Minimização dos efeitos negativos de aplicação de agrotóxico em condições climáticas adversas

Abstract

The tecnology of aplication is the result of all processes that envolves the action of deposit pesticides in a rational, economic and safe for the environment way. This practice is directly influenced by the environmental conditions and the operations used during the achievement. During the conduct of tillage, not always ideal conditions for this are achieved, which implies the choice of new technologies or the application of knowledge already available that can minimize the negative effects of these applications. The goal of this work was evaluate th reduction of the negative effects in the applications held in adverse climatic conditions. The experiment was conducted in a commercial soybean tillage, during the harvest 2014/2015, evaluating the effects of different times of application of a pyrethroid insecticide, applied by different pressions, two different nozzles and three plant canopies with three repetitions. The deposition was evaluated using cards and processed by the software Gotas. The data were subjected to analysis of variance, and compared by Tukey’s test by 5% of probability. The results shows a bigger desuniformity in the lower parts of the lower parts of the canopy, and the greatest part of the volume applied were retained in the upper part. The pression was the factor that had the greatest influence in the canopy penetration, was observed that only the small droplets could penetrate into the basal part of the canopy. In relation of the evaluate times, the time of 2:00 P.M. presented the greatest variations for the evaluated parameters, and at the conditions of this work, provided the greatest coverage, comparing to the others. The double nozzle type presented the greatest uniformity and distribuition of the applied syrup, it was even influenced by the oil utilized and the bigger pression of work. In conclusion, the application adverse effects in inadequate condition were reduced, and the fact that the pression was the greatest factor influencing in this reduction.