The culture of the grape, Vitis labrusca, is of great economic importance for the region of the valley of the Siriji - PE. However, in recent years, the mildew of the grapevine comes putting in rich this activity, making with that the producers sufficiently invest to resource with the fungicide use aiming at its control. Aiming at to substitute the agrotóxico use it was evaluated in the cities of Are Vicente Férrer - PE (area 1), Natuba - PB (area 2) and Macaparana - PE (area 3) the effect of the induction of resistance promoted for DL- beta - aminobutyric acid (BABA), Agro-Mos (AM) + Crop-set (Cs), Codavit (Cd) and Ecolife (Ec) was evaluated on grape variety 'Isabel'. Results have showed that AM + Cs was superior to the others treatments in reducing disease severity. In relation to efficiency control the AM + Cs treatment reduced disease severity in 37,46%, 35,97% and 18, 57% in the area 1, 2 and 3, respectively. The disease severity in the areas 1, 2, and 3, fitted the Y= e-3,36 . e-0,019t- (R= 0,66**), Y= 1/1 + 14,63 .e-0,037t (R= 0,84**) and Y= e-4,13 . e- -0,034t (R= 0,62**), respectively. The severity of downy mildew in function of the time in the area 1, fit the gompertz model, except in the BABA treatment that was described by the equation logstic. In the area 2, a predominant model did not fit data from all treatments. The monomolecular model was described more frequently than others, in the treatments of area 3.
Plasmopara viticola; grapevine; disease control
