Publications by authors named "Joao P A R Cunha"

The use of remotely piloted aircraft (RPA) to spray pesticides currently occurs, but knowledge about this technology is lacking due to the different locations, targets, and products applied. The objective of this study was to evaluate the control of with glyphosate applied using an RPA (10 L ha) equipped with different spray nozzles (XR 11001 and AirMix 11001). For the purpose of comparison, ground application was also performed (100 L ha).

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Weed management in areas adjacent to coffee plantations makes herbicide drift a constant concern, especially with the use of nonselective products such as dicamba. The objective of this study was to evaluate the phytotoxic effects of the herbicide dicamba alone and mixed with glyphosate as a result of simulated drift in a coffee-producing area. The study was conducted in duplicate at two different coffee cherry development stages.

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Plot size, sample sufficiency, and number of repetitions are factors that affect the experimental errors or residuals and the expression of true differences among treatments. The objective of this study was to determine, using statistical models, the appropriate sample size for application technology experiments in coffee crops through the evaluation of foliar spray deposition and soil runoff in the ground-based application of pesticides. In the first stage, we determined the quantity of leaves per set and the volume of the solution for washing the leaves and extracting the tracer.

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Distance learning presents great potential for mitigating field problems on pesticide application technology. Thus, due to the lack of teaching material about pesticide spraying technology in the Portuguese language and the increasing availability of distance learning, this study developed and evaluated a computer program for distance learning about the theory of pesticide spraying technology using the tools of information technology. The modules comprising the course, named Pulverizar, were: (1) Basic concepts, (2) Factors that affect application, (3) Equipments, (4) Spraying nozzles, (5) Sprayer calibration, (6) Aerial application, (7) Chemigation, (8) Physical-chemical properties, (9) Formulations, (10) Adjuvants, (11) Water quality, and (12) Adequate use of pesticides.

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