Controle químico com monitoramento de doenças do trigo na região de Dourados-MS

Abstract

The objective of this work was to evaluate the effect of two fungicides to control the main diseases on wheat in the region of Dourados – MS, under different fungicide’s sprayings based on phenological stages (booting and maturation) and on the disease occurrence. The experiment was carried out in crop conditions at Experimental Farm and Microbiology and Plant Pathology Laboratory of Federal University of Grande Dourados. The experimental design was in randomized blocks, represented by four replicates and five control programs. The adopted programs were: T1 (control: no spraying), T2 (two spraying of Azoxistrobin+Mancozeb on booting and maturation), T3 (one spraying of Azoxistrobin+Mancozeb based on incidence diseases), T4 (two spraying of Azoxistrobin+Ciproconazol on booting and maturation), T5 (one spraying of Azoxistrobin+Ciproconazol based on incidence diseases). The evaluated diseases were: wheat leaf rust (Puccinia triticina), wheat leaf blight (Bipolaris sorokiniana), tan spot of wheat (Dreschslera tritici-repentis), wheat blast (Magnaporthe grisea), head blight of wheat (Gibberella zeae) and pathogens related to seeds. The evaluated characters were: disease severity, wheight of hectolitre (WH), yield and sanity of harvested grains. The variables yield and WH have not shown significant alterations in the different chemical control programs. The fungicide Azoxistrobina+Mancozeb have shown better effect when preventively sprayed in P. triticina. The fungicide Azoxistrobina+Ciproconazol have demonstrated itself more viable in sprayings in accordance with the disease monitoring.