Spray nozzles and curtain of chains in fungicide application to control Asian soybean rust

Abstract

The proper choice of spray nozzles and spray boom configuration is of paramount importance for fungicidal effectiveness, promoting better foliar coverage, especially in the lower canopy of the crop. In this sense, the present study evaluates the influence of fungicides applied with different spray nozzles, with and without curtain of chains, on Asian rust control and on the yield of soybean cultivar BMX Ativa RR. The experimental design was a randomized block, with four spray nozzles (Albuz^® ATR 1.0; Albuz^® ATR 0.5; Magnojet^® ADT 11002; and Magnojet^® CH100) and two spray boom configurations (with curtain of chains; and without curtain of chains). The experiment had four replicates and a control without fungicide application. The variables under study were the severity and control of Asian soybean rust, thousand grain weight, and soybean yield. The results indicate that using the curtain of chains in fungicide applications is a technically viable alternative to increase soybean yield. When used along with empty conical jet and triple flat jet nozzles, this technology is highly efficient in controlling Asian soybean rust.