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Showing 1 - 200 of 718 Journals sorted alphabetically
ABCD. Arquivos Brasileiros de Cirurgia Digestiva     Open Access   (Followers: 2, SJR: 0.277, h-index: 5)
ACIMED     Open Access   (Followers: 1)
Acta Agronómica     Open Access   (Followers: 1, SJR: 0.11, h-index: 2)
Acta Amazonica     Open Access   (Followers: 3, SJR: 0.32, h-index: 18)
Acta Bioethica     Open Access   (Followers: 1, SJR: 0.131, h-index: 4)
Acta Botanica Brasilica     Open Access   (Followers: 2, SJR: 0.364, h-index: 23)
Acta botánica mexicana     Open Access   (Followers: 1, SJR: 0.251, h-index: 6)
Acta Cirurgica Brasileira     Open Access   (SJR: 0.319, h-index: 19)
Acta Limnologica Brasiliensia     Open Access   (Followers: 3, SJR: 0.29, h-index: 6)
Acta Literaria     Open Access   (Followers: 3, SJR: 0.1, h-index: 2)
Acta Medica Colombiana     Open Access   (Followers: 1)
Acta Médica Costarricense     Open Access   (Followers: 2)
Acta Neurológica Colombiana     Open Access   (Followers: 1)
Acta Ortopédica Brasileira     Open Access   (Followers: 1, SJR: 0.288, h-index: 10)
Acta Paulista de Enfermagem     Open Access   (Followers: 2, SJR: 0.242, h-index: 15)
Acta Pediátrica Costarricense     Open Access   (Followers: 1)
Acta Scientiarum. Agronomy     Open Access   (Followers: 4, SJR: 0.961, h-index: 15)
Acta zoológica mexicana     Open Access  
Actualidades Biológicas     Open Access   (Followers: 1)
African Human Rights Law J.     Open Access   (Followers: 18)
African Natural History     Open Access   (Followers: 2, SJR: 0.106, h-index: 4)
Afro-Asia     Open Access  
Ágora - studies in psychoanalytic theory     Open Access   (Followers: 3, SJR: 0.101, h-index: 2)
Agricultura Tecnica     Open Access   (Followers: 6)
Agrociencia     Open Access   (Followers: 1, SJR: 0.213, h-index: 15)
Agrociencia Uruguay     Open Access  
Agronomía Mesoamericana     Open Access  
Aisthesis     Open Access   (Followers: 4, SJR: 0.1, h-index: 1)
Alea : Estudos Neolatinos     Open Access   (Followers: 1, SJR: 0.1, h-index: 3)
Alfa : Revista de Linguística     Open Access  
Alpha (Osorno)     Open Access   (SJR: 0.114, h-index: 3)
Ambiente & sociedade     Open Access   (Followers: 2, SJR: 0.142, h-index: 8)
Ambiente & Agua : An Interdisciplinary J. of Applied Science     Open Access   (Followers: 1, SJR: 0.221, h-index: 4)
Ambiente Construído     Open Access   (Followers: 1)
América Latina en la historia económica     Open Access   (Followers: 2, SJR: 0.148, h-index: 1)
Anais Brasileiros de Dermatologia     Open Access   (Followers: 2, SJR: 0.498, h-index: 23)
Anais da Academia Brasileira de Ciências     Open Access   (Followers: 2, SJR: 0.322, h-index: 42)
Anais do Museu Paulista : História e Cultura Material     Open Access   (Followers: 1)
Anales de Medicina Interna     Open Access   (Followers: 1)
Anales del Instituto de la Patagonia     Open Access   (Followers: 1)
Anales del Sistema Sanitario de Navarra     Open Access   (Followers: 1, SJR: 0.196, h-index: 18)
Análise Psicológica     Open Access   (Followers: 1, SJR: 0.129, h-index: 3)
Análise Social     Open Access   (Followers: 1, SJR: 0.109, h-index: 8)
Andean geology     Open Access   (Followers: 13, SJR: 0.997, h-index: 25)
Annali dell'Istituto Superiore di Sanità     Open Access   (SJR: 0.318, h-index: 29)
Antipoda. Revista de Antropología y Arqueología     Open Access   (Followers: 5, SJR: 0.1, h-index: 0)
Anuario Colombiano de Historia Social y de la Cultura     Open Access   (SJR: 0.101, h-index: 1)
Anuario de Historia Regional y de las Fronteras     Open Access  
Apuntes : Revista de Estudios sobre Patrimonio Cultural - J. of Cultural Heritage Studies     Open Access   (Followers: 4)
Archivos de Medicina Veterinaria     Open Access   (Followers: 2, SJR: 0.199, h-index: 16)
Archivos de Neurociencias     Open Access   (Followers: 3, SJR: 0.1, h-index: 4)
Archivos de Pediatria del Uruguay     Open Access   (Followers: 3)
Archivos de Zootecnia     Open Access   (Followers: 1, SJR: 0.248, h-index: 9)
Archivos Españoles de Urología     Open Access   (SJR: 0.188, h-index: 19)
ARQ     Open Access   (Followers: 4, SJR: 0.1, h-index: 2)
Arquitectura y Urbanismo     Open Access   (Followers: 2)
Arquivo Brasileiro de Medicina Veterinária e Zootecnia     Open Access   (SJR: 0.307, h-index: 22)
Arquivos Brasileiros de Cardiologia     Open Access   (Followers: 1, SJR: 0.334, h-index: 32)
Arquivos Brasileiros de Endocrinologia e Metabologia     Open Access  
Arquivos Brasileiros de Oftalmologia     Open Access   (SJR: 0.308, h-index: 19)
Arquivos de Gastroenterologia     Open Access   (Followers: 1, SJR: 0.424, h-index: 22)
Arquivos de Medicina     Open Access   (SJR: 0.1, h-index: 5)
Arquivos de Neuro-Psiquiatria     Open Access   (SJR: 0.374, h-index: 38)
Arquivos do Instituto Biológico     Open Access   (Followers: 1)
Arquivos Internacionais de Otorrinolaringologia     Open Access  
ARS     Open Access   (Followers: 2)
Atenea (Concepción)     Open Access   (SJR: 0.111, h-index: 3)
Atmósfera     Open Access   (Followers: 2, SJR: 0.377, h-index: 18)
Audiology - Communication Research     Open Access   (Followers: 9)
Avaliação : Revista da Avaliação da Educação Superior (Campinas)     Open Access  
Avances en Odontoestomatologia     Open Access   (Followers: 1, SJR: 0.109, h-index: 4)
Avances en Periodoncia e Implantología Oral     Open Access   (Followers: 1)
Bakhtiniana : Revista de Estudos do Discurso     Open Access  
BAR. Brazilian Administration Review     Open Access   (Followers: 1, SJR: 0.188, h-index: 6)
Biota Neotropica     Open Access   (SJR: 0.373, h-index: 18)
Biotecnología Aplicada     Open Access   (SJR: 0.122, h-index: 10)
Biotecnología en el Sector Agropecuario y Agroindustrial     Open Access  
Boletim de Ciências Geodésicas     Open Access   (SJR: 0.227, h-index: 5)
Boletim do Museu Paraense Emílio Goeldi. Ciências Humanas     Open Access   (Followers: 1, SJR: 0.139, h-index: 4)
Boletin Chileno de Parasitologia     Open Access  
Boletín de Filología     Open Access  
Boletín de la Sociedad Botánica de México     Open Access  
Boletin de la Sociedad Chilena de Quimica     Open Access  
Boletín de la Sociedad Geológica Mexicana     Open Access   (SJR: 0.231, h-index: 8)
Boletín del Museo Chileno de Arte Precolombino     Open Access   (Followers: 1, SJR: 0.149, h-index: 1)
Bosque     Open Access   (Followers: 2, SJR: 0.256, h-index: 10)
Bragantia     Open Access   (Followers: 2, SJR: 0.522, h-index: 20)
Brazilian Archives of Biology and Technology     Open Access   (Followers: 3, SJR: 0.242, h-index: 31)
Brazilian Dental J.     Open Access   (Followers: 2, SJR: 0.47, h-index: 34)
Brazilian J. of Biology     Open Access   (Followers: 3, SJR: 0.358, h-index: 35)
Brazilian J. of Chemical Engineering     Open Access   (Followers: 3, SJR: 0.424, h-index: 32)
Brazilian J. of Food Technology     Open Access   (Followers: 3)
Brazilian J. of Medical and Biological Research     Open Access   (SJR: 0.541, h-index: 70)
Brazilian J. of Microbiology     Open Access   (Followers: 3, SJR: 0.39, h-index: 38)
Brazilian J. of Oceanography     Open Access   (Followers: 1, SJR: 0.285, h-index: 13)
Brazilian J. of Oral Sciences     Open Access   (Followers: 1, SJR: 0.145, h-index: 6)
Brazilian J. of Physical Therapy     Open Access   (SJR: 0.466, h-index: 16)
Brazilian J. of Plant Physiology     Open Access   (Followers: 3, SJR: 0.452, h-index: 32)
Brazilian J. of Veterinary Research and Animal Science     Open Access   (Followers: 7, SJR: 0.184, h-index: 10)
Brazilian Oral Research     Open Access  
Brazilian Political Science Review     Open Access  
Bulletin of the World Health Organization     Open Access   (Followers: 15, SJR: 2.819, h-index: 123)
Caderno CRH     Open Access   (SJR: 0.102, h-index: 4)
Caderno de Estudos     Open Access  
Cadernos CEDES     Open Access   (Followers: 1, SJR: 0.111, h-index: 5)
Cadernos de Pesquisa     Open Access   (Followers: 2, SJR: 0.26, h-index: 8)
Cadernos de Saúde Pública     Open Access   (Followers: 1, SJR: 0.593, h-index: 55)
Cadernos de Tradução     Open Access  
Cadernos Metrópole     Open Access  
Cadernos Nietzsche     Open Access  
Cadernos Pagu     Open Access   (SJR: 0.179, h-index: 4)
Cadernos Saúde Coletiva     Open Access   (Followers: 1)
Calidad en la educación     Open Access   (Followers: 1)
Cerâmica     Open Access   (Followers: 4, SJR: 0.19, h-index: 11)
CES Medicina     Open Access  
Chilean J. of Agricultural Research     Open Access   (Followers: 1, SJR: 0.366, h-index: 15)
Chungara (Arica) - Revista de Antropologia Chilena     Open Access   (Followers: 1, SJR: 0.49, h-index: 13)
Ciência & Educação (Bauru)     Open Access  
Ciência & Saúde Coletiva     Open Access   (Followers: 2, SJR: 0.588, h-index: 30)
Ciência Animal Brasileira     Open Access   (SJR: 0.322, h-index: 4)
Ciência da Informação     Open Access   (Followers: 1, SJR: 0.117, h-index: 7)
Ciencia del suelo     Open Access   (Followers: 2, SJR: 0.206, h-index: 13)
Ciência e Agrotecnologia     Open Access   (SJR: 0.444, h-index: 19)
Ciencia e Cultura     Open Access   (Followers: 1)
Ciencia e investigación agraria     Open Access   (Followers: 1, SJR: 0.21, h-index: 10)
Ciencia forestal en México     Open Access  
Ciência Rural     Open Access   (Followers: 2, SJR: 0.389, h-index: 24)
Ciencia y Enfermeria - Revista Iberoamericana de Investigacion     Open Access   (Followers: 3, SJR: 0.165, h-index: 7)
Ciencias Marinas     Open Access   (Followers: 2, SJR: 0.348, h-index: 21)
Ciencias Psicológicas     Open Access  
Cirugia Plastica Ibero-Latinoamericana     Open Access   (SJR: 0.175, h-index: 8)
CLEI Electronic J.     Open Access  
Clínica y Salud     Open Access   (SJR: 0.15, h-index: 3)
Clinics     Open Access   (SJR: 0.525, h-index: 36)
CoDAS     Open Access   (SJR: 0.177, h-index: 12)
Computación y Sistemas     Open Access   (SJR: 0.253, h-index: 4)
Comuni@cción     Open Access  
Comunicación y sociedad     Open Access   (Followers: 2, SJR: 0.104, h-index: 1)
Contaduría y Administración     Open Access   (SJR: 0.103, h-index: 1)
Contexto Internacional     Open Access  
Convergencia     Open Access   (SJR: 0.112, h-index: 4)
Correo Científico Médico     Open Access  
Corrosão e Protecção de Materiais     Open Access  
Crop Breeding and Applied Biotechnology     Open Access   (Followers: 4, SJR: 0.604, h-index: 13)
Cuadernos de Economía     Open Access   (Followers: 1)
Cuadernos de Economia - Latin American J. of Economics     Open Access   (Followers: 1)
Cuadernos de Historia     Open Access   (Followers: 3)
Cuadernos de Historia de la Salud Publica     Open Access  
Cuadernos de Medicina Forense     Open Access   (Followers: 2, SJR: 0.106, h-index: 4)     Open Access   (SJR: 0.117, h-index: 2)
Cubo. A Mathematical J.     Open Access  
Cuicuilco     Open Access   (Followers: 1)
Cultivos Tropicales     Open Access  
Culturales     Open Access   (Followers: 2)
Dados - Revista de Ciências Sociais     Open Access   (SJR: 0.429, h-index: 15)
De Jure     Open Access   (Followers: 1)
DELTA : Documentação de Estudos em Lingüística Teórica e Aplicada     Open Access   (SJR: 0.142, h-index: 5)
Dementia & Neuropsychologia     Open Access   (Followers: 5, SJR: 0.232, h-index: 10)
Dental Press J. of Orthodontics     Open Access   (Followers: 2, SJR: 0.214, h-index: 7)
Desacatos     Open Access   (Followers: 1)
Desarrollo y Sociedad     Open Access   (Followers: 3, SJR: 0.106, h-index: 2)
Diálogo Andino - Revista de Historia, Geografía y Cultura Andina     Open Access  
Diánoia     Open Access   (Followers: 1)
Dimensión Empresarial     Open Access  
Dynamis : Acta Hispanica ad Medicinae Scientiarumque Historiam Illustrandam     Open Access   (Followers: 1, SJR: 0.134, h-index: 7)
e-J. of Portuguese History     Open Access   (Followers: 2, SJR: 0.125, h-index: 2)
Eclética Química     Open Access   (Followers: 1)
Ecología en Bolivia     Open Access  
Economia Aplicada     Open Access   (SJR: 0.168, h-index: 6)
Economia e Sociedade     Open Access  
EconoQuantum     Open Access  
Educação & Sociedade     Open Access   (Followers: 3, SJR: 0.244, h-index: 12)
Educação e Pesquisa     Open Access   (Followers: 1, SJR: 0.171, h-index: 8)
Educação em Revista     Open Access  
Educación Matemática     Open Access  
Educación Médica     Open Access   (Followers: 1, SJR: 0.11, h-index: 7)
Educación Médica Superior     Open Access   (Followers: 1, SJR: 0.188, h-index: 7)
Educación y Educadores     Open Access   (Followers: 1)
Educar em Revista     Open Access  
EDUMECENTRO     Open Access  
En-Claves del pensamiento     Open Access   (Followers: 1)
Encuentros     Open Access  
Ene : Revista de Enfermería     Open Access  
Enfermería Global     Open Access   (Followers: 3, SJR: 0.14, h-index: 2)
Enfermería Nefrológica     Open Access   (Followers: 1)
Engenharia Agrícola     Open Access   (SJR: 0.396, h-index: 18)
Engenharia Sanitaria e Ambiental     Open Access   (SJR: 0.15, h-index: 10)
Ensaio Avaliação e Políticas Públicas em Educação     Open Access   (Followers: 1, SJR: 0.19, h-index: 6)
Entomologia y Vectores     Open Access   (Followers: 2)
Escritos de Psicología : Psychological Writings     Open Access   (Followers: 2)
Estudios Atacameños     Open Access   (Followers: 2, SJR: 0.418, h-index: 8)
Estudios Constitucionales     Open Access   (Followers: 4, SJR: 0.383, h-index: 5)
Estudios de Cultura Maya     Open Access   (Followers: 3, SJR: 0.167, h-index: 1)
Estudios de Economía     Open Access   (SJR: 0.144, h-index: 7)
Estudios de historia moderna y contemporánea de México     Open Access   (SJR: 0.101, h-index: 3)
Estudios Filologicos     Open Access   (SJR: 0.105, h-index: 3)
Estudios Fronterizos     Open Access   (Followers: 1)
Estudios internacionales     Open Access   (Followers: 5)
Estudios Pedagogicos (Valdivia)     Open Access   (Followers: 2, SJR: 0.209, h-index: 7)
Estudios Políticos     Open Access  

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Journal Cover Acta Botanica Brasilica
  [SJR: 0.364]   [H-I: 23]   [2 followers]  Follow
  This is an Open Access Journal Open Access journal
   ISSN (Print) 0102-3306
   Published by SciELO Homepage  [718 journals]
  • Different physiological responses under drought stress result in different
           recovery abilities of two tropical woody evergreen species

    • Abstract: ABSTRACT The effects of water deficit on physiological and biochemical variables of young plants of two tropical woody species, Pachira aquatica and Sterculia foetida, and their recovery abilities were measured. Leaf water potential, gas exchange and selected carbon metabolism components were measured in a greenhouse experiment with control, moderate and severe water deficit treatments. Under severe drought stress, gas exchange and chlorophyll fluorescence decreased in both species compared to their respective controls. After rehydration, P. aquatica and S. foetida showed a partial and full recovery of the measured variables, respectively. In addition, a decrease and an increase in photosynthetic pigments were observed for P. aquatica and S. foetida, respectively, compared to their controls. In conclusion, the two species showed differing responses regarding photosynthetic pigment content dynamics for tolerating water deficit. Individuals of P. aquatica in the severe water deficit treatment showed a decrease in pigments, which may have impaired the recovery of metabolism (gas exchange) after rehydration, while S. foetida experienced an increase, favoring a full recovery of gas exchange and biochemical metabolism after rehydration.
  • Phytoremediation of arsenic-contaminated water: the role of antioxidant
           metabolism of Azolla caroliniana Willd. (Salviniales)

    • Abstract: ABSTRACT Phytoremediation has proven to be an efficient technology for removing arsenic (As) from water, but the plants used in this process need to be tolerant to the damage caused by As. The toxic effect of As on growth and functioning of the antioxidant system was studied in individual plants of Azolla caroliniana exposed to five concentrations of As (0.0, 0.25, 0.5, 1.0 and 1.5 mg L-1) for the course of five days. Growth, As absorption, enzymatic activity, total and non-protein thiols and anthocyanin content were assessed. Azolla caroliniana was able to take up large amounts of the pollutant, reaching As concentrations of 386.1 µg g-1 dry weight without saturating the absorption mechanism. The tolerance index and the growth of A. caroliniana decreased with the increased As uptake. Superoxide dismutase, peroxidases, catalases and glutathione reductase activities increased at lower doses of As and subsequently declined with higher concentrations, whereas ascorbate peroxidase activity was reduced in all treatments. Unlike the enzymatic defence system, anthocyanin and thiol content increased consistently in all treatments and showed a positive correlation with As concentration. Therefore, the increased synthesis of non-enzymatic antioxidants is most likely the main factor responsible for the high As tolerance of A. caroliniana.
  • Temporal evaluation of the Conservation Priority Index for medicinal

    • Abstract: ABSTRACT We investigated, through a temporal comparison, the extraction of non-timber forest resources by quantitatively analyzing the Conservation Priority Index (CPI). The study focused on the Fulni-ô Indigenous Territory, in the municipality of Águas Belas, PE (Northeast Brazil), which is characterized by caatinga vegetation (seasonal dry forest). Information on the availability of the exploited resources and the reported use of the species were obtained from vegetation sampling and semi-structured interviews, respectively. Our results demonstrated a reduction in species richness overtime, which may be due to continued resource extraction in the area, and that some species with low densities were even more affected. The species reported as being at high risk in the current study apparently did not differ from their status in the previous study, which supports the idea that these species are most evident in this situation more for their high potential of use than for their high densities. When we associate these events together with the disappearance of some rare species, we can conclude that the CPI was not efficient in predicting changes, and that the combination of variables used with the biological variables of the species needs to be adjusted.
  • Metabolic responses and β-carotene production by the unicellular green
           alga Dunaliella salina exposed to leaf extracts

    • Abstract: ABSTRACT The present work investigated the effects of aqueous extracts of eucalyptus ( Eucalyptus globulus) and elderberry ( Sambucus ebulus) leaves on β-carotene productivity in Dunaliella salina, a green microalga. Leaf extracts from eucalyptus have greater amounts of phenolics and flavonoids, as well as greater ferric reducing antioxidant potential than elderberry. The extracts of both species greatly inhibited growth of algal suspensions. However, chlorophyll and β-carotene concentration increased in cells treated with leaf extracts, and the highest values were detected in 1 % eucalyptus and 2 % elderberry extracts. Fresh weight, total sugar, and protein content significantly increased following exposure of cells to different doses of leaf extracts. However, in doses containing more than 2 % eucalyptus, the upward trend for total sugar and protein ceased and remained statistically unchanged. These results suggest that metabolic modifications enable D. salina cells to tolerate the stress induced by the leaf extracts through allocating carbon flux to the synthesis of osmolytes and putative antioxidant molecules (e.g. sugars and β-carotene). Therefore, the use of leaf extracts holds potential to be a promising and effective way to improve D. salina cultivation for β-carotene production and other biotechnological and industrial applications.
  • Updated angiosperm family tree for analyzing phylogenetic diversity and
           community structure

    • Abstract: ABSTRACT The computation of phylogenetic diversity and phylogenetic community structure demands an accurately calibrated, high-resolution phylogeny, which reflects current knowledge regarding diversification within the group of interest. Herein we present the angiosperm phylogeny, which is based on the topology proposed by the Angiosperm Phylogeny Group IV, a recently released compilation of angiosperm diversification. is calibratable by different sets of recently published estimates of mean node ages. Its application for the computation of phylogenetic diversity and/or phylogenetic community structure is straightforward and ensures the inclusion of up-to-date information in user specific applications, as long as users are familiar with the pitfalls of such hand-made supertrees.
  • Floristic and ecological characterization of habitat types on an inselberg
           in Minas Gerais, southeastern Brazil

    • Abstract: ABSTRACT Inselbergs are granitic or gneissic rock outcrops, distributed mainly in tropical and subtropical regions. They are considered terrestrial islands because of their strong spatial and ecological isolation, thus harboring a set of distinct plant communities that differ from the surrounding matrix. In Brazil, inselbergs scattered in the Atlantic Forest contain unusually high levels of plant species richness and endemism. This study aimed to inventory species of vascular plants and to describe the main habitat types found on an inselberg located in the state of Minas Gerais, in southeastern Brazil. A total of 89 species of vascular plants were recorded (belonging to 37 families), of which six were new to science. The richest family was Bromeliaceae (10 spp.), followed by Cyperaceae (seven spp.), Orchidaceae and Poaceae (six spp. each). Life forms were distributed in different proportions between habitats, which suggested distinct microenvironments on the inselberg. In general, habitats under similar environmental stress shared common species and life-form proportions. We argue that floristic inventories are still necessary for the development of conservation strategies and management of the unique vegetation on inselbergs in Brazil.
  • Allelopathic suppression by Conyza canadensis depends on the interaction
           between latitude and the degree of the plant’s invasion

    • Abstract: ABSTRACT Allelopathic suppression of the growth of co-occurring plant species in invaded ecosystems is an important factor in some plant invasions. This study uses leaf extracts of the invasive plant species Conyza canadensis to determine its allelopathic effects along a latitudinal gradient, and under different cover classes and degrees of invasion, on seed germination and growth of Lactuca sativa, a sensitive bioindicator of allelochemicals. The allelopathic effects of C. canadensis on seedling height, root length, seedling biomass, germination percentage, germination potential, germination index, germination rate index, and vigor index of L. sativa increased significantly with increasing latitude. A possible explanation is that the leaves of plants growing in high latitudes secrete a higher concentration of allelochemicals than do leaves of plants growing in low latitudes. The allelopathic effects of C. canadensis on seedling height, seedling biomass, germination potential, germination index, germination rate index, and vigor index of L. sativa decreased with increasing degree of invasion. The more intense allelopathic effects of C. canadensis at lower degrees of invasion may enable it to establish populations in ecosystems by inhibiting the seed germination and growth of co-occurring species.
  • Effect of some environmental factors on seed germination of Eryngium
           caeruleum M. Bieb. populations

    • Abstract: ABSTRACT The effects of alternating and constant temperatures and light regimes, osmotic and salt stress and pH were tested on seed germination in four populations of Eryngium caeruleum. Laboratory experiments revealed that the four populations exhibited different responses to alternating temperature and light conditions. Alternating temperature and photoperiod had a greater positive effect on seed germination compared to complete darkness. The optimal constant temperature within 10 ºC to 15 ºC for seed germination of each population was determined in a light/dark photoperiod. Seed germination severely decreased under water stress and was completely inhibited at -0.8 MPa osmotic potential. Saline stress sharply decreased germination percentage. Germination was restricted by pH lower and higher than 5 and 8, respectively. The information obtained from this study helps to fill the gap of knowledge about seed germination requirements of E. caeruleum and enhance our understanding of this species distribution and its potential to develop in stressful and/or new habitats.
  • Effects of sex and altitude on nutrient, and carbon and nitrogen stable
           isotope composition of the endangered shrub Baccharis concinna G.M.
           Barroso (Asteraceae)

    • Abstract: ABSTRACT Previous ecological studies of dioecious plant species have found that female plants preferentially occur at lower altitudes where there are typically better nutritional conditions, while male plants often occur in less favorable sites. We compared the ecophysiological performance of male and female plants in three populations of the dioecious Baccharis concinna, an endemic species of rupestrian grasslands of Serra do Cipó, in southeastern Brazil. We hypothesized that physiological differences between the sexes would explain the distribution patterns of the populations. Analyses of the tissue content of phosphorus (P), calcium (Ca), potassium (K) and sodium (Na), and carbon and nitrogen stable isotopes, were used to assess nutritional status and water use efficiency (WUE) in plant leaves, stems and roots of male and female plants in three populations located along an elevational gradient. Differences among populations were related to decreased nutrient levels and WUE at higher elevations, but an effect of sex was found only for %C, with male plants having slightly higher values. In conclusion, the sex ratios in the studied populations of B. concinna could not be attributed to differences in nutrient acquisition and WUE.
  • Habitat heterogeneity and diversity of bryophytes in campos

    • Abstract: ABSTRACT Campos rupestres (rupestrian grasslands) are characterized by the presence of rock outcrops associated with an herbaceous-shrub physiognomy typically growing on quartzitic soils; they occur a wide variety of habitats. Bryophytes respond rapidly and efficiently to variation in microclimate. The present work aimed to study bryophyte species richness, diversity and composition, their life forms, and the substrates they colonize in exposed and shaded habitats in campos rupestres of Chapada Diamantina. Collections were made in 25 x 25 m sampling plots. One hundred and nine species were recorded and included a predominance of mosses (78 spp.) over liverworts (31 spp.). Most species (79 %) were restricted to one of the two types of habitat (exposed versus shaded). While the genera Campylopus, Polytrichum, Schlotheimia, Macromitrium and Syrrhopodon were prevalent in exposed habitats, Sphagnum, Lepidozia, Micropterygium, Bazzania and Odontoschisma prevailed in shaded habitats. The rupicolous community was more prominent than the other communities in both types of habitat. “Weft” was the most frequent life form in shaded areas, while “turf” predominated in exposed sites. The high number of rare, and exclusive, species illustrates the high degree of heterogeneity among bryophyte communities in campos rupestres, and demonstrates the importance of habitat heterogeneity for the high diversity.
  • Does fire determine distinct floristic composition of two Cerrado savanna
           communities on different substrates'

    • Abstract: ABSTRACT We surveyed two savanna sites, one on flat terrain with deep soil (DS), and the other on hilly terrain with rocky outcrops and shallow soil (RS), before and after an accidental fire. We found that the fire did not cause any significant changes in the species composition or diversity of either community, and did not result in floristic homogenization. However, we did record a reduction in the density of plants and in basal area in the DS savanna in comparison with the RS savanna, as well as a higher rate of basal sprouting, which indicates a trade-off between mortality and sprouting. We conclude that, whereas post-fire changes in vegetation structure were more pronounced in the DS savanna than in the RS, the difference in the underlying substrate did not have a direct influence on the post-fire composition of woody species. The greater grass biomass found in the DS savanna in comparison with the RS savanna appears to have been the principal modulator of the severity of the fires in the two phytophysionogmies, and accounts for the distinct responses to fire we observed in the two woody communities.
  • Post-fire resprouting strategies of woody vegetation in the Brazilian

    • Abstract: ABSTRACT Post-fire response by vegetation may reflect the severity of the damage suffered, but we still know little about the species-specific nature of responses to fire or their predictors. Here, we evaluated 26 woody species before and after a fire event in an Cerrado sensu stricto area (typical Brazilian savanna-type) in order to evaluate mortality rates and the type of resprouting (epigeal, hypogeal or epigeal + hypogeal). We evaluated the relative importance of stem diameter, height, and bark thickness as predictors of the type of post-fire resprouting, using a sequential logistic regression model (SLRM). Mortality was 4 %, while epigeal resprouting was recorded in 57 % of the individuals, hypogeal resprouting was recorded in 24 %, and epigeal + hypogeal resprouting in 15 %. Our SLRM analysis indicated that bark thickness, followed by stem diameter, were the best predictors of the type of resprouting. There was a greater than 60 % probability that individuals with bark thicker than 1.6 cm resprouted only epigeally. Our results confirm the resistance (low mortality) and resilience (high resprouting capacity) of the woody vegetation of the Cerrado sensu stricto to fire, and that thick bark is an effective protection against fire damage.
  • Population structure and fruit availability of the babassu palm ( Attalea
           speciosa Mart. ex Spreng) in human-dominated landscapes of the Northeast
           Region of Brazil

    • Abstract: ABSTRACT We studied the population structure and fruit availability of the babassu palm, Attalea speciosa, in three human-dominated landscapes located near a rural community in the region of Araripe, in the Northeast Region of Brazil, that were under intense fruit harvest. Fifty 10 x 10 m plots were randomly established in each of the three landscapes, and all individuals of A. speciosa within the plots were classified as seedlings, juveniles or adults, with the height of all adult individuals being measured. An additional 20 individuals were marked in each landscape, and the number of total bunches, fruits per bunch and bunches per palm tree were recorded. The populations of A. speciosa in the three landscapes exhibited an inverted J-shape plot, but pasture and shifting cultivation possessed a significantly higher number of individuals, seedlings and adults than the seasonal semideciduous forest, plus they possessed a greater seedling/adult ratio. Shifting cultivation was found to be favorable for fructification. The present study found that shifting cultivation and pastures are landscape practices that can contribute to the rapid expansion and establishment of A. speciosa, which can become a dominant species in the region of Araripe.
  • Urban ethnobotany: a case study in neighborhoods of different ages in
           Chapecó, Santa Catarina State

    • Abstract: ABSTRACT The study of urban home gardens is still a current gap in knowledge in Brazilian ethnobotany researches, especially in the south of Brazil. This study was carried out to survey the species composition of plants in urban residential home gardens of two neighborhoods in the municipality of Chapecó (state of Santa Catarina, southern Brazil): an older neighborhood created prior to the 1950s, and a younger neighborhood created in the decade 1970-1980. It was hypothesized that the home gardens in the older neighborhood would be larger and have greater species richness than those in the younger neighborhood. Data from 10 home gardens in each neighborhood were collected through semi-structured interviews. The plants cited by interviewees were classified as used for alimentary, medicinal and/or ornamental purposes. A total of 372 plant species (256 in the older neighborhood and 248 in the younger one) were recorded. The two neighborhoods differed in the size of their home gardens, but had similar species richness. The high species richness of plants cultivated for alimentary, medicinal and ornamental purposes in both Chapecó neighborhoods indicates that these spaces are an important resource for food, subsistence and well-being.
  • Patterns of growth, development and herbivory of Palicourea rigida are
           affected more by sun/shade conditions than by Cerrado phytophysiognomy

    • Abstract: ABSTRACT Plant development is influenced by several abiotic factors, which in turn influence morphological traits and life history. We investigated whether leaf area, herbivory, toughness, fluctuating asymmetry, structural complexity and the number of inflorescences of Palicourea rigida are influenced by sun/shade conditions or by Cerrado phytophysiognomy (typical cerrado or rupestrian field). We expected to find greater structural complexity, leaf toughness and more inflorescences in sun plants; shaded plants were expected to exhibit a greater degree of fluctuating asymmetry (an index of plant stress), reduced leaf toughness and greater herbivory. As for phytophysiognomies, we expected to find higher levels of leaf toughness and reduced structural complexity in plants from the rupestrian field. We sampled plants in the sun and shade from both phytophysiognomies. Leaf area, toughness, herbivory and fluctuating asymmetry, were influenced more by sun/shade conditions than phytophysiognomy; leaf toughness was the only variable to show greater values in conditions of sun. Our results indicate that exposure to sunlight is not a requirement for increased plant development, but plants in shade are experiencing stress, as shown by increased fluctuating asymmetry; increased leaf area, which is a strategy to compensate for lower light exposure for plants and higher herbivory, which depicts lower toughness.
  • Arbuscular mycorrhizal fungi and dark septate fungi in plants associated
           with aquatic environments

    • Abstract: ABSTRACT There have been several reports of symbionts in the roots of plants that live in aquatic environments. Arbuscular mycorrhizal fungi (AMF) are the most common microsymbionts and possibly recolonized the aquatic environment together with plants; however, their functions and the extent of their benefits are unclear. Furthermore, the presence of other groups of fungi, such as dark septate fungi (DSF), with functions supposedly analogous to those of mycorrhizal fungi, has also been reported. The present work provides a compilation of data regarding the presence of arbuscular mycorrhizae in plants from, or under the influence of, aquatic environments, and co-colonization by AMF and DSF. Forty species of non-vascular plants, ferns, fern allies, and gymnosperms from 15 families, and 659 species of angiosperms from 87 families were investigated. From the first group (non-flowering plants) 57 % of the species showed arbuscular mycorrhizal structures in their tissues or roots, whereas among the second group (flowering plants) 71% had such structures. Among the mycorrhizal angiosperms, 52 % showed arbuscules in their roots. DSF were found in 1% of non-flowering plants and 5 % of angiosperms. All of these are discussed in this review.
  • Updating the list of chromosome numbers for Philodendron

    • Abstract: ABSTRACT Aiming for a better understanding of karyotype evolution within Philodendron, we report chromosome counts for 23 species of the genus, of which 19 are being reported for the first time, thus increasing to 84 ( ca. 17 % of the genus) the total number of species with available chromosome counts. The diploid numbers 2 n = 32 and 2 n = 34 were the most common, with 10 and 11 species, respectively, whereas only two species presented different chromosome numbers ( P. giganteum with 2 n = 30 and P. adamantinum with 2 n = 36). The results are discussed in the context of previous analyses of karyotypes of Philodendron spp., taking into account bidirectional dysploidy as the main mechanism of chromosome number evolution within the genus.
  • Spore germination and young gametophyte development of the endemic
           Brazilian hornwort Notothylas vitalii Udar & Singh (Notothyladaceae -
           Anthocerotophyta), with insights into sporeling evolution

    • Abstract: ABSTRACT Notothylas vitalii is an endemic Brazilian hornwort species, easily identified by the absence of pseudoelaters and columella, and the presence of yellow spores. Plant material was collected in Recife, Brazil, and the spores were sown onto Knop’s medium, germinating after thirty days only with the presence of light. Germination occurred outside the exospore, and only after the walls had separated into three or four sections did a globose sporeling initiate its development. Following longitudinal and transversal divisions, the initial loose mass of cells became a thalloid gametophyte, subsequently developing into a rosette-like juvenile thallus with flattened lobes. Additional information concerning sporeling types in key genera of hornworts, such as Folioceros and Phymatoceros, will be crucial for inferring the possible ancestral type and the evolution of this trait among hornworts. Our study supports the necessity of supplementary studies on sporeling development, combined with morphological and phylogenetic investigations, to help elucidate the evolution of the Anthocerotophyta and their distribution patterns.
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Heriot-Watt University
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