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Composition Analysis of Lycophytes and Ferns in Yunzhongshan Nature Reserve, Fujian Province
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作者 Jinquan SHEN Minyong LU +4 位作者 Baohua WU Lingming LIN Jinhuo HE Ying FENG Yinbing XIE 《Plant Diseases and Pests》 2025年第2期34-37,共4页
[Objectives]To analyze the composition of lycophytes and ferns in Yunzhongshan Nature Reserve,Fujian Province.[Methods]This study examined the composition of lycophytes and ferns in Yunzhongshan Nature Reserve through... [Objectives]To analyze the composition of lycophytes and ferns in Yunzhongshan Nature Reserve,Fujian Province.[Methods]This study examined the composition of lycophytes and ferns in Yunzhongshan Nature Reserve through field investigations and specimen identification,supplemented by a review of relevant literature.[Results]A total of 84 species of lycophytes and ferns were identified,encompassing 55 genera and 29 families.This included 14 species of lycophytes distributed across 8 genera and 3 families,as well as 70 species of ferns belonging to 47 genera and 26 families.Polypodiaceae and Selaginella were the dominant family and genus,respectively,while oligospecific families and monotypic genera were significant components of lycophytes and ferns in the region.The distribution types of these families were primarily cosmopolitan and tropical.The Germline differentiation degree(SD)was 3.34,and the proportion of rare or endangered species among lycophytes and ferns was 8.33%.[Conclusions]Yunzhongshan Nature Reserve possesses a diverse array of lycophyte and fern species.This study offers valuable scientific insights that can inform efforts related to the conservation of biodiversity,resource utilization and development,species introduction,and system evolution of lycophytes and ferns within the reserve. 展开更多
关键词 NATURE RESERVE LYCOPHYTES ferns COMPOSITION
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The Indo-Burma biodiversity hotspot for ferns:Updated phylogeny,hidden diversity,and biogeography of the java fern genus Leptochilus(Polypodiaceae)
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作者 Liang Zhang Zhen-Long Liang +4 位作者 Xue-Ping Fan Ngan Thi Lu Xin-Mao Zhou Hong-Jin Wei Li-Bing Zhang 《Plant Diversity》 SCIE CAS CSCD 2024年第6期698-712,共15页
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
关键词 Cryptic speciation Dispersals from lower to higher latitudes Nuclear pgiC gene Fern diversity hotspot Java ferns Microsoroids
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Resources of Wild Ornamental Ferns in Guizhou Province and Their Utilization 被引量:1
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作者 杨碧仙 赵俊华 +2 位作者 潘炉台 赵能武 云雪林 《Journal of Landscape Research》 2010年第1期80-83,94,共5页
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
关键词 ORNAMENTAL ferns GUIZHOU Province GARDEN GREENING application
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Prediction of Suitable Habitat for Lycophytes and Ferns in Northeast China: A Case Study on Athyrium brevifrons 被引量:4
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作者 LI Yan CAO Wei +2 位作者 HE Xingyuan CHEN Wei XU Sheng 《Chinese Geographical Science》 SCIE CSCD 2019年第6期1011-1023,共13页
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
关键词 Athyrium brevifrons LYCOPHYTES and ferns MAXENT suitable HABITAT Northeast China GAMETOPHYTE
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Genome size evolution of the extant lycophytes and ferns 被引量:3
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作者 Fa-Guo Wang Ai-Hua Wang +14 位作者 Cheng-Ke Bai Dong-Mei Jin Li-Yun Nie AJ Harris Le Che Juan-JuanWang Shi-Yu Li Lei Xu Hui Shen Yu-Feng Gu Hui Shang Lei Duan Xian-Chun Zhang Hong-Feng Chen Yue-Hong Yan 《Plant Diversity》 SCIE CAS CSCD 2022年第2期141-152,共12页
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
关键词 Genome size ferns Chromosome numbers Habitat type Whole-genome duplications EVOLUTION
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Diversity, Endemism and Conservation of Ferns(Polypodiales) in the Mexican Mountain Component 被引量:2
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作者 SANGINéS-FRANCO Celia LUNA-VEGA Isolda +3 位作者 CONTRERAS-MEDINA Raúl ESPINOSA David TEJERO-DíEZ José Daniel RIVAS Gerardo 《Journal of Mountain Science》 SCIE CSCD 2015年第4期891-904,共14页
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
关键词 BIOGEOGRAPHY Distributional patterns Leptosporangiate ferns Mexico
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Chemical constituents and biological activities of lycophytes and ferns 被引量:1
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作者 ZHU Qin-Feng ZHAO Qin-Shi 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2019年第12期887-891,共5页
Lycophytes and ferns are unique and charismatic members of many terrestrial ecosystems and occupy the pivotal position in land plant origin and evolution.The Chinese lycophytes and ferns flora,with approximately 2000 ... Lycophytes and ferns are unique and charismatic members of many terrestrial ecosystems and occupy the pivotal position in land plant origin and evolution.The Chinese lycophytes and ferns flora,with approximately 2000 species,contributes a substantial component to the global lycophytes and ferns diversity,with estimates of 12000 species.Among them,about 433 species are medicinally recorded and researches based on their phytochemical properties are important topics in natural medicines.This paper reviewed the research history and current status of chemical constituents and biological activities of lycophytes and ferns,which had highlighted the research progress of our group. 展开更多
关键词 LYCOPHYTES ferns Chemical constituents Biological activities Lycopodium alkaloids
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Resource Distribution and Exploitation of Edible Ferns in Guizhou
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作者 云雪林 赵能武 +1 位作者 潘炉台 赵俊华 《Agricultural Science & Technology》 CAS 2009年第5期102-106,139,共6页
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
关键词 GUIZHOU Edible fern Resource distribution
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Evaluation of transgenic cotton lines expressing an insecticidal fern protein against whitefly,Bemisia tabaci(Gennadius)
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作者 KUMAR Rishi NAGRARE V.S. +14 位作者 SHAH Vivek SINGH Satnam PANDHER Suneet SINGH Satpal VERMA S.K. PAUL Debashis RATHORE Pankaj SHUKLA Anoop Kumar SINGH Mithlesh Kumar SAURABH Sharad KUMAR Harish KAUR Rupinderjeet SINGH Pradhyumna Kumar WAGHMARE V.N. PRASAD Y.G. 《Journal of Cotton Research》 2025年第2期163-177,共15页
Background Transgenic research in crops involves using genetic engineering techniques to introduce specific genes of interest from other organisms,or even entirely new genes into plant genomes to create crops with des... Background Transgenic research in crops involves using genetic engineering techniques to introduce specific genes of interest from other organisms,or even entirely new genes into plant genomes to create crops with desirable traits that wouldn’t be possible through conventional breeding methods.Transgenic crops have been developed for various traits globally.Whitefly,Bemisia tabaci(Gennadius)is one of the major sucking pests of cotton that cause significant damage to the cotton production.To combat whitefly infestations,researchers have developed four transgenic cotton lines expressing the fern protein.And those transgenic lines need to be evaluated for their performance against the target pest—whitefly.The evaluation was designed as controlled trials in polyhouse or muslin cloth cages under open-choice and no-choice conditions by comparing four transgenic cotton lines(A,B,C,and D)with three control groups,including untransformed cotton plants with a same genetic background of the transgenic line,conventionally bred whitefly-resistant cotton,and whitefly-susceptible cotton.In order to study the generational effect,the evaluation also involved studies on whitefly development in laboratory,muslin cloth cage,and polyhouse conditions.Results Both open-choice and no-choice experiments had shown that all the four transgenic cotton lines(A,B,C,and D)expressing the fern protein reduced adult whitefly numbers significantly compared with the control lines,except for the no-choice conditions in 2021,where the transgenic line C was non-significant different from the resistant control line.Notably,the nymphal population on the resistant control line was relatively low and nonsignificant different from the transgenic line C in 2021;and the transgenic lines A and C in 2022 under open-choice conditions.Under no-choice condition,the nymphal counts in the resistant control line was non-significant different from transgenic lines C and D in 2021;and transgenic line D in 2022.All transgenic lines showed significant decrease in egg hatching in 2021 and nymphal development in 2022,except for the transgenic line C which had no significant different in the nymphal development comparing with non-transgenic control lines in 2022.Adult emergence rates in both years of evaluation showed significant decrease in transgenic lines A and B comparing with the control lines.Additionally,the results showed a significant reduction in cotton leaf curl disease and sooty mold development in all the four transgenic lines compared with susceptible control under open-choice conditions,indicating potential benefits of transgenic lines beyond direct effect on whitefly control.Furthermore,the research explored the generational effects of the fern protein on whitefly which revealed the lowest fecundity in the transgenic line C across F0,F1 and F3 generations,lower egg hatching in F1 and F2 generations in transgenic lines A and B,shorter nymphal duration in F1 and F2 generations in transgenic line B,and the least total adult emergence in the transgenic line C in F0 and F3 generations.Conclusions These findings suggest that the transgenic cotton lines expressing fern protein disrupts whitefly populations and the life cycle to a certain extent.However,results are not consistent over generations and years of study,indicating these transgenic lines were not superior over control lines and need to be improved in future breeding. 展开更多
关键词 EVALUATION Fern protein Transgenic cotton lines WHITEFLY
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Joint inversion of body wave arrival times and surface wave dispersion data for the subduction zone velocity structure of central Chile
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作者 ZiXin Chen HaiJiang Zhang +3 位作者 Lei Gao Ying Liu ShaoBo Yang Diana Comte 《Earth and Planetary Physics》 2025年第5期1048-1060,共13页
The Chilean Pampean flat slab subduction segment is characterized by the nearly horizontal subduction of the Nazca Plate within the depth range of 100-120 km.Numerous seismic tomography studies have been conducted to ... The Chilean Pampean flat slab subduction segment is characterized by the nearly horizontal subduction of the Nazca Plate within the depth range of 100-120 km.Numerous seismic tomography studies have been conducted to investigate its velocity structure;however,they have used only seismic body wave data or surface wave data.As a result,the existing velocity models in the region may have relatively large uncertainties.In this study,we use body wave arrival times from earthquakes occurring in central Chile between 2014 and 2019,as well as Rayleigh wave phase velocity maps at periods of 5-80 s from ambient noise empirical Green’s functions in Chile.By jointly using body wave arrival times and surface wave dispersion data,we refine the VS model and improve earthquake locations in the central Chile subduction zone.Compared with previous velocity models,our velocity model better reveals an eastward-dipping high-velocity plate representing the subducting Nazca Plate,which is 40-50 km thick and is more consistent with the slab thickness estimated by receiver function imaging and thermal modeling.Overall,the intraslab seismicity distribution spatially correlates well with the slab high-velocity anomalies except along the subduction paths of the CopiapóRidge and Juan Fernández Ridge.Additionally,parallel low-velocity stripes are imaged beneath the subducting plate,which are likely associated with the accumulated melts.The joint inversion velocity model also resolves widespread low-velocity anomalies in the crust beneath the Central Volcanic Zone of the central Andes,likely representing crustal magma chambers for various volcanoes. 展开更多
关键词 Chilean Pampean flat slab seismic joint inversion seismic velocity model Central Volcanic Zone of the central Andes CopiapóRidge Juan Fernández Ridge
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基于多分类的虹膜匹配方法
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作者 代刚 张海滨 《无线电工程》 2013年第11期60-64,共5页
在传统的虹膜识别系统中,虹膜匹配被认为是一个二分类问题:类内匹配和类间匹配。许多已存在的方法简单地利用距离来执行虹膜匹配。由于这些方法不能很好地利用虹膜特征,所以会产生很高的拒识率和误识率,且鲁棒性不强。为了解决这些问题... 在传统的虹膜识别系统中,虹膜匹配被认为是一个二分类问题:类内匹配和类间匹配。许多已存在的方法简单地利用距离来执行虹膜匹配。由于这些方法不能很好地利用虹膜特征,所以会产生很高的拒识率和误识率,且鲁棒性不强。为了解决这些问题,提出把虹膜匹配当作一个多分类问题,采用一种新颖的蕨算法(Ferns)分类器来完成该工作。相比支持向量机(SVM)分类器,在执行虹膜匹配时,Ferns分类器有诸多优点。为了对提出的算法给出全面评价,实验中分别在认证和识别这2种模式下对该算法进行测试。实验结果证明,提出的方法可以极大地改善虹膜识别系统的性能。 展开更多
关键词 虹膜识别 ferns分类器 SVM 虹膜匹配 接受器工作特性(ROC)曲线
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融合多重Bayesian决策的多视角视频车辆快速检索算法 被引量:3
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作者 鲁建飞 谢振平 刘渊 《小型微型计算机系统》 CSCD 北大核心 2015年第5期1122-1126,共5页
从图像特征点匹配的角度出发,提出一种融合多重Bayesian决策的多视角视频车辆快速检索算法.算法基于随机Ferns特征,对目标车辆的多视角图片进行特征点提取,融合多视角图片特征点进行特征训练,构建双层贝叶斯分类器,融合两重Bayesian决... 从图像特征点匹配的角度出发,提出一种融合多重Bayesian决策的多视角视频车辆快速检索算法.算法基于随机Ferns特征,对目标车辆的多视角图片进行特征点提取,融合多视角图片特征点进行特征训练,构建双层贝叶斯分类器,融合两重Bayesian决策计算视频图像中检测出的特征点集的联合概率,为当前视频图像分配类标签,完成多视角视频车辆的快速检索.对比试验表明,该算法与其他利用图像匹配算法进行视频检索的方法相比具有较高的识别率和较低的时间复杂度,并具备一定的实际使用价值. 展开更多
关键词 视频检索 随机ferns 贝叶斯决策 多视角
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