Cainozoic ferns and their distribution

The phytogeographic distribution of Cainozoic ferns is reported based upon a critical re-appraisal of the macrofossil and mesofossil record also taking account of evidence from a few highly diagnostic spores. Well-documented circum-Arctic Cainozoic floras show ferns (Woodwardia, Onoclea, Osmunda, Coniopteris and to a lesser extentAzolla) distributed around the pole to very high paleolatitudes. Some ferns are shared between the mid-paleolatitudes of North America and Europe as would be predicted from the distributions of other biota. Evidence for the composition of Cainozoic fern floras is minimal in some regions (e.g., Antarctica, Central and South America, Africa, India, South East Asia), so the absence of fern fossils from these areas has no biogeographical significance. Matoniaceae were abundant in the preceding Mesozoic. However, the absence of Cainozoic macrofossils, and the fact that no CainozoicMatonisporites spores areMatonia-like, indicates that Matoniaceae had attained their modern relict distribution by, or very early in, the Cainozoic. The important Mesozoic families Marattiaceae and Dipteridaceae are also not represented by Cainozoic macrofossils. They probably also showed Cainozoic restriction but spores are not sufficiently diagnostic to enable testing of this hypothesis. Other ferns, which were also important in the Mesozoic (e.g., Dicksoniaceae, Gleicheniaceae), have patchy, equivocal, or inadequately published Cainozoic records. The dispersed spore record may provide an opportunity to track Cainozoic Gleicheniaceae but this approach is not without problems. Most well-represented Cainozoic fern families, genera and subgenera show widespread Cainozoic ranges, typically with considerable range extensions over their living relatives, both onto other continents and north and south to higher paleolatitudes. These include Schizaeaceae (Lygodium, Anemia, and the extinctRuffordia), Osmundaceae (Osmunda), Pteridaceae (Acrostichum), Thelypteridaceae (Cyclosorus), Lophosoriaceae (Lophosoria), Cyatheaceae (theCnemidaria/Cyathea decurrens clade) and the heterosporous water fernAzolla (Azollaceae). A few well-represented ferns show Cainozoic distributions similar to those of the present day (e.g.,Salvinia [Salviniaceae] andCeratopteris [Pteridaceae] (the latter by the Neogene and based only on spores]) but even these had slightly broader ranges in the Cainozoic. Some Cainozoic ferns have apparently local distributions, e.g.,Blechnum dentatum (Blechnaceae) in Europe; and others are so far represented at only one or few sites, e.g.,Dennstaedtiopsis (Dennstaedtiaceae),Botrychium (Ophioglossales),Grammitis (Grammitidaceae), andMakotopteris andRumohra (Dryopteridaceae). Cainozoic fossils assigned toDryopteris (and some other dryopteroids) require revision along with those of Thelypteridaceae, the latter having high potential to provide useful paleobiogeographic evidence, at least of theCyclosorus group. Cainozoic records of Hymenophyllaceae and Polypodiaceae are here considered unconfirmed.     

上海市蕨类植物分布特点及其与环境因子关系分析

在查阅资料和标本基础上,对上海市33个样地蕨类植物进行了野外调查,初步确定了上海市自然分布的蕨类植物23科31属50种,并讨论了归化种与栽培种及曾有记录而可能消亡的种类。采用双向指示种法（TWINSPAN）和典范对应分析（CCA）方法对蕨类植物分布特点及其与环境因子关系进行了分析。结果表明：（1）蕨类分布的样点可分为3组,第1组为市区样点,种数为0～4种;第2组为市郊样点,种数为0～8种;第3组为佘山岛、佘山地区、大金山岛,是上海蕨类最丰富地区,种数达26种以上。（2）影响上海蕨类植物生长的主要环境因子为基质、郁闭度和人为干扰。     

中国石松类和蕨类植物的多样性与地理分布

物种编目及其科属系统排列是了解生物多样性的基础, 本文采用Flora of China使用的分类系统, 结合最新分子分类学研究成果以及近几年发表的新资料, 对中国石松类和蕨类植物多样性和地理分布数据进行了统计和分析。结果表明中国共有石松类和蕨类植物40科178属2,147种5个亚种118个变种, 其中特有种839个, 占总种数的39.08%。种数最多的5个科依次为鳞毛蕨科(505种, 含种下单位, 下同)、蹄盖蕨科(323种)、水龙骨科(280种)、凤尾蕨科(266种)和金星蕨科(209种); 种数最多的5个属依次为耳蕨属(Polystichum, 209种)、鳞毛蕨属(Dryopteris, 176种)、蹄盖蕨属(Athyrium, 137种)、双盖蕨属(Diplazium, 98种)和凤尾蕨属(Pteris, 97种)。在地理分布上, 种数排名前5的省份为云南(1,365种)、四川(875种)、贵州(838种)、广西(785种)和台湾(779种)。含中国特有石松类和蕨类植物的科属中, 排前3位的科分别为鳞毛蕨科(257种)、蹄盖蕨科(169种)和凤尾蕨科(113种); 排前3位的属为耳蕨属(140种)、蹄盖蕨属(82种)和鳞毛蕨属(61种)。     

黄土高原石松类和蕨类植物的多样性与地理分布

物种编目是了解生物多样性的基础。本文收集已出版的专著和文献, 查阅标本馆的馆藏标本信息, 在此基础上, 对黄土高原的石松类和蕨类植物的多样性和地理分布数据进行统计和分析。科属排列采用Flora of China的分类系统, 科属界定依据分子系统学的最新研究成果。结果表明, 黄土高原共有石松类和蕨类植物18科42属165种2亚种5变种, 其中中国特有种35种, 占总种数的20.35%。种类数量最多的5个科依次为凤尾蕨科(29种, 含种下单位, 下同)、鳞毛蕨科(28种)、水龙骨科(19种)、蹄盖蕨科(16种)和铁角蕨科(16种); 种类数量最多的6个属依次为铁角蕨属(Asplenium, 16种)、鳞毛蕨属(Dryopteris, 15种)、耳蕨属(Polystichum, 12种)、岩蕨属(Woodsia, 11种)、卷柏属(Selaginella, 10种)和瓦韦属(Lepisorus, 10种)。黄土高原的石松类和蕨类植物中, 无珍稀濒危保护植物, 无中国特有属。依据生态类型可划分为4类, 即土生植物(112种)、石生植物(75种)、附生植物(18种)、水生植物(3种), 该区域石松类和蕨类植物土生或石生的种类占总种数的89.53%。在地理分布上, 黄土高原石松类和蕨类处于我国现生类群分布的边缘区域, 这与我国的石松类和蕨类分布规律基本一致。     

Chicoric acid ameliorate inflammation and oxidative stress in Lipopolysaccharide and d-galactosamine induced acute liver injury

Chicoric acid is polyphenol of natural plant and has a variety of bioactivity. Caused by various kinds of stimulating factors, acute liver injury has high fatality rate. The effect of chicoric acid in acute liver injury induced by Lipopolysaccharide (LPS) and d -galactosamine (d -GalN) was investigated in this study. The results showed that CA decreased the aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in serum and reduced the mortality induced by LPS/d -GalN. CA can restrain mitogen-activated protein kinases (MAPKs) and nuclear factor-kappa B (NF-κB) to alleviate inflammation. Meanwhile, the results indicated CA can active nuclear factor-erythroid 2-related factor 2 (Nrf2) pathway with increasing the level of AMP-activated protein kinase (AMPK). And with the treatment of CA, protein levels of autophagy genes were obvious improved. The results of experiments indicate that CA has protective effect in liver injury, and the activation of AMPK and autophagy may make sense.     

贡嘎山石松类和蕨类植物的多样性与海拔分布（附表）

贡嘎山是横断山脉海拔最高的一座大山,是研究山地植物多样性和海拔分布的理想地区。为了探讨贡嘎山地区石松类和蕨类植物多样性组成及海拔分布特点,该研究基于野外考察、标本采集鉴定及文献考证,对贡嘎山地区石松类和蕨类植物进行统计和分析。结果表明:(1)贡嘎山地区有石松类植物3科4属25种,蕨类植物有23科56属291种。(2)主要的珍稀濒危植物有6种,分别是高寒水韭(Iso tes hypsophila)、松叶蕨(Psilotum nudum)、桫椤(Alsophila spinulosa)、小叶中国蕨(Aleuritopteris albofusca)、玉龙蕨(Polystichum glaciale)和扇蕨(Lepisorus palmatopedatus)。(3)优势科为鳞毛蕨科(Dryopteridaceae)75种、水龙骨科(Polypodiaceae)56种、凤尾蕨科(Pteridaceae)54种和蹄盖蕨科(Athyriaceae)37种;优势属为耳蕨属(Polystichum)45种、鳞毛蕨属(Dryopteris)24种、蹄盖蕨属(Athyrium)24种和瓦韦属(Lepisorus)19种。(4)区系以温带成分为主,有286种(93.77%)。随着海拔的上升,石松类和蕨类的物种多样性逐渐增加,2000~3000 m海拔段的物种多样性最高,为20科46属192种,3000 m以上物种多样性逐渐下降,4500 m以上仅分布有4种蕨类植物。此外,该研究还发现,随着海拔的升高,中国-喜马拉雅成分逐渐增加。     

Chicoric acid, a new compound able to enhance insulin release and glucose uptake

Caffeic acid and chlorogenic acid (CGA), a mono-caffeoyl ester, have been described as potential antidiabetic agents. Using in vitro studies, we report the effects of a dicaffeoyl ester, chicoric acid (CRA) purified from Cichorium intybus, on glucose uptake and insulin secretion. Our results show that CRA and CGA increased glucose uptake in L6 muscular cells, an effect only observed in the presence of stimulating concentrations of insulin. Moreover, we found that both CRA and CGA were able to stimulate insulin secretion from the INS-1E insulin-secreting cell line and rat islets of Langerhans. In the later case, the effect of CRA is only observed in the presence of subnormal glucose levels. Patch clamps studies show that the mechanism of CRA and CGA was different from that of sulfonylureas, as they did not close K_ATP channels. Chicoric acid is a new potential antidiabetic agent carrying both insulin sensitizing and insulin-secreting properties.     

Chicoric and Chlorogenic Acids in Plant Species from Georgia

Chicoric acid was isolated from dandelion (Taraxacum officinaleWigg.) leaves by column chromatography. Conditions for HPLC analysis of chicoric and chlorogenic acids were optimized. These acids were assayed in some plants growing in Georgia. The optimum conservation temperature for the preservation of chicoric and chlorogenic acids in the leaves of dandelion and bilberry (Vaccinium arctostaphylosL.) was determined.     

Chicoric and chlorogenic acids in various plants growing in Georgia

Chicoric acid was isolated from dandelion (Taraxacum officinale Wigg.) leaves by column chromatography. Conditions for HPLC analysis of chicoric and chlorogenic acids were optimized. These acids were assayed in some plants growing in Georgia. The optimum conservation temperature for the preservation of chicoric and chlorogenic acids in leaves of dandelion and bilberry (Vaccinium arctostaphylos L.) was determined.     

Diversity and distribution of ferns in sub-Saharan Africa, Madagascar and some islands of the South Atlantic

Aim This paper reports the diversity and endemism patterns of African ferns, and explores the potential role of diversity refuges and environmental and historical factors in the shaping of these patterns. Material and locations The extant fern taxa occupying Africa south of the Sahara, Madagascar and some islands of the South Atlantic. Methods The number of taxa in each area or operational geographical unit (OGU) was scored, and the correlation between this number and physical and climatic variables analysed by standard pairwise and stepwise multiple regression analysis (SPR and SMR). The effects of biological factors such as dispersal capacity, reproductive biology, genetic features and certain physiological adaptations were evaluated by comparing the number of species in each OGU. Floral affinities among OGUs were analysed using non‐metric multi‐dimensional scaling (NMS) and parsimonic analysis of dispersion (PAD), and compared with β‐turnover and inter‐OGU distances. Results OGU area, elevation and the distance between refuges determined the composition of local floras, but only greater OGU area and the existence of higher maximum elevations increased species richness. The distance between refuges also affected the number of endemic species, especially on islands. The biological features studied only slightly influenced fern distribution. The main climatic predictor of species number was humidity. SPR and SMR revealed three main groups of ferns with different ecological trends. NMS and PAD analyses separated the four areas of highest diversity in Africa, three of which are inhabited by ferns with distinct ecological requirements. The fourth area was Madagascar, which shows an accumulation of endemic and relict diversity that is not easy to explain. Main conclusions The distribution of ferns in Africa has been influenced by refuges. These probably allowed many species to recolonize the neighbouring areas after the extinctions of the Pleistocene. Three major components were detected in the African flora: Guinea‐Congolian thermophilous, cold‐tolerant Afro‐montane, and Southern drought‐tolerant elements. These are related to the three main refuge areas, i.e. the Gulf of Guinea area, the eastern tropical region, and the Cape region. Endemicity in ferns was found to be lower than that of seed plants due to the higher dispersability of fern spores. The distance between OGUs seems to be the main predictor of the number of endemic fern species these areas contain.     

The reproductive biology of the invasive ferns Lygodium microphyllum and L. japonicum (Schizaeaceae): implications for invasive potential

The effect of culture system and population source on sexual expression and sporophyte production was examined for two invasive fern species in Florida, USA, Lygodium microphyllum and L. japonicum (Schizaeaceae). Both species are currently spreading through Florida. Long-distance dispersal of ferns is thought to rely on successful intragametophytic selfing. Given the rate of spread observed in both Lygodium species, we hypothesized that both species are capable of intragametophytic selfing. To test this hypothesis, gametophytes of both species were grown in vitro as isolates, pairs, and groups. Both species were capable of intragametophytic selfing; 78% of L. microphyllum isolates produced sporophytes and over 90% of the L. japonicum isolates produced sporophytes. Lygodium microphyllum also displayed the ability to reproduce via intergametophytic crossing, facilitated by an antheridiogen pheromone. Sporophyte production was rapid across mating systems for both species, an advantage in Florida's wet and dry seasonal cycles. The high intragametophytic selfing rate achieved by both species has likely facilitated their ability to colonize and spread through Florida. The mixed mating system observed in L. microphyllum appears to give this species the ability to invade distant habitats and then adapt to local conditions.     

Polar distribution of annexin-like proteins during phytochrome-mediated initiation and growth of rhizoids in the ferns Dryopteris and Anemia

Although the calcium requirement of phytochrome-mediated fern spore germination and early rhizoid growth is well established, the calcium-binding proteins that serve as transducers for these responses are not known. Here we report the presence of annexin-like proteins in germinating spores of Dryopteris filix-mas (L.) Schott and Anemia phyllitidis (L.) Sw. and evidence that they may be important participants in early photomorphogenic changes in gametophytes. Immunolocalization and immunoblot assays of these proteins were carried out using polyclonal antibodies raised either against a 35-kDa annexin-like protein from pea or against anchorin CII from chicken. Western-blot analysis showed that crude protein extracts obtained from both species after red-light treatment contained two cross-reactive protein bands with molecular weights around 70 kDa. These proteins were annexin-like in that they bound to a phosphatidylserine affinity column in a calcium-dependent fashion. Using this column, two protein bands around 70 kDa, i.e. 67 and 73 kDa, were partially purified together with proteins at 36 kDa and a doublet at 54 kDa. Proteins of these latter molecular weights are suggested to be members of the annexin family, but no cross-reactivity could be found between these and the two antibodies used in our investigations. Immunodetectable levels of these proteins were observed only after light-mediated induction of spore germination. Imaging of the immuno-localization patterns observed with both antibodies showed that the annexin-like proteins are concentrated at the extreme tips of the rhizoids in D. filix-mas and A. phyllitidis during rhizoid initiation and all stages of elongation. We suggest that these proteins may play a major role in the tip-oriented exocytosis events that are critical for the initiation and growth of fern rhizoids.Abbreviations CLSM confocal laser scanning microscopy - R red light Dedicated to Professor Andreas Sievers on the occasion of his retirementWe gratefully acknowledge the interest shown by Drs. D.-P. Häder (Botanisches Institut I, Erlangen, Germany) and M. Cresti (Dipartimento di Biologia Ambientale, Siena, Italy), and their generous provision of laboratory facilities. The authors thank Mrs. H. Klappstein and Mr. M. Becker for the careful preparation of the figures. This research was supported by a NATO collaboration grant (CRG 920082) to R. Scheuerlein and by a NASA grant (NAGW 1519) to S.J. Roux.     

Antheridial dehiscence in ferns

We investigated the mechanism of antheridial dehiscence in ferns for the first time using fluorescence microscopy as well as scanning and transmission electron microscopy. The mechanism leading to antheridial dehiscence in Polystichum setiferum, Asplenium trichomanes and A. onopteris was found to depend on the different cellulose contents of the inner and outer walls of the ring cells detected with calcofluor white stain and the Thiéry test. The extremely low cellulose content of the ring cell walls facing spermatozoids made them less mechanically resilient than external wall cells. When the ring cells absorbed water they expanded only into the antheridial cavity, pushing the gametes against the cap cell, which detached from the ring cell below and enabled spermatozoid release. The newly released spermatozoids were spherical bodies covered in cellulose fibrils. The significance of cellulose fibrils could be to isolate the gametes from each other, to reinforce the electron transparent material and to protect the gamete from pressure created by the ring cells during release.     

Correlation between water relations and within-canopy distribution of epiphytic ferns in a Mexican cloud forest

The physiological traits associated with water relations of eight common epiphytic ferns in a Mexican cloud forest were investigated in relation to the distribution of these species within the canopy. Fern distribution was significantly correlated with the relative water content at which stomata close, leaf thickness, stomatal density and size. Trichomanes bucinatum desiccated completely within hours in moderately dry air and was confined to the stem bases, and Asplenium cuspidatum, with no evident adaptations to cope with drought, grew in the second most shaded zone within the tree crowns. Despite growing in a humid cloud forest, all other species had xeric adaptations including coriaceous leaves (Pleopeltis mexicana, Elaphoglossum glaucum), succulent rhizomes (Polypodium puberulum, Phlebodium areolatum), low rates of uncontrolled water loss (all species except P. puberulum), leaf scales (Elaphoglossum petiolatum, Polypodium plebeium), and high cell wall elasticity (all species). P. plebeium and Pl. mexicanum, which grow in the most exposed locations, tolerated water loss beyond the turgor loss point before the stomata closed and appear to be poikilohydric or at least to tolerate high water deficits. Received: 8 June 1997 / Accepted: 30 November 1997