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High-resolution patterns of palaeoenvironmental changes during the Little Ice Age and the Medieval Climate Anomaly in the northwestern Iberian Peninsula

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Geoscience Frontiers 2020年第5期11卷 1461-1475页

作者： Daniel Castro Martin Souto Maria Isabel Fraga Eduardo Garcia-Rodeja Sebastian Perez-Diaz Jose Antonio Lopez Saez Xabier Pontevedra-Pombal dpto.botanica Fac.BioloxiaUniversidade de Santiago de CompostelaGaliciaSpain dpto.Edafoloxia e Quimica Agricola Fac.BioloxiaUniversidade de Santiago de CompostelaGaliciaSpain dpto.Geografia Urbanismo y Ordenacion Del TerritorioETS CaminosCanales y PuertosUniversidad de CantabriaSpain GI Arqueobiologia Instituto de HistoriaCCHS–CSICMadridSpain

to identify plant macrofossils,estimate peat humification and calculate hydroclimatic indices based on current bog species,with the overall aim of determining the climate conditions associated with evolution of the bog during the Medieval Climate Anomaly and the Little Ice Age.These proxies,together with historical and climate data,proved to be good indicators of the changes in bog surface wetness.Analysis:of the core led to identification of 9 different periods:two corresponding to the so-called Medieval Climate Anomaly(930 to 1345 AD,1075–665 calibrated years before present[cal.yr BP]);four corresponding to the Little Ice Age(1345 to 1905 AD;665–105 cal yr BP);and three corresponding to the last century(1905 to 2000 AD).The findings revealed a generally dry climate that lasted until the 14th century,followed by a transition to a long period with a more humid,but characteristically very variable climate,which ended at the beginning of the 20th century and was followed by a rapid transition to more humid conditions and finally,a change to drier conditions.The Medieval Climate Anomaly was indicated by the abundance of dry-adapted mosses(Leucobryum glaucum,Hypnum cupressiforme)and characterized by warm dry conditions and high levels of peat humification,with alternating wet phases.The LIA period was dated by a large abundance of Sphagnum species(an indicator of wetness)and a gradual increase in the humification index.However,four different climate phases were differentiated in this period.High-resolution reconstruction of the evolution of the CVM bog and the multiproxy approach have together enabled a more detailed identification of climatic variations in this area,which are generally consistent with the global models,as well as better definition of the elusive climatic oscillations in the last millennium and confirmation of the importance of local modulation of global models.The study provides new information and a detailed chronology of climatic events that will help to refine local modulation of the climate evol

关键词： Last millennium Raised bog Plant macrofossil Humification analysis Southwest Europe Climate change

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Protein Shuttle between Nucleus and Cytoplasm:New Paradigms in the ABI5-dependent ABA Responses

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Molecular Plant 2019年第11期12卷 1425-1427页

作者： Inmaculada Sanchez-Vicente Pablo Albertos Oscar Lorenzo dpto.de botanica y Fisiologia Vegetal Instituto Hispano-Luso de Investigaciones Agrarias(CIALE)Facultad de BiologiaUniversidad de SalamancaC/Rio Duero 1237185 SalamancaSpain Present address:Biotechnology in Horticultural Crops TU Munchen-WeihenstephanLiesel-Beckmann-Strasse 185354 FreisingGermany

Plant survival depends on seed germination,progression through post-germinative developmental checkpoints,and adaptation to abiotic stresses.All these processes underlie a tightly controlled regulation by the stress hormone abscisic acid(ABA)at different levels,even though the main research focuses on changes in transcript and protein abundance.Nevertheless,protein fate undergoes complex readjustments that allow signal transduction to be integrated into physiological responses.Among them,protein redox status,stability,capacity of oligomerization,formation of complexes,and subcellular compartmentalization become key points for plant reprogramming against stresses to acquire an optimal development.In this Spotlight,we highlight and discuss the latest advances in dissecting the mechanisms driving protein dynamics of nucleocytoplasmic trafficking in the cell and its relevance for regulating the stability of ABI5 and the ABI5-dependent AB A signaling pathway(Figure 1).

关键词： Figure driving programming

Morpho-Anatomy of the Echium plantagineum L. (Boraginaceae) Diaspores in Relation with Water Uptake and Germination

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Phyton-International Journal of Experimental Botany 2020年第2期89卷 345-360页

作者： Maria Laura Molinelli Rocio Tarifa Patricia Perisse Catedra de botanica Morfologica Facultad de Ciencias AgropecuariasUniversidad Nacional de CordobaCordobaArgentina

Echium plantagineum(Boraginaceae)is native of the Mediterranean regions,has been introduced and become widespread within the American continent(North to South),South Africa,New Zealand and Australia.This plant has seed dormancy,aggressively spreads to infest vast areas of predominantly agricultural land and is considered a toxic weed to livestock.The objectives of this research were:(i)to study the morpho-anatomy of the diaspores of E.plantagineum;(ii)to identify the pathway of water uptake;and(iii)to characterize the germination and the seedling.The morpho-anatomical studies were carried out analyzing semi-permanent slides of transverse and longitudinal sections of the fruits,seeds and seedlings.Histological,histochemical and conventional staining techniques by using stereoscopic,optical and scanning electron microscopy were applied.In the diaspores,the water uptake pathway was determined by fast green staining,germination tests were performed and the morpho-anatomy of seedlings was analyzed.The diaspores showed acrescent calyx surrounding the fruit,composed by 4 rough tuberculate mericarpids.Each indehiscent mericarpid encloses an exalbuminous seed with a thin coat and a spatulate embryo with folded coty-ledons.Water uptake took place through the vascular trace“protuberance”in the cicatrix of the mericarpid,which triggers the germination process.Germination was epigeal,the cotyledons were photosynthetically active at the emergence,and a rudimentary developed gemmula was observed.Germination percentage was 66.5%.The macrosclereids of the pericarp functions as an obstacle to water uptake,which is overcome when the mericarpid is detached from the gynobase,and the protuberance that acts as a water uptake path is exposed,leading to germination.The morpho-anatomical characteristics of diaspore,explain the successful dispersal for this aggressive weed,and provide important information in relation to the necessary care for its control.

关键词： Echiumplantagineum fruit germination imbibition mericarpid seed

Review of plant biogeographic studies in Brazil

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Journal of Systematics and Evolution 2009年第5期47卷 477-496页

作者： Pedro FIASCHI José R.PIRANI Department of Biology Virginia Commonwealth University Departamento de botanica Instituto de BiocienciasUniversidade de So Paulo

Molecular phylogenetic studies have become a major area of interest in plant systematics,and their impacts on historical biogeographic hypotheses are not to be disregarded.In Brazil,most historical biogeographic studies have relied on animal phylogenies,whereas plant biogeographic studies have largely lacked a phylogenetic component,having a limited utility for historical biogeography.That country,however,is of great importance for most biogeographic studies of lowland tropical South America,and it includes areas from a number of biogeographic regions of the continent.Important biogeographic reports have been published as part of phylogenetic studies,taxonomic monographs,and regional accounts for small areas or phytogeographic domains,but the available information is subsequently scattered and sometimes hard to find.In this paper we review some relevant angiosperm biogeographic studies in Brazil.Initially we briefly discuss the importance of other continents as source areas for the South American flora.Then we present a subdivision of Brazil into phytogeographic domains,and we cite studies that have explored the detection of biogeographic units(areas of endemism) and how they are historically related among those domains.Examples of plant taxa that could be used to test some biogeographic hypotheses are provided throughout,as well as taxa that exemplify several patterns of endemism and disjunction in the Brazilian angiosperm flora.

关键词： angiosperms biogeography Brazil disjunction distribution patterns endemism.

Hidden in plain sight:Morphological and phylogenetic evidence for Bouteloua arizonica,a species distinct from Bouteloua aristidoides(Poaceae,Chloridoideae)

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Plant Diversity 2021年第2期43卷 125-133页

作者： Luis Fernando Cuellar-Garrido Maria Elena Siqueiros-Delgado Herbario Luz Maria Villarreal de Puga Del Instituto de botanica(IBUG) Departamento de Botanica y ZoologíaCentro Universitario de Ciencias Biologicas y AgropecuariasUniversidad de GuadalajaraCamino Ing.Ramon Padilla Sanchez 2100CP 45200ZapopanJaliscoMexico Departamento de Biologia Centro de Ciencias BioasicasUniversidad Autonoma de AguascalientesAvenida Universidad 940CP 20131AguascalientesMexico

Two varieties of Bouteloua aristidoides have been recognized,the widespread var.aristidoides and the more narrowly distributed var.arizonica.The two varieties differ in inflorescence form even more than that seen between many other closely related species of Bouteloua.We therefore asked whether these taxa might be better regarded as distinct species.A total of 93 vouchers were studied by using morphometry(principal components analysis and statistical tests),leaf micromorphology,ancestral state reconstruction,and/or molecular(ITS,trnC-rpoB and trnT-L-F)phylogenetic analyses.Except from the ITS tree,all results supported elevation of B.aristidoides var.arizonica to the rank of species,thus the new combination Bouteloua arizonica(M.E.Jones)L.F.Cuellar&Columbus comb.***.et stat.nov.,is proposed.Chloroplast and combined chloroplast-nuclear molecular trees depicted var.arizonica as monophyletic(even in sympatric populations with var.aristidoides)and reveals phylogenetic structure within var.aristidoides for which the presence of new undescribed varieties of B.aristidoides(different from B.arizonica)is addressed.B.arizonica differs from B.aristidoides in having fewer branches per inflorescence,a bigger branch with more spikelets,and a shorter branch extension.Scanning electron microscopy revealed the presence of papillae on leaves of B.arizonica as a clear synapomorphy.Growing mature plants of B.arizonica from seeds in a greenhouse revealed a strong cleistogamous nature for this species for which gene flow in sympatric populations with B.aristidoides seems unlikely.A taxonomic treatment and distribution map for identification of B.arizonica is provided.

关键词： Ancestral state reconstruction Bouteloua arizonica Cleistogamy Morphology Phylogeny Sympatry

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3种地中海橡树在叶脉和气孔性状上的个体发育性变化及其与叶片经济性状的关系

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Journal of Plant Ecology 2021年第6期14卷 1090-1104页

作者： Sonia Mediavilla Ignacio Martin Alfonso Escudero Area de Ecologia Facultad de BiologiaUniversidad de SalamancaCampus Miguel de UnamunoSalamanca 37007Spain dpto.de botanica y Fisiologia Vegetal Facultad de BiologiaUniversidad de SalamancaCampus Miguel de UnamunoSalamanca 37007Spain

我们比较了3个地中海栎属(Quercus)树种幼苗和成龄树的叶脉和气孔性状。之前的研究表明,幼苗的气体交换率往往比成龄树的要高。我们的研究目标是确认叶脉和气孔的性状在整个植物个体发育过程中是否会随着气体交换率的变化而同步改变。... 详细信息

我们比较了3个地中海栎属(Quercus)树种幼苗和成龄树的叶脉和气孔性状。之前的研究表明,幼苗的气体交换率往往比成龄树的要高。我们的研究目标是确认叶脉和气孔的性状在整个植物个体发育过程中是否会随着气体交换率的变化而同步改变。我们提出了以下两个备选假设:幼苗比成龄树有着更高的叶脉和气孔密度(假设1);幼苗在维管组织上的投资更少,从而降低了建设成本(假设2)。本研究是在西班牙中西部进行的,我们对每个树种不同生长阶段的植株随机采集了10个样本。我们测量了气孔和叶脉的平均性状(单位叶面积里的气孔大小和数量、叶脉密度、叶脉体积、叶脉到表皮的距离),比叶质量和叶片厚度。研究结果表明,细脉密度和单位面积叶脉体积随着树龄的增加而增加,这似乎与气体交换率方面的个体发育趋势不一致。这种差异支持了我们的假设2,说明植株在幼苗阶段减少对维管组织的投资以最大限度地提高生长速度是其当务之急。幼苗叶片中较大的叶脉间距可以由叶脉到表皮的较短距离所补偿。因此,薄叶片可能是幼苗的一个必要性状,它可以让水分沿较短路径输送到蒸发点,而无需对高成本的维管组织进行大量投资。

关键词：叶脉序叶寿命植物个体发育变化栎属(Quercus)物种气孔特征

ALCUNE STAZIONI DI Isoetes echinospora DUR.NEL BRESCIANO E OSSERVAZIONI AL SEM DELLE SPORE DELLE Isoetes DELLA FLORA ITALICA

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Natural Disaster Reduction in China 1986年第1期 119-130页

作者： CARLO ANDREIS GRAZIELLA RODONDI Dpt.Biologia Sez.botanica Sistematica Università degli Studi Milano. Dpt.Biologia Sez.botanica Sistematica Università degli Studi Milano.

New stations of Isoetes echinospora Dur.in Lombardy are reported.SEM survey on micro-structures of micro-and megaspores of some Isoetes Iiving in Italy are discussed.

关键词： SEM ALCUNE STAZIONI DI Isoetes echinospora DUR.NEL BRESCIANO E OSSERVAZIONI AL SEM DELLE SPORE DELLE Isoetes DELLA FLORA ITALICA PIO 110 UTM Pi ITI

Do assortative mating and immigrant inviability help maintain population genetic structuring of an herbivore on a crop and a wild relative?

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Insect Science 2019年第2期26卷 283-296页

作者： Ricardo Ramirez-Romero Delia Garibay-Benitez Ofelia Vargas-Ponce Andrea Joyce Julio S. Bernal Departamento de Produccion Agricola CUCBA Universidad de Guadalajara Zapopan Jalisco Mexico Departamento de botanica y Zoologia CUCBA Universidad de Guadalajara Zapopan Jalisco Mexico Sierra Nevada Research Institute University of California Merced California USA Department of Entomology Texas A&M University College Station. Texas USA

Population genetic structuring is common among herbivorous insects and frequently is associated with divergent host plants, such as crops and their wild relatives. Previous studies showed population genetic structuring in corn leafhopper Dulbulus maidis in Mexico, such that the species consists of two sympatric, host plant-associated populations: an abundant and widespread "pestiferous” population on maize (Zea mays mays), and a small and localized "wild" population on perennial teosinte (Zea diploperennis). a maize wild relative with a limited distribution. This study addressed whether assortative mating and immigrant inviability mediate genetic structuring of corn leafliopper by comparing the mating and reproductive successes of pestiferous and wild females that colonize their nonassociated host plants against the successes of females colonizing their associated host plants. Assortative mating was assessed by comparing mating frequencies and premating and mating times among females of each population on each host plant: immigrant inviability was assessed by comparing, across two generations, the fecundity, survival, development time, sex ratio, and population growth rate among leafhopper populations and host plants. Our results showed that on maize, and compared to resident, pestiferous females, wild females were more likely to mate, and greater proportions of their offspring survived to adult stage and were daughters;consequently, the per-generation population growth rate on maize was greater for immigrant, wild leafhoppers compared to resident, pestiferous leafhoppers. Our results suggested that wild leafhoppers emigrating to maize have a fitness advantage over resident, pestiferous leafhoppers, while immigrant pestiferous and resident wild leafhoppers on teosinte have similar fitnesses.

关键词： crop domestication Dalbulus maidis ecological speciation host associated differentiation Zea diploperennis Zea mays mays

Selective silencing of 2Cys and type-ⅡB Peroxiredoxins discloses their roles in cell redox state and stress signaling

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Journal of Integrative Plant Biology 2015年第6期57卷 591-601页

作者： Patrícia Vidigal Ana Montserrat Martin-Hernandez Cèlia Guiu-Aragonés Sara Amncio Luísa Carvalho Departamento de Recursos Naturais Ambiente e Território (DRAT)/Centro de Botanica Aplicada à Agricultura (CBAA)Institute of AgronomyUniversity of Lisbon Institut de Recercai Tecnologia Agroalimentàries (IRTA) Centre for Research in Agricultural Genomics (CSIC-IRTA-UAB-UB) Campus Universitat Autonoma de Barcelona (UAB)Edificio Center for Research in Agricultural Genomics (CRAG)

Peroxiredoxins （Prx） catalyse the reduction of hydrogen peroxide （H2O2） and, in association with catalases and other peroxidases, may participate in signal transduction by regulating intercel ular H2O2 concentration that in turn can control gene transcription and cel signaling. Using virus-induced-gene-silencing （VIGS）, 2-Cys Peroxiredoxin （2CysPrx） family and type-II Peroxiredoxin B （PrxI B） gene were silenced in Nicotiana benthamiana, to study the impact that the loss of function of each Prx would have in the antioxidant system under control （22℃） and severe heat stress conditions （48 ℃）. The results showed that both Prxs, although in different organel es, influence the regeneration of ascorbate to a significant extent, but with different purposes. 2CysPrx affects abscisic acid （ABA） biosynthesis through ascorbate, while PrxIIB does it probably;through the xanthophyl cycle. Moreover, 2CysPrx is key in H2O2 scavenging and in consequence in the regulation of ABA signal-ing downstream of reactive oxygen species and PrxIIB provides an important assistance for H2O2 peroxisome scavenges.

关键词： 2-Cys Peroxiredoxin abscisic acid ascorbate heat stress hydrogen peroxide peroxisome type-Ⅱ Peroxiredoxin B

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