EVALUATION OF SOME REDUCED-RISK PRODUCTS FOR MANAGEMENT OF POWDERY MILDEW IN GREENHOUSE TOMATOES

Tomato powdery mildew, caused by the fungus Leveillula taurica, is more common in greenhouses in Albania especially in second growing season where the infected plants can suffer to the point of severe economical damage if left unchecked. Growers often depend on pesticides for its control. In this study, some alternative reduced-risk products were evaluated for their efficacy to control powdery mildew in greenhouse tomatoes. Trials included Serenade WP (Bacillus subtilis QST 713: 10%), Armicarb® 100 (Potassium bicarbonate 85%), UFO (Ultra Fine Oil), Microthiol disperse WG (Sulphur 80%), compared with the untreated control. Each one of these products was applied as single treatment every 7-10 days to each of four replicates of the experimental plot at the same day. Disease severity, expressed as a percentage of the foliar infected area was assessed before each spray and five days after the last treatment. Obtained data show that Serenade, Armicarb and UFO provided more disease control evidencing a severity level by 9,2%, 12,4%, and 18,8% respectively. Microthiol disperse also shows better control compared with untreated control resulting in a disease severity respectively by 20,5 and 30,4%. Experimental results show that reduced-risk products to human health and the environment tested by this study may be considered as potential substitutes of the synthetic fungicides to control powdery mildew in greenhouse tomatoes especially in organic cropping.