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- Local factors have a greater influence on the abundance of alfalfa weevil and its larval parasitoids than landscape complexity in heterogeneous landscapesPublication . Levi‑Mourao, A.; Meseguer, R.; Madeira, Filipe; Martinez‑Casasnovas, J.A.; Costamagna, A.C.; Pons, X.Context The alfalfa weevil Hypera postica Gyllenhal (Coleoptera: Curculionidae) is one of the most destructive pests of alfalfa worldwide. Both local and landscape-scale factors can significantly infuence crop pests, natural enemies, and the efectiveness of biological control services, but the relative infuence of these factors is unclear. Objectives We investigated the infuence of the local variables and surrounding landscape composition and configuration on the abundance of alfalfa weevil, and on the abundance and parasitism rates of its larval parasitoids, Bathyplectes spp. Methods We sampled 65 commercial alfalfa fields along the Ebro Basin, Spain, over a period of 3 years, recording the field characteristics and landscape structure at three buffer radii of 250, 500 and 1000 m from the center of each field. Results The abundance of weevil larvae was positively associated with the field perimeter and with the uncut alfalfa surrounding the pipes of the sprinkler irrigation system, but only one configuration variable was positively correlated: the alfalfa edge density. No local characteristics or landscape structures were associated with the abundance of adult weevils. The abundance of Bathyplectes spp. adults was positively associated to local factors such as the densities of alfalfa weevils and aphids. Few landscape structure variables, such as alfalfa edge density and Simpson’s Diversity Index, had explanatory value only at 250 m buffer radius. The rate of larval parasitism was affected by local variables, such as alfalfa weevil abundance and field age. Conclusion Our results provide, for the first time in the Mediterranean region and Europe, evidence of the relative importance of landscape structure and local factors on the abundance of the alfalfa weevil and its larval parasitoids, Bathyplectes spp. The strongest infuences were based on local characteristics.
- Nutritive value and condensed tannins of tree legumes in silvopasture systemsPublication . Silva, I.A.G.; Dubeux Jr., J.C.B.; Souza, Carla G.; Moreno, M.R.; Santos, M.V.F.; Apolinário, V.X.O.; Mello, A.C.L.; Cunha, M.V.; Muir, J.P.; Junior, M.A.L.Introducing legumes into C4-dominated tropical pastures, may enhance their sustainability but has some pasture management constraints. One potential alternative is using arboreal legumes, but several of these species have relatively high condensed tannin (CT) concentrations, which negatively impact forage quality. There is limited knowledge, however, on how arboreal legume leaf CT content varies over the year and how this might impact forage quality. The objective of this 2 year study was to assess the seasonal variation of CT and nutritive value for ruminants of the tropical tree legumes gliricidia [Gliricidia sepium (Jacq.) Kunth ex. Walp.] and mimosa (Mimosa caesalpiniifolia Benth). The research was carried out in the sub-humid tropical region of Brazil on well-established pastures in which either legume was present with signalgrass (Urochloa decumbens Stapf.). We determined CT and nitrogen concentrations, in vitro digestible organic matter (IVDOM), and leaf δ13C and δ15N from January to October of 2017 and 2018. All parameters were afected (P< 0.05) by the interaction between legume species and sampling time, with generally higher leaf CT content for mimosa than gliricidia, and both were reduced at the start of the dry season, although much more drastically for mimosa. The IVDOM was strongly afected by CT content and increased at the start of the dry season, coincidentally when C4 grass forage quality typically decreased. There is a marked species efect, with CT from gliricidia impacting IVDOM more than the same CT content from mimosa. While N concentration from mimosa also increased at the start of the dry season, that for gliricidia did not vary over the year. We conclude that although these arboreal legumes have relatively high CT contents, these reduce during the dry season when CT concentrations coinciding with a reduced forage quality as the protein content for C4 grasses is usually inadequate in this season.
- Análise da coordenação motora da marcha em idoso com artroplastia total do joelho: estudo de casoPublication . Tavares, Bárbara; Leal, Inês; Mercê, Cristiana; Branco, Marco A. C.A avaliação da marcha é um fator crucial na medição dos resultados pós-operatório da Artroplastia Total do Joelho. A Artroplastia Total do Joelho (ATJ) é uma opção cirúrgica destinada a pacientes com estágios avançados de degeneração articular no joelho. O objetivo deste estudo consistiu em avaliar as assimetrias na coordenação motora na marcha de um indivíduo idoso com ATJ. O participante, com 68 anos e do sexo masculino, realizou uma única sessão de marcha onde foram captados os dados do giroscópio, através da aplicação Phyphox. O tratamento de dados foi realizado no Microsoft Excel. Através da análise da fluidez e dispersão das linhas, os resultados evidenciaram que entre os vários planos, o plano sagital apresentou a melhor coordenação motora. Verificou-se ainda uma menor rotação externa do membro inferior submetido a ATJ. De acordo com os resultados e, de forma a reduzir as assimetrias identificadas, recomenda-se que o participante realize exercícios de reforço muscular e propriocepção.