Name: GILSON GERALDO SOPRANI JUNIOR
Publication date: 01/07/2024
Examining board:
Name |
Role |
|---|---|
| ADRIEL LIMA NASCIMENTO | Examinador Externo |
| EDNEY LEANDRO DA VITORIA | Presidente |
| MARCELO BARRETO DA SILVA | Examinador Interno |
Summary: Papaya production in the state of Espírito Santo has made a significant impact on the
national scene. However, this crop requires a high use of pesticides to control pests
and diseases, which are the main factors limiting production in Brazil, resulting in
significant economic losses. To overcome these challenges, it is necessary to use
chemical control programs for agricultural diseases and pests using pesticides.
Technological innovations have often not been accompanied by scientific studies on
the negative impacts of pesticides on the environment and human health. There is still
no scientific basis proving safe levels for the presence of these products in the
environment and in the human body. It is therefore essential to improve and adjust all
pesticide application processes to meet both productivity and environmental
sustainability. The main objective of this work is to evaluate a pesticide application
system for papaya in a commercial plantation. Formosa papaya cultivars were used
as targets for the application system, with a spacing of 3.0 m between rows and 2.0 m
between plants. The applications were carried out using a tractor spray set. A
randomized block design was used, organized in a 2 x 2 factorial scheme, with two
empty conical jet tips (MGA 60 and BX-AP90) and two application rates (300 and 400
L ha-1), with four replications. To analyze the droplet spectrum, water-sensitive papers
were used as targets. The papers were pinned down (Figure 4) in specific places on
the crop studied: on the upper, middle and lower thirds of the leaves, near the flowers
and near the first fruits. The quantification and characterization of the impacts on each
water-sensitive paper tag were carried out immediately after each application and
drying of the tags, using a wireless DropScope system. For the 400 L/ha application
rate, the MGA60 tip had the lowest average DMN, while the BX-AP90 had no
significant differences. At 300 L/ha, the BX-AP90 had the highest average DMN. The
right choice of tip and application rate is crucial for efficient and sustainable spraying.
Regardless of the application rate, the BX-AP90 tip had higher average coverage and
droplet density values, with a medium or large diameter, contributing to run-off. At an
application rate of 300 L/ha, the BX-AP90 tip showed a potential drift risk of 9.8%,
lower than the 15.1% of the MGA60 tip. At 400 L/ha, the BX-AP90 also had a lower
potential drift risk (13.9%) compared to the MGA60 (17.0%). It can therefore be
concluded that the appropriate choice of spray tips is essential for the successful application of liquid phytosanitary products and that increasing the spray pressure for the tips studied increased drift, recommending that lower pressures be used to reduce
losses in an application.
