Evaporation time of droplets containing  thiamethoxam and adjuvants sprayed on sugarcane leaves

João Paulo  Arantes Rodrigues da Cunha; Olinto  Lasmar; Arthur  Magri Pereira Ramos; Guilherme  Sousa Alves

Evaporation time of droplets containing thiamethoxam and adjuvants sprayed on sugarcane leaves

Autores

João Paulo Arantes Rodrigues da Cunha

Olinto Lasmar

Arthur Magri Pereira Ramos

Guilherme Sousa Alves

Editor

Universidade Federal de Goiás

Descripción

The spread and evaporation time of droplets deposited on the target affect the application efficiency of pesticides. This study aimed at evaluating the evaporation time of droplets with different sizes, under different levels of relative air humidity, containing thiamethoxam and adjuvants sprayed on sugarcane leaves. Data were collected in a climate chamber with controlled conditions, where a digital microscope was set up to record the droplet images. The evaporation time was evaluated considering three relative air humidity rates (45 %, 60 % and 75 %). For each condition, a completely randomized experiment was installed with five replications, in a 5 x 6 factorial design consisting of five sprays (water, thiamethoxam, thiamethoxam + mineral oil, thiamethoxam + vegetable oil and thiamethoxam + spreader) and six droplet diameters (337 μm, 424 μm, 486 μm, 576 μm, 831 μm and 985 μm). The evaporation time is directly and linearly related to the droplet diameter, with larger diameters requiring a longer time to evaporate. The evaporation time of droplets is also influenced by relative air humidity and spray composition. Among the adjuvants tested, the mineral oil provides the lower evaporation time for all droplet sizes.