Efficacy of cyazofamid (SC 10%) Fungicide in the Control of Downy Mildew of Greenhouse Cucumber

The efficacy of Cyazofamid (Ranman SC 10%), was assessed for the control of cucumber downy mildew disease in Yazd, Tehran (Varamin) and south of Kerman (Jiroft) provinces. This fungicide was used at 1, 1.25 and 1.5 ml/L along with some comparative fungicides such as Cyazofamid (Ranman® SC 40%), fluopicolide+hydrochloride (Infinito® SC 75.68%) at 2 ml/L and Copper Oxychloride (Mishocap® WP 35%). The experiment was designed in completely randomized blocks with 4 replications in situ. To assess the efficacy of the fungicides, disease severity was calculated based on a scale described by Thomas et al.. Data were analyzed using SAS software and the means were compared using Duncan's multiple range tests. In all experiments, significance differences were observed in disease severity in plots treated with fungicide compared with control plants. In Yazd, the highest disease control rate was 87.4% in Ranman SC 10% treatment with the dose of 1.5 ml/L compared with the Ranman SC 40% (87.3%), Infinito (88.8%) and Mishocup (62.53%) were observed and in Varamin, Ranman SC 10% fungicide treatment with 1.5 ml/L resulted in control of 82.9% of disease compared with 71.8%, 71.8% and 58% control of disease by Infinito, Ranman SC 40% and Mishocap, respectively. In Jiroft area, there was no significance difference between the fungicides treatments in the disease control and the rate of disease control was 53.04% to 62.64%. The study shows that Ranman 10% SC at the dose of 1.5 ml/L has suitable efficacy for the control of the disease.