144 research outputs found

    Tribu LYCIEAE Hunz.

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    Se describe la familia Solanaceae y se presenta una clave con los generos presentes en la provincia (en coautoria con G. Barboza y F. Chiarini). Asimismo, y de mi autoria, se tratan los dos géneros de la Tribu Lycieae y la descripcion de las especies autóctonas de la provincia de Mendoza.Fil: Bernardello, Gabriel Luis Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Instituto Multidisciplinario de Biología Vegetal (p); Argentina; Argentin

    Nectaries and reproductive biology of croton sarcopetalus (euphorbiaceae)

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    Flower morphology, nectary structure, nectar chemical composition, breeding system, floral visitors and pollination were analysed in Croton sarcopetalus, a diclinous-monoecious shrub from Argentina. Male flowers have five receptacular nectaries, with no special vascular bundles, that consist of a uniserial epidermis with stomata subtended by a secretory parenchyma. Female flowers bear two different types of nectaries: inner (IN) and outer (ON) floral nectaries. IN, five in all, are structurally similar to the nectaries of male flowers. The five ON are vascularized, stalked, and composed of secretory, column-shaped epidermal cells without stomata subtended by secretory and ground parenchyma. In addition, ON act as post-floral nectaries secreting nectar during fruit ripening. Extrafloral nectaries (EFN) are located on petioles, stipules and leaf margins. Petiolar EFN are patelliform, stalked and anatomically similar to the ON of the female flower. Nectar sampled from all nectary types is hexose dominant, except for the ON of the female flower at the post-floral stage that is sucrose dominant. The species is self-compatible, but geitonogamous fertilization is rarely possible because male and female flowers are not usually open at the same time in the same individual, i.e. there is temporal dioecism. Flowers are visited by 22 insect species, wasps being the most important group of pollinators. No significant differences were found in fruit and seed set between natural and hand pollinated flowers. This pattern indicates that fruit production in this species is not pollen/pollinator limited and is mediated by a wide array of pollinators. © 2001 The Linnean Society of London.Fil: Freitas, Leandro. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Bernardello, Gabriel Luis Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Galetto, Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Paoli, Adelita. Universidade Estadual Paulista Julio de Mesquita Filho; Brasi

    Floral nectaries, nectar production dynamics, and chemical composition in six Ipomoea species (Convulvulaceae) in relation to pollinators

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    Background and Aims Floral nectaries and nectar features were compared between six Argentinian Ipomoea species with differences in their pollinator guilds: I. alba, I. rubriflora, I. cairica, I. hieronymi var. hieronymi, I. indica, and I. purpurea. • Methods Pollinators were recorded in natural populations. The morpho-anatomical study was carried out through scanning electron and light microscopy. Nectar sugars were identified via gas chromatography. Nectar production and the effect of its removal on total nectar sugar amount were determined by using sets of bagged flowers. • Key Results Hymenopterans were visitors of most species, while hummingbirds visited I. rubriflora and sphingids I. alba. All the species had a vascularized discoidal nectary surrounding the ovary base with numerous open stomata with a species-specific distribution. All nectar samples contained amino acids and sugars. Most species had sucrose-dominant nectars. Flowers lasted a few hours. Mean nectar sugar concentration throughout the lifetime of the flower ranged from 34·28 to 39·42 %, except for I. cairica (49·25 %) and I. rubriflora (25·18 %). Ipomoea alba had the highest nectar volume secreted per flower (50·12 µL), while in the other taxa it ranged from 2·42 to 12·00 µL. Nectar secretion began as soon as the flowers opened and lasted for a few hours (in I. purpurea, I. rubriflora) or it was continuous during the lifetime of the flower (in the remaining species). There was an increase of total sugar production after removals in I. cairica, I. indica and I. purpurea, whereas in I. alba and I. rubriflora removals had no effect, and in I. hieronymi there was a decrease in total sugar production. • Conclusions The chemical composition, production dynamics and removal effects of nectar could not be related to the pollinator guild of these species. Flower length was correlated with nectary size and total volume of nectar secreted, suggesting that structural constraints may play a major role in the determination of nectar traits of these species.Fil: Galetto, Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Bernardello, Gabriel Luis Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentin

    Floral nectaries, nectar production dynamics, and chemical composition in six Ipomoea species (Convulvulaceae) in relation to pollinators

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    Background and Aims Floral nectaries and nectar features were compared between six Argentinian Ipomoea species with differences in their pollinator guilds: I. alba, I. rubriflora, I. cairica, I. hieronymi var. hieronymi, I. indica, and I. purpurea. • Methods Pollinators were recorded in natural populations. The morpho-anatomical study was carried out through scanning electron and light microscopy. Nectar sugars were identified via gas chromatography. Nectar production and the effect of its removal on total nectar sugar amount were determined by using sets of bagged flowers. • Key Results Hymenopterans were visitors of most species, while hummingbirds visited I. rubriflora and sphingids I. alba. All the species had a vascularized discoidal nectary surrounding the ovary base with numerous open stomata with a species-specific distribution. All nectar samples contained amino acids and sugars. Most species had sucrose-dominant nectars. Flowers lasted a few hours. Mean nectar sugar concentration throughout the lifetime of the flower ranged from 34·28 to 39·42 %, except for I. cairica (49·25 %) and I. rubriflora (25·18 %). Ipomoea alba had the highest nectar volume secreted per flower (50·12 µL), while in the other taxa it ranged from 2·42 to 12·00 µL. Nectar secretion began as soon as the flowers opened and lasted for a few hours (in I. purpurea, I. rubriflora) or it was continuous during the lifetime of the flower (in the remaining species). There was an increase of total sugar production after removals in I. cairica, I. indica and I. purpurea, whereas in I. alba and I. rubriflora removals had no effect, and in I. hieronymi there was a decrease in total sugar production. • Conclusions The chemical composition, production dynamics and removal effects of nectar could not be related to the pollinator guild of these species. Flower length was correlated with nectary size and total volume of nectar secreted, suggesting that structural constraints may play a major role in the determination of nectar traits of these species.Fil: Galetto, Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Bernardello, Gabriel Luis Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentin

    Anatomía floral de dos especies de Larnax (Solanaceae)

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    Se estudia comparativamente la anatomía floral de dos especies peruanas del género Larnax Miers (tribu Solaneae): L. lutea S. Leiva y L. parviflora N. W. Sawyer & S. Leiva, con especial referencia a la vasculatura floral. Los datos obtenidos son novedosos a nivel genérico. Dentro de las características importantes a este nivel se destacan la presencia de cáliz acrescente, petalostemo y nectario ovárico. Se analiza el valor de los datos obtenidos en la delimitación de Larnax con géneros afines, concluyéndose que es más cercano a Athenaea y Aureliana que a Deprea, lo cual apoya el reciente nuevo sistema de Hunziker (2001).The floral anatomy of two Peruvian species of the genus Larnax Miers (tribe Solaneae) is studied: L. lutea S. Leiva and L. parviflora N. W. Sawyer & S. Leiva, with emphasis on their floral vasculature. The obtained results are new at the generic level. Among the most important features for the genus, are mentioned the presence of an accrescent calyx, the stapet, and an ovarian nectary. These data are analyzed in the delimitation of Larnax with allied genera, reaching the conclusion that it is closer to Athenaea and Aureliana than is to Deprea, supporting the recent system proposed by Hunziker (2001).Fil: Cabrera, Mario Fernando. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; ArgentinaFil: Bernardello, Gabriel Luis Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentin

    On the causes of the differential seed production in the anficarpic species Trifolium polymorphum (Leguminosae)

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    Trifolium polymorphum es una leguminosa de pradera con buena adaptación y persistenciaen este tipo de vegetación. Combina diferentes estrategias reproductivas como la reproducción vegetativa por estolones y la reproducción por semillas producidas en dos tipos de frutos y flores, subterráneas y aéreas. Las subterráneas son cleistógamas y las aéreas son casmógamas. Empíricamente se ha detectado mayor formación de semillas en los frutos subterráneos que en los aéreos. En el presente trabajo se realizan estudios embriológicos y de desarrollo de semillas en ambos tipos de flores para dilucidar si existen causas ontogenéticas que determinan la productividad diferencial de semillas en ambos tipos de frutos. No se detectaron causas embriológicas pre-cigóticas que expliquen el menor número de semillas en los frutos de las flores aéreas. Ambos tipos de semillas comparten características ontogenéticas y presentan apropiado desarrollo de los óvulos, sacos embrionarios y establecimiento de vías nutricionales para saco  embrionario, embrión y endosperma. En general las floraciones insumen un costo energético importante para las especies vegetales. La floración aérea de T. polymorphum, aunque sometida a una fuerte presión de herbivoría del ganado, incorpora variabilidad genética a sus poblaciones a través de la polinización cruzada y permite la dispersión a distancia.Trifolium polymorphum is recognized as one of the best adapted legume in field conditions. It combines different reproductive strategies such as stoloniferous vegetative reproduction and seed reproduction by two types of fruits produced in underground and aerial flowers. These last ones are chasmogamous and underground flowers are cleistogamous. A higher seed production has empirically been detected in underground flowers rather than in aerial ones. In the present work, embryological studies in aerial and underground flowers were carried out in order to determine the existence of ontogenetic causes which may promote productivity differences in both types of seeds. No embryological pre-zygotic cause explaining aerial flowers low productivity was detected. Aerial and underground seeds share ontogenetic characteristics as both types of flowers showed normal ovule and embryo sac development. Similar nutritional pathways for embryo sacs, embryos and endosperms were also observed. In general, flowering represents a high energetic inversion for plant species. Aerial flowering in T. polymorphum, though subjected to a strong herbivorous pressure, incorporates genetic variability to populations through cross-pollination and succeeds in facilitating long distance dispersion.Fil: Speroni, Gabriela. Universidad de la República. Facultad de Agronomía. Dpto. Biología Vegetal. Laboratorio de Botánica; UruguayFil: Izaguirre, Primavera. Universidad de la República. Facultad de Agronomía. Dpto. Biología Vegetal. Laboratorio de Botánica; UruguayFil: Bernardello, Gabriel Luis Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Instituto Multidisciplinario de Biología Vegetal (p); Argentina; Argentina. Universidad Nacional de Córdoba; Argentin

    La Biotechnologie dans les manuels secondaires: un étude des manuels utilisés à Cordoba (Argentine)

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    Este trabajo tiene por objetivo caracterizar cómo se aborda la biotecnología en los libros de texto utilizados en escuelas secundarias de la ciudad de Córdoba (Argentina). Para ello se emplea una metodología centrada en el análisis de contenido que combina técnicas e instrumentos cuanticualitativos. La muestra comprende 12 libros de texto de biología los cuales fueron seleccionados a partir de la información recolectada a través de entrevistas a ocho docentes. Los aspectos analizados son: temas de biología en los que se presenta a la biotecnología en los libros de texto, contenidos desarrollados, formatos (texto, ilustraciones y actividades) utilizados, jerarquía textual y profundidad con la cual se presenta a los contenidos y, por último, elementos contextuales incluidos. A partir de los resultados obtenidos se destaca que son escasos los contenidos de biotecnología que se desarrollan de manera profunda en los libros. En su mayoría, éstos se encuentran en lecturas complementarias, fuera del texto principal del capítulo, y se incluyen pocos elementos contextuales. Estas deficiencias ponen en evidencia la necesidad de elaborar libros de texto y materiales curriculares, tanto en soporte papel como digital, que permitan dar una respuesta ante la situación actual de los libros de texto.This work attempts to characterize the way in which secondary textbooks in Cordoba, Argentina, present biotechnology topics. The methodology used is content analysis, from which quantitative and qualitative techniques and instruments are combined. The sample includes twelve biology textbooks, which were selected considering the information collected by interviews to eight teachers. The aspects analyzed are: in what biology topics is biotechnology presented in textbooks; what contents are developed; what formats (text, images and activities) are used; in what textual hierarchy and how deep are the contents presented; and, finally, what contextual elements are included. The results obtained indicate that few biotechnology contents are developed in textbooks in any depth. Most biotechnology contents are included in complementary readings outside the main text used for a chapter, and few contextual elements are provided. These shortcomings point out the need to make printed and digital textbooks and curricular materials that give a response to the current situation of textbooks.Ce travail caractérise comment la biotechnologie est discuté dans les manuels utilisés dans les écoles secondaires de la ville de Córdoba (Argentine). La méthodologie utilisée est l'analyse de contenu, en combinant des techniques et outils quantitatives et qualitatives. L'échantillon est de 12 manuels de biologie et les aspects analysés sont: les sujets de biologie présentées à la biotechnologie dans les manuels scolaires, quel contenus sont développés, quel formats (texte, illustrations, et activités) sont utilisés, dans quelle hiérarchie textuelle et à quel point le contenu est présenté et, enfin, quels éléments contextuels sont inclus. D'après les résultats mis en évidence, il y a peu de contenus de la biotechnologie dans les manuels, ces contenues ne son pas développés en profondeur dans les livres, la plupart d'entre eux sont en lectures en dehors du texte principal, et peux éléments contextuels sont inclus. Ces lacunes mettent en évidence la nécessité pour les manuels scolaires et du matériel pédagogique, en papier et digital, permettant de répondre à la situation actuelle des manuels scolaires.Fil: Occelli, Maricel. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Instituto Multidisciplinario de Biología Vegetal (p); ArgentinaFil: Valeiras, Nora. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; ArgentinaFil: Bernardello, Gabriel Luis Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Instituto Multidisciplinario de Biología Vegetal (p); Argentina. Universidad Nacional de Córdoba; Argentin

    Reproductive biology, seed germination and regeneration of Flourensia DC. species endemic to Central Argentina (Asteraceae)

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    Our objective was to study reproductive biology, seed germination and regeneration, through morphoanatomical and field observations and controlled experiments, to assess reproductive strategies in six rare Flourensia endemic to Central Argentina (F. campestris, F. hirta, F. leptopoda, F. niederleinii, F. oolepis, F. tortuosa). Structure of capitula, flowers, and achenes was described. Capitula were visited by a variety of insects. Achenes required 30-45 days to mature. Fruit set varied significantly among species. Flourensia campestris and F. oolepis were self-incompatible. Seed viability decreased after 19 months and was lost after 32 months. Flourensia oolepis and F. campestris had the highest germination percentages (>60%); the addition of gibberellic acid in 2-months old seeds did not influence germination. The remaining species had lower germination percentages (<30%). All species had xylopodia that were root and stem modifications. Burned individuals of F. campestris actively regenerated from underground buds of xylopodia, being suitable for restoration of degraded or burned areas. Flourensia campestris and F. oolepis had better reproductive success, but the remainder species can be considered at risk. Strategies should be implemented to protect them, such as to preserve its habitat together with attempts to increase their population sizes and maintain their pollinators.Fil: Delbón, Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Cosa, María Teresa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Bernardello, Gabriel Luis Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentin

    Acnistus arborescens (Solanaceae): An important food resource for birds in an Atlantic Forest site, Southeastern Brazil

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    Biotic interactions related to the consumption of floral nectar and fruits as food resource by birds promoting plant pollination and dispersal, are essential for forest ecosystem functioning. The daily interaction of birds with Acnistus arborescens (L.) Schltdl. (Solanaceae), a shrub-tree, was studied in the Itatiaia National Park and its surroundings. Reproductive phenology was monthly monitored in eighteen individuals in 2015. During flowering (August to November) and fruiting (September to December) the interaction birds-plant was studied. Flowers were visited by seven hummingbird species and several insects. Fruit set was 87.3%. Thirty-five bird species of eleven families consumed its fruit. Thraupidae with sixteen bird species was the family responsible for most of its frugivory (53.9%). Considering that more than 10% of the birds richness of Itatiaia National Park INP interacts with A. arborescens, it can be considered an important plant species in maintaining local bird diverstity. Thus, for attracting many birds, A. arborescens can be used in the process of recovery of degraded areas, and also as a focal plant species for environmental education programs and birdwatching.Fil: Azimoff, Izar. jInstituto de Pesquisas Jardim Botânico do Rio de Janeiro; BrasilFil: Soares, Hudson Martins. Universidade do Estado de Rio do Janeiro; BrasilFil: Bernardello, Gabriel Luis Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentin

    A new generic circumscription in tribe Lycieae (Solanaceae)

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    Tribe Lycieae (Solanaceae) currently includes ca. 92 species in three genera. Two genera account for only a few species, as Phrodus is monotypic and Grabowskia includes just four species. By contrast, Lycium is one of the largest genera in the family, with ca. 88 species and over 95% of the species diversity in tribe Lycieae. Previous molecular studies have suggested that Lycium is paraphyletic and that species of Grabowskia are nested within Lycium. These studies also suggested that the genus Grabowskia was monophyletic, but questioned the integrity of species within it. Likewise, although the genus is defined by a unique fruit structure, morphology is of limited use in distinguishing species within Grabowskia. Depending on the study, Phrodus microphyllus has been placed either as sister to the rest of the tribe or nested within Lycium. In the present study we include data from two nuclear regions (granule-bound starch synthase and nitrate reductase) and four plastid spacer regions (trnH-pbsA, trnDGUC-trnT  GGU, rpl32-trnLUAG, ndhF-rpl32) to more clearly resolve evolutionary relationships among genera within the tribe and among species in Grabowskia. Results confirm that Lycium is paraphyletic and includes a monophyletic Grabowskia. However, inclusion of multiple accessions of several Grabowskia species does not support the maintenance of distinct species in the genus. In addition, Phrodus microphyllus is moderately supported as basal within the tribe. Given these results, which are further strengthened by morphological and cytological data, we synonymize three Grabowskia species with Grabowskia boerhaviifolia and include this species within Lycium, using its basionym, Lycium boerhaviifolium L.f. Additionally, we transfer Phrodus microphyllus to the genus Lycium, proposing a new combination: Lycium bridgesii (Miers) Levin, Miller & Bernardello. Tribe Lycieae is now monotypic, including the single genus Lycium.Fil: Levin, Rachel. Amherst College. Department of Biology; Estados UnidosFil: Bernardello, Gabriel Luis Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Instituto Multidisciplinario de Biología Vegetal (p); ArgentinaFil: Whiting, Carolyn. Amherst College. Department of Biology; ArgentinaFil: Miller, Jill. Amherst College. Department of Biology; Estados Unido
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