15 research outputs found
Trailing Boom on Fungicides Application on Wheat, Bean and Soybean
This study aimed to determine the influence of air-assisted and trailing boom technologies on fungicide applications to control diseases incidence and severity on wheat, bean and soybean. The experiments were conducted in three different sites in the Campos Gerais (PR) region in a completely randomized blocks design. In the wheat crop season of 2011, the treatments were: i) control (no fungicide application on the plants); fungicide spray with ii) nozzles in conventional ground boom sprayer; iii) nozzles in trailing boom; and iv) nozzles in conventional boom sprayer + trailing boom simultaneously. In the bean and soybean crop season of 2011-12, we added an extra treatment of boom with air-assisted sprayer, since the farmers had this technology available. We conclude that at the area under the disease progress curve (AUDPC), the diseases controlled with fungicides presented lower severity and incidence compared with the control treatment for all the crops evaluated. The fungicide spraying technology aggregated to air-assisted and trailing boom did not differ from the conventional boom sprayer for disease control and yield components of wheat, beans and soybeans
Submarine volcanic morphology of the western Galapagos based on EM300 bathymetry and MR1 side-scan sonar
Author Posting. © American Geophysical Union, 2007. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geochemistry Geophysics Geosystems 8 (2007): Q03010, doi:10.1029/2006GC001464.A compilation of high-resolution EM300 multibeam bathymetric and existing MR1 side-scan sonar data was used to investigate the volcanic morphology of the flanks of the western Galápagos Islands. The data portray an assortment of constructional volcanic features on the shallow to deep submarine flanks of Fernandina, Isabela, and Santiago Islands, including rift zones and groups of cones that are considered to be the primary elements in constructing the archipelagic apron. Ten submarine rift zones were mapped, ranging in length from 5 to 20 km, comparable in length to western Canary Island rift zones but significantly shorter than Hawaiian submarine rift zones. A detailed analysis of the northwestern Fernandina submarine rift, including calculated magnetization from a surface-towed magnetic study, suggests that the most recent volcanism has focused at the shallow end of the rift. Small submarine volcanic cones with various morphologies (e.g., pointed, cratered, and occasionally breached) are common in the submarine western Galápagos both on rift zones and on the island flanks where no rifts are present. At depths greater than ∼3000 m, large lava flow fields in regions of low bathymetric relief have been previously identified as a common seafloor feature in the western Galápagos by Geist et al. (2006); however, their source(s) remained enigmatic. The new EM300 data show that a number of the deep lava flows originate from small cones along the mid-lower portion of the NW submarine rift of Fernandina, suggesting that the deep flows owe their origin, at least in part, to submarine rift zone volcanism.Data collected on TN188
was funded by NSF grant OCE0326148 and NOAA grant
NA04OAR460009 to S.M.W. Support for data collected on
previous multibeam and MR1 cruises was provided by NSF
grants OCE9811504 and OCE0002461 (D.J.F.)
Semeadura do milho em sistema de plantio direto sem e com manejo mecânico da matéria seca
Semeadura do milho em sistema de plantio direto sem e com manejo mecânico da matéria seca
O objetivo deste trabalho foi verificar se a cultura do milho é influenciada pelo manejo mecânico da aveia-preta dessecada antes de sua semeadura, pela utilização de rolo destorroador. Os tratamentos consistiram na semeadura do milho sob a matéria seca de aveia-preta dessecada sem manejo mecânico e rolada. O experimento foi realizado em quatro propriedades, duas na safra de 2007/2008 e as outras duas na safra de 2008/2009. O delineamento experimental adotado foi em blocos ao acaso, com 11 repetições, cujas parcelas possuíam 80 m² cada. Avaliaram-se a qualidade da semeadura e os componentes de rendimento. Conclui-se que o manejo mecânico da palha de aveia-preta antes da semeadura do milho pode elevar significativamente os espaçamentos falhos e reduzir significativamente os espaçamentos aceitáveis. Nas áreas experimentais, os tratamentos não afetaram os componentes de rendimento da cultura do milho, havendo apenas acréscimo no custo da produção
Influência da velocidade de deslocamento na semeadura do milho Influence of speed increasing in corn seeding
Teve-se o objetivo de verificar a influência da velocidade de deslocamento na semeadura de milho, variando de 3,0 a 9,0 km h-1, em quatro condições. As variáveis analisadas foram: população de plantas emergidas, distribuição longitudinal, população com espigas e os componentes de rendimento. Concluiu-se que há aumento na percentagem de espaçamentos falhos e múltiplos e queda de espaçamentos aceitáveis ao se elevar a velocidade de semeadura. A produtividade só foi afetada quando a população de plantas com espigas foi reduzida pelo incremento de velocidade.<br>The aim of this study was to assess the influence of planter travel speed in corn seeding, between 3.0 and 9.0 km h-1, in four different locations. The variables analyzed were: population of emerged plants, longitudinal distribution, population of plants bearing ears, and yield components. It was concluded that there is an increase in the percent of skips and multiples, and a decline in acceptable spacing as the travel speed of the planter increases. Yield was only affected when the population of plants with ears was reduced by the speed increasing
The East Pacific Rise Between 9°N and 10°N: Twenty-Five Years of Integrated, Multidisciplinary Oceanic Spreading Center Studies
The East Pacific Rise from ~ 9–10°N is an archetype for a fast-spreading mid-ocean ridge. In particular, the segment near 9°50'N has been the focus of multidisciplinary research for over two decades, making it one of the best-studied areas of the global ridge system. It is also one of only two sites along the global ridge where two historical volcanic eruptions have been observed. This volcanically active segment has thus offered unparalleled opportunities to investigate a range of complex interactions among magmatic, volcanic, hydrothermal, and biological processes associated with crustal accretion over a full magmatic cycle. At this 9°50'N site, comprehensive physical oceanographic measurements and modeling have also shed light on linkages between hydrodynamic transport of larvae and other materials and biological dynamics influenced by magmatic processes. Integrated results of high-resolution mapping, and both in situ and laboratory-based geophysical, oceanographic, geochemical, and biological observations and sampling, reveal how magmatic events perturb the hydrothermal system and the biological communities it hosts