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Made available in DSpace on 2018-12-11T16:45:05Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-01-01. Added 1 bitstream(s) on 2019-10-09T18:29:03Z : No. of bitstreams: 1 S0100-69162016000601118.pdf: 357183 bytes, checksum: c57d37f1771ce0fc47fb485ee70a0603 (MD5) The effect of blade angle on droplet size spectrum of five rotary cage atomizers and one rotary disc atomizer used in Brazil was evaluated in a high speed wind tunnel, with an air speed of 180 km h-1. This study included the characterization of the droplet size spectrum, via laser diffraction instrument, generated by three blades angles, of 45, 60 and 75 degrees. The spray solution was composed of Picoxystrobin + Cyproconazole fungicide (SC), at 20 mL c.p. L-1, and at a flow rate of 6 L min-1. As the angle decreased from 75 to 45 degrees, the rotational speed of the atomizers increased and the volume median diameter (VMD) decreased. However, increasing the rotational speed also increased the percentage of droplets smaller than 100 μm (% < 100 μm). At the blade angles of 45 and 60 degrees the atomizers showed that %

Made available in DSpace on 2018-12-11T17:33:14Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-11-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) The influence of three types of commercial formulation of insecticides and fungicides, emulsifiable concentrate (EC) formulation, suspension concentrate (SC) formulation and water dispersible granule (WG) formulation on the surface tension, viscosity and the droplet size spectra of sprays was evaluated using thirty commercial insecticide and fungicide products. The concentration of sprays was based on application water spray volume of 50 L ha−1 using an XR 8003VS flat fan nozzle, operated at 200 kPa pressure. The lowest surface tensions were obtained with EC formulations, while the SCs had the highest viscosities. Emulsions were the most effective at decreasing the percentage of droplets smaller than 100 μm and relative span, while increasing the DV0.1 and DV0.5 values than the dispersion-type formulations, represented by WG and SC formulations. These factors should be considered for planning spray applications and reducing drift. Sao Paulo State University UNESP, 1780, Dr. Jose Barbosa de Barros Street University of Nebraska-Lincoln, 402, West State Farm Road Sao Paulo State University UNESP, Prof. Dr. Antônio Celso Wagner Zanin Street Sao Paulo State University UNESP, 1780, Dr. Jose Barbosa de Barros Street Sao Paulo State University UNESP, Prof. Dr. Antônio Celso Wagner Zanin Street CNPq: 99999.003632/2015-06

This paper aimed at investigating the knowledge level of people working on pesticide spraying activities concerning spray adjuvant properties, as well as collecting information on disposal locations for residues from internal spray tank cleaning, and finally the understanding of pesticide spray drift occurrence in the state of Mato Grosso, Brazil. The information was gathered through a questionnaire answered by participants of a rural extension program in application technology located in nineteen grain and fiber producing regions of Mato Grosso state. Among the mentioned adjuvants, 49.0% belonged to the mineral oil class and 17.9% of participants did not know the functions performed by such products. In addition, 58.5% of the participants discarded residues into the field. Among the participants who answered the question about spray drift occurrence causes, 54.1% indicated problems relating to inadequate weather conditions. In conclusion, there is a lack of knowledge on adjuvant functions, besides of inappropriate residue disposal in the state of Mato Grosso. Spray drift was referred as a problem; however, most of participants were not able to discuss the causes of these losses. RESUMO O objetivo deste trabalho foi investigar o nível de conhecimento de trabalhadores ligados à atividade de aplicação de defensivos agrícolas sobre as funções de adjuvantes de calda e coletar informações sobre os locais de descarte dos resíduos provenientes da lavagem interna do reservatório de calda de pulverizadores, ocorrência e motivos da deriva, nas aplicações de defensivos agrícolas, no Estado do Mato Grosso. As informações foram coletadas por meio das respostas de um questionário entregue aos participantes de um programa de extensão rural, em tecnologia de aplicação, em dezenove municípios produtores de grãos e fibras do Estado. Ao todo, 49,0% dos adjuvantes citados pertenciam à classe dos óleos minerais e 17,9% dos participantes declararam não saber as funções desempenhadas pelos adjuvantes. Os resíduos eram descartados nas lavouras por 58,5% dos participantes. Dentre os participantes que responderam sobre as causas da ocorrência de deriva nas aplicações, 54,1% indicaram problemas relativos às condições climáticas inadequadas. Conclui-se que há carência de conhecimento sobre as funções desempenhas pelos adjuvantes, bem como a ocorrência de descarte de resíduos em locais inadequados no Estado do Mato Grosso. A deriva foi reconhecida como um problema, mas a maioria dos participantes não se propôs a discutir as causas deste tipo de perda.