Among the three rusts diseases in the of corn crop, the tropical rust caused by Physopella zeae (Mains) Cummins & Ramachar is highlighting by its aggressiveness. The objective of this study was to evaluate the fungicides mixtures action azoxystrobin + cyproconazole and epoxiconazole + pyraclosytrobin in the control of the tropical rust of corn in the culture of the crop. The experiment was carried out in the experimental area of the Department of crop protection of UNESP, Jaboticabal, São Paulo State, Brazil, during in the period of January to May of 2006. Were evaluated in the field plots were arranged in the complete randomized blocks, with 6 treatments and 4 replications. The used treatments were (mL of c.p./ha): 1- control; 2-epoxiconazole + pyraclostrobin 500,; 3-epoxiconazole + pyraclostrobin 750,; 4-azoxystrobin + cyproconazole 300 + mineral oil 0,50%,; 5-azoxystrobin + cyproconazole 300 + mineral oil 0,50% and 6 - azoxystrobin + cyproconazole 450 + mineral oil 0,50%. All the treatments fungicide spray were applied to maize at the stage V8, and the treatment 5 was replicated in the beginning of the tasseling. It was realized seven evaluations of the disease severity were performed every seven days. The curves of progress of the disease were analyzed by using three transformations models (monomolecular, logistico and of Gompertz). The AUDPC (Area Under the Disease Progress Curve) was calculated from which the analysis of variance was performed and the averages were compared by the Tukey test at the level of 5% of probability. The analysis no found difference significant statistics among the treatments 6, 5 and 4, which these showed smaller AUDPC. We concluded that the monomolecular model it was best model adjusted to the data.
Chemical control; Physopella zeae; AUDPC
