Pesticide application windows in the region of Uberlândia-MG, Brazil

Abstract

ABSTRACT:The success of the pesticide application is subject to meteorological conditions. The objective of this work was to determine the application windows suitable for carrying out the application of pesticides, using as parameters the analysis of historical data (2009)(2010)(2011)(2012)(2013)(2014) of air temperature, relative air humidity, wind speed, and rainfall of Uberlândia-MG. With an electronic spreadsheet, and using the ideal meteorological conditions for applying pesticides (an air temperature above 30°C, relative air humidity above 55%, wind speed between 3 and 12 km h -1 , and rainfall data lower than 0.2 mm h -1 ) as a parameter, the data were crossed with the aim to determine the times of day that weather conditions were ideal to obtain better efficiency in the application. According to the results, the relative air humidity was the main restricting criterion for the application windows, which are concentrated, on average, between 18:00 and 12:00 in the summer, and between 24:00 and 9:00 in the winter. The number of viable hours for a good application varied from 35 in the first fortnight of September to 198 in the second fortnight of March, demonstrating the great variability among the application windows throughout the year, which makes the generic recommendations of spraying time inadequate if the month of the year is not taken into consideration.

Eficiência de controle de cipó-de-veado por glyphosate e glyphosate + 2,4-D em diferentes horários de aplicação

“…De forma geral, as condições meteorológicas ideais para as aplicações de fitossanitários são estabelecidas como temperatura abaixo de 30°C, umidade relativa acima de 55% e velocidade do vento entre 3 e 12 km h -1 (Cunha et al, 2016). O tempo de vida de uma gota, em sua trajetória entre a ponta de pulverização e o alvo biológico, dependendo do seu tamanho, é até três vezes maior quando a aplicação é realizada a 20°C de temperatura e 80% de umidade relativa do ar, em relação a 30°C e 50%, respectivamente (Matthews, 2000).…”

Influence of Time of Glyphosate Application in the Control of Brachiaria

“…However, in several situations these requirements are not met, due to the need to spray in large areas that can occur throughout the day (morning, afternoon and evening) even in unfavourable conditions (ALVARENGA et al, 2014). These conditions are considered favourable when the temperature is below 30 °C, the relative humidity is above 55% and the wind speeds is up to 12 km h -1 (CUNHA et al, 2016).…”

<b>Mapping of the time available for application of pesticides in the state of Paraná, Brazil

“…For pesticide spraying to be successful, several factors related to the application technology must be considered, including climatic conditions (Cunha, Pereira, Barbosa, & Silva, 2016). Often, the active ingredient is lost due to environmental conditions and inappropriate application times.…”

“…Agronomy, v. 40, e39421, 2018 The availability in hours for application varies with the month, and the most appropriate months to apply pesticides are January, September, and November for the main summer crops, such as corn and soybean, and the least appropriate months are February and April, which is when the planting of the main winter crops begins (wheat and oats). The availability of hours for application also depends on the Brazilian region; in the southeast region, in the city of Uberlândia, state of Minas Gerais, a greater availability of times for pesticide application under the appropriate conditions were found for the months of November, December, January, and February, and less availability of appropriate hours for pesticide application was found in the months of August and September (Cunha et al, 2016).…”