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Journal of Plant Ecology 2020年第3期13卷 331-340页

作者： Ernesto Chanes Rodríguez-Ramírez José Antonio Vázquez-García Ignacio García-González Othón Alcántara-Ayala Isolda Luna-Vega laboratorio de Biogeografía y Sistemática Departamento de Biología EvolutivaFacultad de CienciasUniversidad Nacional Autónoma de MéxicoMexico CityMexico laboratorio de Ecosistemática Instituto de BotánicaDepartamento de Botánica y ZoologíaCentro Universitario de Ciencias Biológicas y AgropecuariasUniversidad de GuadalajaraJaliscoMexico departamento de botánica Escola Politécnica Superior de EnxeñaríaUniversidad de Santiago de CompostelaLugoSpain

本文旨在探讨气候变化如何影响两种特有墨西哥木兰的导管性状可塑性和其每年的年轮宽度。尽管如此,很少有研究评估干旱对墨西哥东部热带山地云林导管性状的影响。通过生长年轮的数字图像,我们对所研究的墨西哥木兰树种的径向生长率、树... 详细信息

本文旨在探讨气候变化如何影响两种特有墨西哥木兰的导管性状可塑性和其每年的年轮宽度。尽管如此,很少有研究评估干旱对墨西哥东部热带山地云林导管性状的影响。通过生长年轮的数字图像,我们对所研究的墨西哥木兰树种的径向生长率、树龄和导管性状可塑性进行了评估,比较了两种墨西哥木兰树种在干旱年和非干旱年的导管密度、水力直径和传导面积百分比。本研究首次对墨西哥两个热带山地云林中的两个濒危木兰树种(Magnolia vovidesii和M.schiedeana)的多孔木质部导管性状对长期气候变化的可塑性进行了分析。结果发现,当比较干旱和非干旱年份时,温度和降水量与年轮宽度的差异密切相关。扩散型多孔木质导管解剖结构具有很高的可塑性,这与所研究的两种木兰树种的温度和/或水的有效性有关。我们的结论是,与非干旱年份相比,对干旱年份的解剖学适应导致了导管性状的大量减少;这些可塑的适应性在植物长期环境胁迫下的水分运输以及生存的安全性方面起着重要的作用。

关键词：适应性气候变化干旱与生长关系木兰属植物定量木材解剖

Patterns of climber distribution in temperate forests of the Americas

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Journal of Plant Ecology 2016年第6期9卷 724-733页

作者： Annik Schnitzler Javier Amigo Brack Hale Christophe Schnitzler Laboratoire Interdisciplinaire des Environnements Continentaux(LIEC) UMR 7360 Universitéde LorraineMetzFrance laboratorio de botánica Facultad de FarmaciaUniversidad de Santiago de CompostelaA CoruñaSpain Franklin University Switzerland SorengoSwitzerland Facultédes Sciences du Sport UnistraUniversitéde StrasbourgStrasbourgFrance

Aims and Methods We propose a standard protocol at the landscape to continental scale for examining to what extent the range of ecological conditions found in temperate latitudes explains the variations in climber species richness and traits.The protocol was tested in forests of the two Americas.The data set included 151 climber species.We selected four categorical traits and grouped these species into six clusters with regard to these traits.Floristic records of American forests were first gathered into alliances,second combined with bioclimatic indices(rainfall,temperature,continentality).We obtained a total of 59 vegetational units in which we calculated values of climber species richness and proportion of clusters.Vegetational units were ultimately gathered into five forest formations(characterized by leaf longevity).Wetlands and uplands were considered separately.Important Findings Our results emphasize clear trends in large-scale patterns of climber distribution,independently of taxonomy.Climber species richness(in particular woody climbers)peaks in moist and warm upland forests with oceanic climates,and where conifers are rare.In flooded areas,climber richness is also very high and peaks in seasonally flooded large floodplains.In ecological conditions of frost,dryness or lack of nutrients,climber species richness,abundance and trait diversity decline,resulting in the dominance of small,twining and deciduous life traits.

关键词： American forest bioclimatic indices climber life traits standart protocol species richness

Genetic variation in the reduction of attractive floral traits of an annual tarweed in response to drought and apical damage

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Journal of Plant Ecology 2016年第5期9卷 629-635页

作者： Wilfredo L.Gonzáles Lorena H.Suárez Ernesto Gianoli laboratorio de Ecología Evolutiva LIDFacultad de Ciencias y FilosofíaUniversidad Peruana Cayetano HerediaLimaPerú departamento de Ecología P.Universidad Católica de ChileSantiagoChile departamento de Biología Universidad de La SerenaLa SerenaChile departamento de botánica Universidad de ConcepciónConcepciónChile

Aims Foliar herbivory and water stress may affect floral traits attractive to pollinators.Plant genotypes may differ in their responses to the interplay between these factors,and evolution of phenotypic plasticity could be expected,particularly in heterogeneous environments.We aimed at evaluating the effects of simulated herbivory and experimental drought on floral traits attractive to pollinators in genetic families of the annual tarweed Madia sativa,which inhabits heterogeneous environments in terms of water availability,herbivore abundance and pollinator abundance.Methods In a greenhouse experiment with 15 inbred lines from a M.sativa population located in central Chile(Mediterranean-type climate),we measured the effects of apical bud damage and reduced water availability on:number of ray florets per flower head,length of ray florets,flower head diameter,number of open flower heads per plant,flowering plant height and flowering time.Important Findings Apical damage and water shortage reduced phenotypic expression of floral traits attractive to pollinators via additive and non-additive effects.Plants in low water showed decreased height and had fewer and shorter ray florets,and fewer and smaller flower heads.Damaged plants showed delayed flowering,were less tall,and showed shorter ray florets and smaller flower heads.The number of ray florets was reduced by damage only in the low water treatment.Plant height,flowering time and number of flower heads showed among-family variation.These traits also showed genetic variation for plasticity to water availability.Ray floret length,flower head size and time to flowering showed genetic variation for plastic responses to apical damage.Plasticity in flowering time may allow M.sativa to adjust to the increased aridity foreseen for its habitat.Because genetic variation for plastic responses was detected,conditions are given for evolutionary responses to selective forces acting on plastic traits.We suggest that the evolution of adaptive floral plasticity in M.sativa in this

关键词： flower genetic variation herbivory phenotypic plasticity water availability

A study of chlorophyll-like and phycobilin pigments in the C endosymbiont of the apple- snail Pomacea canaliculata

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BIOCELL 2012年第2期36卷 47-55页

作者： ISRAEL A.VEGA FEdeRICO A.deLLAGNOLA JORGE A.HURST MARTÍN S.GODOY ALFREDO CASTRO-VAZQUEZ laboratorio de Fisiologia(IHEM-CONICET) and Departamento de Morfología y Fisiología(Facultad de Ciencias MédicasUniversidad Nacional de Cuyo)Casilla de Correo 335500 MendozaArgentina Instituto de Ciencias Básicas-Universidad Nacional de Cuyo.Padre Jorge Contreras 1300.Parque Gral.San Martín 5500 Mendoza departamento de Química Biológica.Facultad de Farmacia y Bioquímica Universidad de Buenos Aires.Present address:Instituto de Botánica Darwinion.Labardén 200B1642HYD Buenos Aires

Pigments present in the brown-greenish C morph of an intracellular endosymbiont of Pomacea canaliculata were investigated.Acetone extracts of the endosymbiotic corpuscles showed an absorption spectrum similar to that of chlorophylls.Three fractions obtained from silica gel column chromatography of the acetone extracts(CI,CII and CIII),were studied by positive ion fast atom bombardment-mass spectrometry(FAB–MS)and hydrogen-nuclear magnetic resonance(H-NMR).Results indicated the presence of(1)a sterol in the yellow colored CI fraction;(2)a mixture of pheophorbides a and b in the major green fraction,CII;and(3)a modified pheophorbide a in the smaller green fraction,CIII.Aqueous extracts of the C endosymbiont did not show evidence of the occurrence of C-phycocyanin,allophycocyanin or phycoerithrin(light absorption,fluorescence emission,and electrophoresis of the protein moieties)while cyanobacterial cells(Nostoc sp.)showed evidence of C-phycocyanin and allophycocyanin.The possible phylogenetic and functional significance of the pigments present in the C endosymbiont is discussed.

关键词： symbiosis Cyanobacteria chloroplast photosynthetic pigments phylogeny

Distribution of Malpighia mexicana in Mexico and its implications for Barranca del Río Santiago

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Journal of Forestry Research 2021年第3期32卷 1095-1103页

作者： Martín Tena Meza Rafael MaNavarro-Cerrillo Diego Brizuela Torres Instituto de botánica Centro Universitario de Ciencias Biológicas y AgropecuariasUniversidad de GuadalajaraMéxicoCamino Ramón Padilla Sánchez No.2100.Nextipac45200 ZapopanJaliscoMexico depto.Ingeniería Forestal Laboratorio de SelviculturaDendrocronología y Cambio ClimáticoDendrodatLab-ERSAFUniversidad de CórdobaCampus de RabanalesCtra.N-IVkm.39614071 CórdobaSpain departamento de Producción Forestal Centro Universitario de CienciasBiológicas y AgropecuariasUniversidad de GuadalajaraMéxicoCamino Ramón Padilla Sánchez No.2100 Nextipac45200 ZapopanJaliscoMexico

Wild plants represent relatively unexplored resource of high economic potential,especially as an alternative to developing new crops and,even more relevant,for improving existing crops and contributing to nutrition and health.The wild species M alpighia mexicana(manzanita)has a wide tradition of food,medicinal and ornamental use in Mexico.It is part of the American-origin group of tropical shrubs that produce edible red fruits,such as A cerola,which is considered the most important natural source of vitamin C in the world.Given the role played by M.mexicana in Mexico,and particularly in Barranca del Río Santiago(Santiago River Canyon),we modelled its potential distribution in both geographical areas.We used species'records from databases,local herbaria and records collected by the authors as well as climatic variables representing long term average,variability and extreme conditions of temperature and precipitation.To fit the models we used the modelling algorithm Maxent and selected an adequate configuration by testing a range of model complexity settings.The results indicate a clear species preference for warm-dry tropical forest,most extensively in the Balsas river depression and the central valleys of Oaxaca.The probability of the species presence in the western region was also high,although the probability was also high for smaller surface areas,such as the region of Santiago river canyons,which are covered by warm-dry tropical forests.

关键词： Malpighia mexicana Maxent Warmdry tropical forest Río Santiago Genetic resources Ecological niche model Manzanita

Benefits of a root fungal endophyte on physiological processes and growth of the vulnerable legume tree Prosopis chilensis(Fabaceae)

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Journal of Plant Ecology 2019年第2期12卷 264-271页

作者： Marcia González-Teuber Alejandro Urzúa Andrea Morales Cristian Ibáñez Luisa Bascuñán-Godoy Max Planck Partner Group Departamento de Ciencias del AmbienteUniversidad de Santiago de ChileAv.Libertador Bernardo O'Higgins 3363SantiagoChile Instituto de Investigación Multidisciplinario en Ciencias y Tecnología Universidad de La SerenaAv.Raúl Bitrán 1305La SerenaChile laboratorio de Química Ecológica Universidad de Santiago de ChileAv.Libertador Bernardo O'Higgins 3363SantiagoChile departamento de Biología Universidad de La SerenaAv.Raúl Bitrán 1305La SerenaChile departamento de botánica Universidad de ConcepciónBarrio Universitario s/nConcepciónChile

Aims desertification is a major concern in arid and semi-arid regions globally.Understanding interactions between vulnerable plant spe-cies and associated microbial symbionts may have important appli-cations for conservation and restoration strategies in affected areas.Methods In this study,we evaluated the root-associated fungal endophyte community in Prosopis chilensis,a vulnerable and threatened arid-adapted tree of northern Chile.Host benefits in terms of physiologi-cal performance and plant growth were also assessed.Endophytic fungi were isolated from asymptomatic roots by the culture method for molecular identification of the 18S rRNA gene.The dominant fungal endophyte(Penicillium sp.)in the community was later used in inoculation experiments to assess its effect on maximum quan-tum efficiency of photosystem II(_(PSII)),(Fv/Fm)actual _(PSII) efficiency(Φ_(PSII)),and non-photochemical quenching(NPQ).Total sugars,starch content,malonaldehyde(MDA),nitrogen content(%)and growth traits were also measured.Important Findings WhereasΦ_(PSII) increased significantly in endophyte-inoculated plants,NPQ was found to decrease.No effect of endophyte inocula-tion on sugars and MDA was detected,but starch content,leaf nitro-gen content,number of leaves and shoot biomass were found to increase.Results revealed that inoculation of endophytic Penicillium fungal isolate can provide significant physiological benefits to the host plant P.chilensis.Its presence resulted in greater _(PSII) efficiency and higher leaf nitrogen and carbohydrate content,enhancing host plant growth.These findings highlight the importance of consider-ing the fungal endophyte community of this vulnerable species as an important tool to the design of further revegetation and conserva-tion programs.

关键词： root endophytic fungi PSII efficiency nitrogen content plant growth promotion starch accumulation arid habitats

Inhibition of Acinetobacter baumannii Biofilm Formation by Methanolic Extract of Nothoscordum bivalve

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Advances in Microbiology 2018年第5期8卷 422-438页

作者： Hernández-Marín David Alejandro Munoz-Ortega Martín Humberto Guevara-Lara Fidel Gúzman-Lucio Marco Antonio Sánchez-García Eduardo laboratorio de Química Analítica Facultad de Ciencias BiológicasUniversidad Autónoma de Nuevo LeónSan Nicolás de los GarzaNuevo LeónMéxico laboratorio de Patología Molecular Experimental Departamento de QuímicaCentro de Ciencias BásicasUniversidad Autónoma de AguascalientesAguascalientesMéxico laboratorio de Biotecnología y Funcionalidad de Alimentos Departamento de QuímicaCentro de Ciencias BásicasUniversidad Autónoma de AguascalientesAguascalientesMéxico departamento de botánica Facultad de Ciencias BiológicasUniversidad Autónoma de Nuevo LeónMonterreyNuevo LeónMéxico

Acinetobacter baumannii is one of the most prevalent pathogens in nosocomial infections and has been cause of concern in recent years because, it has presented multiresistance to antibiotics and besides can form biofilms on biotic and abiotic surfaces like tissues and medical devices. Therefore, the search for new alternatives of natural origin to inhibit biofilm formation is being conducted. In the present investigation, sub-lethal concentrations (5.61 mg/mL, 3.74 mg/mL and 1.87 mg/mL) of methanolic extract of Nothoscordum bivalve were evaluated, showing biofilm formation inhibition up to 40.8%, in one nosocomial isolated of A. baumannii by the microtiter biofilm formation assay using crystal violet. On the other hand, the concentrations of 5.61 mg/mL and 3.74 mg/mL, caused an overexpression (up to 15.4 times) in the genes involved in the formation of biofilm (abaI, bap and csuE);due to this, the interaction of the extract with the bacteria was analyzed by scanning electron microscopy (SEM) and cellular damage was observed in the structure and stability of biofilm.

关键词： Biofilm Sub-Lethal Nothoscordum bivalve Acinetobacter baumannii

XAANTAL2 （AGL14） Is an Important Component of the Complex Gene Regulatory Network that Underlies Arabidopsis Shoot Apical Meristem Transitions

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Molecular Plant 2015年第5期8卷 796-813页

作者： Rigoberto V. Perez-R.u.iz Berenice Garcia-Ponce Nayelli Marsch-Martinez Yamel Ugartechea-Chirino Mitzi Villajuana-Bonequi Stefan de Folter Eugenio Azpeitia Jose Davila-Velderrain David Cruz-Sanchez Adriana Garay-Arroyo Maria de la Paz Sanchez Juan M. Estevez-Palmas Elena R. Alvarez-Buylla Instituto de Ecologia Universidad Nacionat Autonoma de Moxico 3er Circuito Exterior s/no Junto al Jardin Bot~nico and Centro de Ciencias de la ComplejidadCiudad Universitaria Coyoacan 04510 Mexico D.F. Mexico laboratorio Nacional de Genemica para la Biodiversidad (Langebio) Centro de Investigaci6n y de Estudios Avanzados del Instituto Polit~cnico Nacional(CINVESTAV-IPN) Km. 9.6 Carretera Irapuato - Leen AP 629 36821 Irapuato Guanajuato Mexico University of California 431 Koshland Hall Berkeley CA 94720 USA These authors contributed equally to this article. present address: departamento de Biotecnologia y Biquimica Centro de )nvestigaci6n y de Estudios Avanzados del Instituto Polit6cnico Nacional(CINVESTAV-IPN) Km. 9.6 Libramiento Norte Carr. Irapuato-Leen 36821 Irapuato Guanajuato Mexico present address: Max Planck Institute for Plant Breeding Research D-50829 Cologne Germany Present address: INRIA Project-Team Virtual Plants/CIRAD/INRA UMR AGAP Campus St Priest - BAT 5 CC 05018 860 rue de St Priest 34095 Montpellier Cedex5 France

In Arabidopsis thaliana, multiple genes involved in shoot apical meristem （SAM） transitions have been char- acterized, but the mechanisms required for the dynamic attainment of vegetative, inflorescence, and floral meristem （VM, IM, FM） cell fates during SAM transitions are not well understood. Here we show that a MADS-box gene, XAANTAL2 （XAL2/AGL14）, is necessary and sufficient to induce flowering, and its regula- tion is important in FM maintenance and determinacy, xal2 mutants are late flowering, particularly under short-day （SD） condition, while XAL2 overexpressing plants are early flowering, but their flowers have vege- tative traits. Interestingly, inflorescences of the latter plants have higher expression levels of LFY, AP1, and TFL1 than wild-type plants. In addition we found that XAL2 is able to bind the TFL1 regulatory regions. On the other hand, the basipetal carpels of the 35S：：XAL2 lines lose determinacy and maintain high levels of WUS expression under SD condition. To provide a mechanistic explanation for the complex roles of XAL2 in SAM transitions and the apparently paradoxical phenotypes of XAL2 and other MADS-box （SOCl, AGL24） over- expressors, we conducted dynamic gene regulatory network （GRN） and epigenetic landscape modeling. We uncovered a GRN module that underlies VM, IM, and FM gene configurations and transition patterns in wild- type plants as well as loss and gain of function lines characterized here and previously. Our approach thus provides a novel mechanistic framework for understanding the complex basis of SAM development.

关键词： XAL2/AGL14 MADS-box TFL1 SAM transitions floral reversion gene regulatory networks,epigenetic landscape modeling

Tree community composition,structure and diversity along an elevational gradient in an Andean forest of Northern Ecuador

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Journal of Mountain Science 2021年第9期18卷 2315-2327页

作者： JIMÉNEZ-PAZ Rosa WORTHY Samantha J VALENCIA Renato PÉREZÁlvaro J REYNOLDS Alex BARONE John A BURGESS Kevin S laboratorio de Ecología de Plantas Escuela de Ciencias BiológicasFacultad de Ciencias Exactas y NaturalesPontificia Universidad Católica del EcuadorQuito 17-01-2184Ecuador department of Biology College of Letters&SciencesColumbus State UniversityColumbusGeorgia 31907USA Herbario QCA Escuela de Ciencias BiológicasFacultad de Ciencias Exactas y NaturalesPontificia Universidad Católica del EcuadorQuito 17-01-2184Ecuador The Lovett School AtlantaGeorgia 30327USA

The Andean forests of northern Ecuador are known for their high levels of plant diversity relative to the area they occupy.Typically,these forests grow on steep slopes that lead to dramatic habitat gradients across short distances.These extreme habitat gradients make the Andean forest ecosystem an excellent natural laboratory for understanding the effect of elevation on forest community diversity,structure and composition.We established 31 plots(50 m×5 m)which are divided between two elevational transects in the cloud forest of the Siempre Verde Reserve in the western foothills of the Andes Mountains of northern Ecuador.All trees and tree ferns with a diameter at breast height(dbh)≥5 cm were measured and identified.We examined changes in community composition,structure,and diversity along and between the elevational transects and three elevational zones:low(2437–2700 m),middle(2756–3052 m),and high(3163–3334 m).We found four main trends associated with the elevational gradients at this site:(1)community composition differed between the two transects and among the three elevational zones according to N-MDS,ANOSIM,and percentage of shared species,with some species having limited distributions,(2)metrics of community structure showed opposite relationships with elevation,depending on the transect,with the only significant relationship(negative)found between basal area and elevation in the open trail transect,(3)alpha diversity,in general,peaked at mid-elevations,and(4)beta diversity consistently increased with distance between plots along elevation.The complexity of changes in community composition,structure,and alpha diversity along elevation may be related to the heterogeneity of the environment on a local scale,such as topography,soil composition,and even human impact,or to dispersal limitation and should be investigated further.These changes in community composition and the relatively high beta diversity found at this site exemplify the biological complexity of montane forest,reinforcing arguments from other stu

关键词： Elevational gradient Cloud forest Andes Structure Composition Diversity