کارآیی مخلوط بردو (SC 20%) در کنترل بیماری پیچیدگی برگ هلو با عامل Taphrina deformans (Berk.) Tul.

Peach leaf curl caused by Taphrina deformans (Berk.) Tul. is one the important disease of peach that damage the quantity and quality of crops in many peach-rich areas of Iran. In infected trees, fruit set is reduced or stopped and if the trees are not properly treated, it can cause the death of tree within a few years. With proper use of appropriate and effective fungicides can significantly reduced economic losses due to the disease. Copper compounds are one of the oldest fungicides that are used for chemical control of peach leaf curl disease. Bordeaux mixture (Burgundy® SC 20%) fungicide, the product of Samiran Company is a copper fungicide. In the present study, its efficacy compared with other fungicides, Captan (Kaptan® 50% WP), Copper oxychloride (Mishocap® WP 35%) and copper oxide (Nordox® 75% WG), to control peach leaf curl disease. The experiment was carried out in North Khorasan, West Azerbaijgan and Mazandaran provinces in a Randomized Complete Block Design (RCBD) with 8 treatments and 4 replications. Treatments included 2.5 ml/l of Nordox, 3, 5 and 8 ml/l of Bordeaux mixture (Burgundy® SC 20%), 3 g/l of Mishocap® and 3 g/l of Captan and controls (without any spraying and with water spraying). Treatments were applied at two stages (first one, at the end of autumn after the leaves fall and the second, early spring before bud swelling). Two weeks after the first symptoms observed on control plots, leaves were randomly sampled for disease incidence and severity assessment. Disease incidence percentage and disease severity percentage were measured and analyzed using SAS software in the three provinces. Mean comparison of disease severity and disease incidence percentages were done by Duncan's multiple range test (P =5%). Result showed that, there are significant differences between treatments and controls in all three provinces (P = 5%). In North Khorasan, treatment related to 3, 5 and 8 ml/l of Burgundy and Captan fungicides had the best efficacy for disease control. In West Azerbaijgan, all fungicides were efficient for controlling the disease. In Mazandaran province, Captan and Nordox had the best efficacy. In general, according to the results of three provinces, fungicides Burgundy in 5 to 8 ml/l, Captan in 3 g/l and Nordox in 2.5 ml/l had high relative advantage in peach leaf curl disease control.