Evaluación de dos hidrosoles vegetales para el manejo de la cenicilla (Leveillula taurica) en el cultivo de cebolla blanca (Allium fistulosum)

Abstract

Welsh onion (Allium fistulosum) can be attacked by several diseases caused by phytopathogens, including powdery mildew caused by Leveillula taurica, which can cause economic losses if effective control measures are not implemented. Due to the problems associated with the indiscriminate use of chemical products, the use of alternative agro-sustainable products has increased. In this research, the effect of two plant hydrolates for the management of powdery mildew in Welsh onion crops in the Saquisilí municipality was evaluated. The effect of rosemary hydrolate and molle hydrolate at concentrations of 1.0, 1.5 and 2.0 cc/L was evaluated on the incidence and severity of powdery mildew. The results were compared with the effectiveness of a commercial product (emulsifiable neem oil). The results demonstrated the efficiency of both hydrosols, however, the greatest reduction in incidence was observed with the application of rosemary hydrosol at doses of 1.5 and 2.0 cc/L. Similarly, the severity of powdery mildew in white onion plants was lower in plants treated with both types of hydrosols, with the effect being greater after the second application when the severity reached between 1.1 and 4.7% with rosemary hydrosol and between 0.9 and 3.3% with molle hydrosol. The lower incidence and severity of powdery mildew translated into better and greater plant growth and consequently into better crop yield. In view of the low costs of obtaining it and its effectiveness, the use of rosemary hydrosol at a dose of 1.5 cc/L is recommended as an alternative for sustainable management of powdery mildew in white onion since it has proven to be effective in significantly reducing the incidence and severity of the disease.