301 research outputs found

    Nidification of Polybia platycephala and Polistes versicolor (Hymenoptera: Vespidae) on Plants of Musa spp. In Minas Gerais State, Brazil

    Get PDF
    Social wasps are natural enemies of caterpillars and, therefore, they have potential to control insect pests in various crops. Three colonies of Polybia platycephala (Richards) and one of Polistes versicolor (Olivier) (Hymenoptera: Vespidae) were found on plants of banana (Musa spp.) in Minas Gerais State, Brazil. These colonies were at 3.50 m high, under the leaves, which provide shelter from environmental stress

    Major shifts at the range edge of marine forests: the combined effects of climate changes and limited dispersal

    Get PDF
    Global climate change is likely to constrain low latitude range edges across many taxa and habitats. Such is the case for NE Atlantic marine macroalgal forests, important ecosystems whose main structuring species is the annual kelp Saccorhiza polyschides. We coupled ecological niche modelling with simulations of potential dispersal and delayed development stages to infer the major forces shaping range edges and to predict their dynamics. Models indicated that the southern limit is set by high winter temperatures above the physiological tolerance of overwintering microscopic stages and reduced upwelling during recruitment. The best range predictions were achieved assuming low spatial dispersal (5 km) and delayed stages up to two years (temporal dispersal). Reconstructing distributions through time indicated losses of similar to 30% from 1986 to 2014, restricting S. polyschides to upwelling regions at the southern edge. Future predictions further restrict populations to a unique refugium in northwestern Iberia. Losses were dependent on the emissions scenario, with the most drastic one shifting similar to 38% of the current distribution by 2100. Such distributional changes might not be rescued by dispersal in space or time (as shown for the recent past) and are expected to drive major biodiversity loss and changes in ecosystem functioning.Electricity of Portugal (Fundo EDP para a Biodiversidade); FCT - Portuguese Science Foundation [PTDC/MAR-EST/6053/2014, EXTANT-EXCL/AAG-GLO/0661/2012, SFRH/BPD/111003/2015

    Attack behavior of Podisus rostralis (Heteroptera: pentatomidade) adults on caterpillars of Bombyx mori (Lepidoptera: bombycidae).

    Get PDF
    Estudou-se, em laboratório, o comportamento de ataque de adultos do predador Podisus rostralis (Stäl) (Heteroptera: Pentatomidae) tendo como presa lagartas de quarto estádio de Bombyx mori L. (Lepidoptera: Bombycidae). Dez adultos do predador, com 24 horas de idade, foram observados durante duas horas acompanhando-se os seguintes comportamentos de ataque: (1) Predador: localização da presa; observação da presa; toque das presas com as antenas; comportamento de ataque; paralisação da presa; fuga do predador após ataque; finalização do ataque; ataques sucessivos; e (2) Presa: defesa. O predador P. rostralis localizou sua presa antes do ataque, aproximando-se dela através de lentos movimentos circulares. O ataque é, usualmente, realizado na parte posterior da presa para reduzir reação de defesa. O maior tamanho da presa em relação ao predador pode dificultar a paralisação, porém o predador consegue paralisá-la em menos de duas horas

    Produtividade estacional, melhoramento e manejo de pastagens na Ilha de Marajó.

    Get PDF
    bitstream/item/57747/1/CPATU-ComTec51.pd

    Melhoramento e manejo de pastagens na Ilha de Marajó: resultados e informações práticas.

    Get PDF
    bitstream/item/60052/1/Miscelanea-6.pd

    Development of antennal sensilla of Tetragonisca angustula Latreille, 1811 (Hymenoptera: Meliponini) during pupation

    Get PDF
    The antennal sensilla are sensory organs formed by a group of neurons and accessory cells, which allow perception of environmental cues, which play a role as mechanoreceptors and chemoreceptors. This study describes the post-embryonic development of the antennal sensilla of the stingless Tetragonisca angustula (Hymenoptera: Meliponini) workers. The development of the antennal sensilla begins in the transition stage of the pre-pupae to white-eyed pupae. The sensilla are completely developed at the black-eyed pupae stage, but they are covered by the old cuticle. The sensilla are exposed to the environment only in newly emerged workers of T. angustula, but it is possible that environmental stimuli can be recognized due to the pores in the old cuticle.As sensilas antenais são órgãos sensoriais formados por um conjunto de neurônios que captam estímulos ambientais e células acessórias, desempenhando as funções de mecanorreceptores e quimiorrecepterores. Este trabalho descreve o desenvolvimento pós-embrionário das sensilas antenais de operárias das abelhas sem ferrão Tetragonisca angustula (Hymenoptera: Meliponini). O desenvolvimento das sensilas tem início na transição de pré-pupa para pupa de olho branco e estão completamente desenvolvidas no estágio de pupa de olho preto, mas ainda estão cobertas pela cutícula velha. As sensilas estão completamente expostas em operárias recém-emergidas de T. angustula, mas é possível que estímulos ambientais sejam percebidos em estágios anteriores devido aos poros presentes na cutícula velha

    Canarana erecta lisa Echinochloa pyramidalis (Lam.) Hitchc. et Chase.

    Get PDF
    bitstream/item/69745/1/IPEAN-Forrageiras1.pd
    corecore