The study was carried out in Ceballos, Mapimí, Durango. The aim was to evaluate the effectiveness of creosote bush (Larrea tridentata (DC) coville (L.)) extract to control powdery mildew in the production of melon. In a plot of 2,500 m2 an experiment was conducted using a split-split plot design; plots were the melon varieties (Crusier and Navigator), subplots were the Creosote bush extract formulations water, hydroalcoholic 50 % water and 50 % alcohol and ethanolic 96 %) and the sub-subplots corresponded to the doses (0, 1000, 5000 and 10000 mg) plant per liter of  water. Severity of powdery mildew infection due Podosphaera xanthii was evaluated at 37, 45, 53 and 61 days after sowing. The analyzed factors were independent of each other. The doses of 1,000 and 5,000 mg of creosote bush per liter of water decreased the area under disease progress curve with values of 7.9 % and 8.7 %-days, respectively. According to spatial analysis, it was found that the progress of the severity of powdery mildew infection is in the same direction of growth all the time, from the northwest, where the focus of infection is started, toward the southeast side. No effect of treatment was observed on first-fruit harvest. In the case of fruit lagged, the variety Navigator showed the best behavior for having lower production of this type of fruit waste (20.7 kg). Also, sugar content showed no effect of treatments, except for the interaction Crusier and dose of 10,000 mg plant per liter of water; where the Brix content was significantly lower (6.8).

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