Produtividade de milho segunda safra após a aplicação de fungicida por via aérea e terrestre

Abstract

The fungicide application (aerial and terrestrial) was carried out to control fungal diseases in the second season maize crop in 2013 and 2014 agricultural years in order to evaluate the its application quality. The study was conducted at São Bento Farm, municipality of Goioerê, Northwestern Paraná, according to the following geographical coordinates: latitude 24°13'04.14" South and longitude 52°56'08.36" West and altitude of 521 meters. The hybrid PIONEER 30K75 BT HERCULEX was used to evaluate the diseases severity before and after fungicide application (strobilurin + triazole), liquid mixture deposition and productivity. The aerial application was carried out with an Ipanema aircraft model in spray volumes of 7.5; 13.5; 20 and 30.3 L h‾1 with rotary atomizing nozzles. In the terrestrial application, it used the self-propelled spray of Stara brand, Gladiator model, with the following volumes: 90; 110; 130 and 150 L ha‾1, and even flat spray ends with air induction. One treatment without fungicide application was used as a control. The experimental design was carried out in groups and the study of liquid mixture deposition was carried out with the use of hydro sensitive papers that were set in the third upper, middle and lower part of maize plants. The aerial and terrestrial treatments showed a satisfactory control on maize disease for two consecutive years of research. The greatest drops coverings were obtained in 30.3 L ha-1 for aerial application and 150 L ha-1 volumes on terrestrial application. Average maize yields on terrestrial application were 3,400 and 3,976 kg ha-1, respectively, in 2013 and 2014. However, for aerial application, 3,392 and 4,293 kg ha-1 were recorded in 2013 and 2014, respectively. Maize yield of controls were 3,100 and 2,800 kg ha-1 for 2013 and 2014, respectively, in the terrestrial application. In aerial application, the control yield was 2,200 kg ha-1 in 2013 and 3,100 kg ha-1 in 2014. There was no significant difference in maize productivity according to the different volumes tested for both techniques of application, when compared among themselves, however, all treatments were superior to the control.