<b>Effect of different volumes and adjuvants in the air and ground spraying in the maize culture</b>

Abstract

The experiment was conducted in the 2007/2008 crop in the city of Carambeí (PR) Brazil, Latitude 24° 55’ 04’’ S, Longitude 50° 05’ 50’’ W. The objective was to evaluate the effect of different spray volumes and spray adjuvants in air and ground application of fungicide in corn. The treatments consisted of application of the chemical fungicide strobilurine (pyraclostrobin) and triazolam (Epoxiconazol) with concentration 133/50 SC at a dose of 0.7 L ha^-1 (93.1 / 35 i. a), applied at rates of 10 and 20 L ha^-1 in aerial spraying and 150 L ha^-1 ground spraying, and adjuvants used were: a) vegetable oil rectified, b) mineral oil patch c) synthetic adjuvant. The main results found were that in the aerial spraying the dose of 20 L ha^-1 causes drop spectrum with most appropriated characteristics as the volume median diameter, penetration of drops and potential risk of drift, for the application of 10 L ha^-1. It can be used an intermediate flow rate (15 L ha^-1) as an alternative for application of fungicides on maize. In the spectrum of spray, droplets of larger diameter tend to reach the leaves of the middle and upper third of leaves and lower third receives drops of smaller diameter and lower density per unit area compared to the leaves of thirds higher in the plant.