Ação e doses dos inseticidas lufenuron e lambdacialotrina no controle de spodoptera frugiperda (J. e. Smith, 1797) (Lepidoptera: noctuidae)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Assistência de ar em barra, ângulo e volume de pulverização no controle de doenças e na produtividade da cultura do trigo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Depósito da pulverização e controle de Tetranychus urticae Koch em crisântemo de corte com pulverizador assistido por ar e eletrostático

Pós-graduação em Agronomia (Proteção de Plantas) - FCA

Eficiência de volumes e pontas de pulverização centrífuga e hidráulica na distribuição e deposição da calda no controle da ferrugem asiática da soja

Pós-graduação em Agronomia (Produção Vegetal) - FCAV

Effect of working pressure at different spray nozzles on drift quantification in wind tunnel

Each year, there is an increase in pesticide consumption and in its importance of use in the large-scale agricultural production, being fundamental the knowledge of application technology to the activity success. The objective of the present study was to evaluate the influence of working pressure on the drift generated by different spray nozzles, assessed in wind tunnel. The treatments were composed of two spray nozzles AXI 110015 and AXI 11002 with pressure levels of 276 and 414 kPa. The spray solution was composed by water and NaCl at 10%. The applications were conducted at wind speed of 2.0 m s-1, being the drift collected at 5.0; 10.0 and 15.0 m away from the spray boom and at heights of 0.2; 0.4; 0.6; 0.8 e 1.0 m from the tunnel floor. To both spray nozzles, the greatest drift was collected at the smallest distance to the spray-boom and at the lowest height. The AXI 11002 nozzle gave a smaller drift relative to the AXI 110015 nozzle for the two tested pressures and for all the collection points. Regardless of the nozzle, a rise in the working pressure increases the spray drift percentage at all distances in the wind tunnel.

Influence of spray mixture volume and flight height on herbicide deposition in aerial applications on pastures

The objective of the present study was to analyze the influence of spray mixture volume and flight height on herbicide deposition in aerial applications on pastures. The experimental plots were arranged in a pasture area in the district of Porto Esperidião (Mato Grosso, Brazil). In all of the treatments, the applications contained the herbicides aminopyralid and fluroxypyr (Dominum) at the dose of 2.5 L c.p. ha-1, including the adjuvant mineral oil (Joint Oil) at the dose of 1.0 L and a tracer to determine the deposition by high-performance liquid chromatography (HPLC) (rhodamine at a concentration of 0.6%). The experiment consisted of nine treatments that comprised the combinations of three spray volumes (20, 30 and 50 L ha-1) and three flight heights (10, 30 and 40 m). The results showed that, on average, there was a tendency for larger deposits for the smallest flight heights, with a significant difference between the heights of 10 and 40 m. There was no significant difference among the deposits obtained with the different spray mixture volumes.

Translocação dos herbicidas glyphosate e imazamox em plantas de aguapé

Eichhornia crassipes is one of the main weeds found in aquatic environments, being undesirable for many activities. The aim of this study was to evaluate the translocation of glyphosate and imazamox in E. crassipes. Eight intervals were studied for cutting leaves that received herbicides: 2, 4, 6, 8, 12 and 24 hours after application (HAA), and a treatment with no cutting (untreated). The glyphosate dose was 2,160 g a.e. ha-1 (commercial product - Rodeo) + 0.5% v v-1 Aterbane adhesive spreader and imazamox at 290.4 g i.a. ha-1 (commercial product - Clearcast). The treatments were installed in a completely randomized design with four replications. Glyphosate showed a bad control for all the periods of leaf cutting. The imazamox did not provide control within 12 HAA, while from 24 HAA onward the control was effective. There was not a great mobility of the glyphosate molecule in water hyacinth plants, a period above 24 hours being needed for a satisfactory translocation. For imazamox at least 24 hours were needed after herbicide application for the translocation to occur along with subsequent control.

Tamanho de gotas de pontas de pulverização em diferentes condições operacionais por meio da técnica de difração do raio laser

The present study aimed to evaluate the droplet spectrum of hydraulic nozzles, under different pressures and spray liquid compositions, using a laser particle size analyzer. In a completely randomized design, two air induction twin flat-fan nozzles (AD-IA/D 11002 and AD-IA/D11004) and two hollow-cone nozzles (MAG - 2 and MAG - 4) were evaluated, in factorial design 3 x 2: tree spray pressures (207, 276 and 345 kPa for twin flat-fan nozzles, and 414, 483 and 552 kPa for cone nozzles); and two spray liquid compositions (water and water plus phosphatydilcoline + propionic acid adjuvant). The addition of adjuvant reduced the volume median diameter for the AD-IA/D 11002 and 11004 nozzles; however it had an opposite effect with the MAG - 4 nozzles and not changed with the MAG - 2 nozzles. In adverse weather conditions, it is not recommended the use of hollow cone spray nozzle, even with the addition of adjuvant tested because of the high risk potential of drift.

Effect of adjuvants on the amount of air included in droplets generated by spray nozzles

The air included in droplets generated by spray nozzles directly int0erferes in transport, deposition and retention of the droplets after its impact on the target. The objective of this study was to analyze the interference of adjuvants in the amount of air included in droplets generated by spray nozzles. The treatments were composed by four spray solutions containing mineral oil, vegetable oil, surfactant and water, and three spray nozzles, two air induction type and one pre-orifice. The air included was calculated by the difference between the volume of spray mix (air plus liquid) and only the liquid, which was made by means of sprayed samples captured in a funnel and collected in a graduated cylinder. The surface tension was estimated by the gravimetric method using a precision scale and a graduated pipette. The surfactant provided the largest percentage of air included in the spray. For the surface tension, the mineral oil and the surfactant had the lowest values. It was concluded that the use of adjuvants had a direct influence on the percentage of air included. In addition, products with greater ability to reduce surface tension and to form homogeneous solutions provided the increase in the percentage of air included in the droplet.

Air flow humidification for air-assisted boom sprayer

The air-assisted ground spray is fairly widespread. However, due to the unpredictable weather conditions, the operational efficiency is impaired by stops on grounds of low humidity and high temperatures. The aim of this work was to assess an air humidification method and evaluate its impact on temperature and air humidity for the air curtain of the air-assisted sprayer. With respect to relative air humidity, it has increased in 6.59%, being the maximum change when inserting 1.92 L min-1. So, it is concluded that the pipeline humidification might significantly reduce temperature and enhance air humidity. The treatments performed in this study consisted of a varied flow of a humidity device, related to weather conditions. Temperature and relative air humidity were measured at 1.0 m height from right to left of middle point of the machine, corresponding to the end of the spray boom, in the middle and end of right spray boom. The readings were also performed at three different distances from the end of the pipeline and at 0.25 and 0.50 m from that to the soil. The results show that 0.48 L min-1 in the humidification system has promoted a better efficiency in reducing air-temperature, on average 2.52 ºC when compared to the non-humidified one.

Caracterização da pulverização de mistura de tanque com diferentes pontas de jato plano

Pós-graduação em Agronomia (Energia na Agricultura) - FCA

Adjuvantes em pulverizações de fungicidas na cultura do trigo

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Qualidade da pulverização em volume reduzido para o controle do bicho-mineiro Leucoptera coffeella (Guérin-Mèneville & Perrottet, 1842) (Lepidoptera: Lyonetiidae)

Pós-graduação em Agronomia (Entomologia Agrícola) - FCAV

Influência do volume reduzido e do estádio fenológico da planta de soja no controle da Anticarsia gemmatalis (Hübner, 1818)

Pós-graduação em Agronomia (Entomologia Agrícola) - FCAV

Caracterização do aço inoxidável ASTM A743 CA6NM e do seu revestimento de WC-10Co-4Cr aspergido termicamente por HVOF

Pós-graduação em Engenharia Mecânica - FEG