown that data derived from species lists generated from distribution occurrence records in the Global Biodiversity Information Facility(GBIF)are not appropriate for those ecological and biogeographic studies that require high sampling completeness,because species lists derived from GBIF are generally very incomplete,Suissa et al.(2021)generated fern species lists based on data with GBIF for 100 km×100 km grid cells across the world,and used the data to determine fern diversity hotspots and species richness-climate relationships.We conduct an evaluation on the completeness of fern species lists derived from GBIF at the grid-cell scale and at a larger spatial scale,and determine whether fern data derived from GBIF are appropriate for studies on the relations of species composition and richness with climatic variables.We show that species sampling completeness of GBIF is low(<40%)for most of the grid cells examined,and such low sampling completeness can substantially bias the investigation of geographic and ecological patterns of species diversity and the identification of diversity hotspots.We conclude that fern species lists derived from GBIF are generally very incomplete across a wide range of spatial scales,and are not appropriate for studies that require data derived from species lists in high completeness.We present a map showing global patterns of fern species diversity based on complete or nearly complete regional fern species lists.
基金Support from projects PAPIIT IN215914 and IV201015
文摘We analyzed the distributional patterns of95 selected species of leptosporangiate ferns inhabiting the Mexican Mountain Component, using grid-cells of one geographical degree as unit areas,applying endemism indices and richness and beta diversity analyses.Distributional data were obtained from several herbaria and specialized literature.Five grid-cells appear to be important for fern species richness, as they contain 35 to 49 species.These gridcells are located in the Sierra Madre Oriental(SMO),Trans-Mexican Volcanic Belt(TMVB) and the Sierra Madre del Sur(SMS).Mean richness by latitudinal belts of one degree showed that the belts with highest values are related to the TMVB and SMS.A total of 13grid-cells were recognized as important from theperspective of endemism; most of them are located also in the SMO, TMVB and SMS.The richest gridcells coincided with one of the main centres of endemism for ferns obtained in this study, located in the convergence of the southern part of the SMO, the eastern portion of the TMVB and the northern part of the SMS, reflecting the high humidity existing on the mountain slopes facing the Gulf of Mexico.Some important grid-cells recognized from richness and endemism analyses coincide with Mexican Natural Protected Areas.The beta diversity analysis showed a low degree of similarity among grid-cells, implying a high species replacement, as the result of environmental heterogeneity occurring in the Mexican mountain systems.On the other hand, the spatial analysis suggested a pattern of phytogeographical regionalization comprising twomain areas: the Mexican Transition Zone and the Mexican Central Plateau.Ferns play an important role in the Mexican biodiversity and contributing to the beta diversity of Mexico.
文摘We documented the status of fern diversity, biomass and car- bon accumulation at Chilapatta Reserve Forest in Cooch Behar Wildlife Division, West Bengal. Stratified random nested quadrat sampling was adopted for analyzing the qualitative and quantitative characters. Nineteen fern species were recorded, of which two are yet to be identified. Identified species were of eight families and nine genera. Highest and lowest frequency recorded were 25.44 and 0.19 while relative frequency varied from 3.16 to 12.25. Fern density ranged from 93 to 13,403 individuals.ha^-1. Most of the species were widely distributed. IVI values ranged from 7.54 to 37.45. The above ground portion of ferns accumulated the major portion ofbiomass and carbon.
文摘Objective: To investigate the antifungal activity of the fern species Lygodium venustum(L. venustum) and Pityrogramma calomelanos(P. calomelanos) against Candida albicans and Candida tropicalis strains.Methods: The microdilution method was used to evaluate the antifungal activity, as well as the modulating effects of ethanolic extracts of these plants in combination with fluconazole. The minimum inhibitory concentration(MIC), minimum fungicide concentration and morphological changes were also determined.Results: The extract obtained from L. venustum presented a MIC > 8 192 mg/m L, while the extract obtained from and P. calomelanos presented a MIC = 8 192 mg/m L, indicating that they present weak antifungal activity. However, combination of the extracts with Fluconazole potentiated the antifungal activity of this drug. At different experimental conditions, such as concentration of the extract and type of strain, the extracts inhibited hyphae and pseudohyphae formation, indicating that these fern species can affect the morphology of the fungi.Conclusions: The extracts obtained from the fern species L. venustum and P. calomelanos dose not present significant antifungal activity. However, P. calomelanos potentiates the activity of fluconazole and both extracts inhibits the morphological changes in Candida species, indicating that they have potential pharmacological activity as modulators of fungal biology. Therefore, novel studies are required to characterize the interference of these extracts in the virulence and pathogenicity of Candida species as well as the potential of fern species to treat fungal infections.
基金Supported by Plant Resources and Floristic Studies of Grassland in Gansu Province(034-036236)Forage Genetic Resources Protection and Germplasm Resource Bank Construction in Guangxi Province(GKN 14123006-32)China Agricultural Industry Research System"Innovation Team Construction for Beef Cattle and Mutton Sheep Industry in Guangxi Province"(nycytxgxcxtd-09-04)
文摘In order to fully understand the distribution characteristics and geographical elements of fern flora and to reveal their process of natural history, the present study analyzed the floristic composition and geographical distribution of ferns in grassland of Gansu Province. The results showed that there were 31 species of ferns in grassland of Gansu, belonging to 19 genera and 14 families. The investigated ferns accounted for 22.22%, 8.26% and 1.99% of total families (63), total genera (230) and total species (2 600) of ferns resources, respectively. The dominant families were Dryopteridceae and Polypodiaceae; the dominant genera were Selaginella and Woodsia. Families mainly belonged to tropical distribution type and genera mainly belonged to tropical and temperate distribution type without endemic genus. Vertical distribution was obvious ; plant components contained old families and genera. The richness of fern in Gansu grassland was not high.
文摘Using a mixed culture of megaspores and microspores from I. coreana, we established high frequency sporophyte regeneration system. After 20 days of culturing in MS basal medium, microscopic examination showed significant morphological changes and the microspore released numerous small vesicles into the culture medium. Megaspores also showed dramatic morphological changes during its incubation time in culture. The spore wall was cracked by the expansion of the megaspore (about 2 times increase in diameter). Simultaneously, brown spots were observed on the surface of the megaspores. The frequency of female gametophytes developing from immature megaspores cultured in MS basal liquid medium (pH 7) supplemented with 1 mgl-1 GA3 was 46%. However, these female gametophytes derived from megaspore only culture could not differentiate into sporophytes. The mixed culture of microspores and megaspores resulted in successful sporophyte regeneration. The highest frequency (12.3%) of green sporophyte regeneration from mixed spore culture occurred when the cultures were maintained at 25℃ under cool-white fluorescent light (40 μmol·m-2·s-1) with a 16 h photoperiod. Regenerated sporophytes were transferred to a test tube containing vermiculite and a sand mixture and left there until they had three leaves. After root growth and the fifth leaf had emerged, more than 95% of the regenerated sporophytes were successfully transferred to the soil and grown to mature plants. The sporophyte regeneration system established in this study could be successfully used for the restoration of the endangered aquatic species, I. coreana.
文摘The present work focuses on the development of a novel computer-based approach for tear ferning(TF)featuring.The original TF images of the recently developedfive-point grading scale have been used to assign a grade for any TF image automatically.A vector characteristic(VC)representing each grade was built using the reference images.A weighted combination between features selected from textures analysis using gray level co-occurrence matrix(GLCM),power spectrum(PS)analysis and linear specificity of the image were used to build the VC of each grade.A total of 14 features from texture analysis were used.PS at di®erent frequency points and number of line segments in each image were also used.Five features from GLCM have shown significant di®erences between the recently developed grading scale images which are:angular second moment at 0and 45,contrast,and correlation at 0and 45;thesefive features were all included in the characteristic vector.Three specific power frequencies were used in the VC because of the discrimination power.Number of line segments was also chosen because of dissimilarities between images.A VC for each grade of TF reference images was constructed and was found to be significantly different from each other's.This is a basic and fundamental step toward an automatic grading for computer-based diagnosis for dry eye.
基金Supported by 2019 Undergraduate Innovation and Enterpreneurship Training Program of Fujian Province(201912631026)Undergraduate Innovation and Enterpreneurship Training Program of Xiamen Medical College(201912631057)。
文摘[Objectives] This study was conducted to optimize the extraction process of luteolin, a natural product of Ternate Grape Fern Herb, so as to provide a theoretical research basis for the chemical composition, pharmacological research and preparation development of Ternate Grape Fern Herb. [Methods] The effects of four factors including ultrasonic extraction time, liquid-to-material ratio, ultrasonic extraction temperature and ethanol concentration on extraction yield of luteolin from Ternate Grape Fern Herb were investigated by the ultrasonic-assisted extraction technology, through a single-factor experiment and an orthogonal experiment based on the single-factor experiment, and the experimental data was subjected to variance analysis and SSR analysis of the significance of differences between groups by SPSS20.0 software to select the optimal extraction process conditions. [Results] The optimal extraction process conditions were as follows: ultrasonic extraction time 25 min, liquid-to-material ratio 25∶1 ml/g, ethanol volume fraction 60%, ultrasonic extraction temperature 85 ℃. [Conclusions] The results were verified, and it was determined that the ultrasonic-assisted extraction process established in this study is reasonable and reliable, and can be used for the extraction of luteolin.
文摘Objective To evaluate the saliva ferning test (SFT) as diagnostic test for xerostomia in patients with Sjogren’s Syndrome (SS). Methods In this study, dried samples of freshly produced saliva from 78 patients with established SS according to European Community criteria and 80 healthy controls were examined by light microscopy. The crystallization was classified into 4 types according to the ferning phenomenon: uniformity, branching, spreading and integrity (type I normal and type Ⅱ,Ⅲ,Ⅳ abnormal ). Then, the 78 patients underwent lebial salivary gland biopsy. According to Tarpley’s classifica- tion, minor salivary gland biopsy (≥2 + ) was considered to be positive . Results 1. The sensitivity of SFT was high (70/ 78 = 89. 74% ). And the specificity wes also high (67/80 = 83. 75% ). 2. Abnormal SFT was observed in 70/78 (89. 74% ) samples from patients group and in 13 /80 (16. 25% ) samples from healthy controls. The differences of SFT in patients group versus controls were statistically significant (P< 0. 01 ). 3. The sensitivity of SFT and mini labial gland biopsy had no significant differences (P > 0. 05) as diagnostic tests in SS. Conclusion SFT was simple, sensitive and specific as diagnostic test in SS suspect patients just as mini labial gland biopsy.
基金The authors thank Dr.Alejandra Vasco,New York Bo-tanical Garden(NYBG),for information on the systema-tics studies in the groupthe National Council for Sci-entific and Technological Development(CNPq)for the Master scholarship of the first author(CNPq 132809/2009-5).
文摘This study describes the anatomy of sterile leaves of Elaphoglossum discolor (Kuhn) C. Chr., E. flaccidum (Fée) T. Moore and E. laminarioides (Bory ex Fée) T. Moore, the most representative species of the genus in the Ecological Park of Gunma in Pará State. It reports the main diagnostic characters and provides new systematic data for the group. In addition, it locates the production and accumulation sites of bioactive compounds to determine possible adaptive strategies of these species in the Amazon rainforest environment. Diagnostic structural features include stoma typology, central veins and margin forms, type of mesophyll, and the presence of schlerenchymatous sheaths in the cortex, among others. Among the bioactive compounds related to defense adaptation are phenolic compounds, which occur in all three species, and alkaloids and mucilage, which are exclusive to E. laminarioides. Of the three species studied, E. laminarioides has features that make it the best suited to the rainforest environment.