efficacy of beltanol (sl 37.5%) on damping-off disease of cucumber

Damping-off disease caused by phytophthora melonis is the most common disease of cucumber seedlings cucumis sativus l.. to study the efficacy of 8-hydroxy quinoline sulfate (beltanol®) in control of cucumber damping-off disease, glasshouse experiments were carried out with six treatments at research stations in tehran, alborz, and semnan provinces in iran. treatments included 0.3, 0.4, and 0.5 ml∙l-1 of beltanol as the experimental fungicide, metalaxyl+mancozeb (rosalaxyl® wp 72%; frac code 3 + m03) at 2 g∙l-1 as the standard fungicide along with inoculated and untreated and non-inoculated (healthy) controls. cucumbers were cultivated from seed in trays, and treatments were applied twice. once after seed sowing and second time at the 2-leaf stage. disease incidence was recorded at the 4-leaf stage. beltanol at 0.3 ml∙l-1 had the least effect among fungicides, with nearly 50% of treated plants showing signs of disease. application of beltanol at 0.4 and 0.5 ml∙l-1 decreased disease incidence by 59.55 and 64.47% compared to the inoculated control, respectively. rosalaxyl® performed better than beltanol and reduced disease by 83.55%. however, to provide alternatives for proper fungicide rotations, beltanol at the rate of 0.4 ml∙l-1 may manage damping-off disease in cucumber.