Eficácia dos diferentes fungicidas e número de aplicações para o controle da ferrugem da folha no trigo

Abstract

The wheat leaf rust (Puccinia triticina) is one of the most found disease in wheat. For effective control of this disease is recommended applying mixtures of fungicides triazoles and strobilurins. The objective of this study was to evaluate the efficacy of different active ingredients and number of applications for leaf rust control in wheat. The cultivar used was TBIO Pioneiro 2010. The experimental design used was completely randomized with five treatments and four replications. The treatments were: Azoxystrobin + Tebuconazole three and four applications; trifloxystrobin + Prothioconazole three and four applications; and a control treatment without fungicide application. In the treatments with three applications, fungicides were applied at phenological stages of: elongation, booting and flowering. Treatments with four applications were made at the phenological stages of: tillering (preventive), elongation, booting and flowering. Fungicides efficiency in leaf rust control was evaluated by assessing the disease severity in the crop, calculating the Area Under Disease Progress Curve (AUDPC). The severity data were obtained through percentage notes of leaf area with visible disease symptoms compared by diagrammatic scale of Cobb. In the evaluation of PH, productivity and thousand grain weight, all fungicide treatments differed statistically from control. Fungicides based on Azoxystrobin + Tebuconazole and Trifloxystrobin + Prothioconazole were efficient in controlling wheat leaf rust.