بررسی مقایسه‌ای تاثیر محصول جدید اکسید مس + روغن ولک در کنترل بیماری پیچیدگی برگ درختان میوه هسته‌دار

Peach leaf curl disease caused by Taphrina deformans is one of the most prevalent leaf diseases on peach and nectarine trees in all over the world. This disease affects both the quantity and quality of the product and the tree lifetime, and if it is not treated, it can cause weakness and finally the death of the tree within a few years. Although the use of resistant cultivars is useful to prevent the occurrence of the disease, but since only a few number of cultivars are resistant to this disease, spraying with fungicides is the main way to control this disease. In the present study, the effectiveness of the new fungicide copper oxide + emulsifiable oil (Cuprvolck®) in controlling peach leaf curl disease in comparing to Kaptan (Kaptan® 50% WP), copper oxychloride (Mishucap® 35% WP) and copper oxide (Nordox® 75% WG) fungicides was evaluated. The experiment was carried out in the Mazandaran, Golestan and Kohgiluyeh and Boyar-Ahmad provinces in a randomized complete block design with 8 treatments and 4 replications. The treatments include copper oxide + emulsifiable oil with doses of 1, 1.5 and 2%, kaptan with a dose of 3 per thousand, copper oxychloride with a dose of 3 per thousand and copper oxide with a dose of 2.5 per thousand and controls (without any operations and with water spraying). Spraying was done in two times including the first time in autumn after the leaves falling and the second time in late winter before the buds opening. By sampling, the percentage of occurrence and the percentage of severity of the disease were calculated. The comparison of the averages of the percentage of disease occurrence and severity was done with Duncan's multiple range test. The results showed that the highest efficiency of copper oxide fungicide was related to Kohgiluyeh province and equal to 89.26%. The highest efficiency of copper oxychloride fungicide was recorded in Golestan equal to 68.85% and the highest efficiency of Captan fungicide was recorded in Mazandaran equal to 79.38%. The fungicide copper oxide + emulsifiable oil in a concentration of 2% had a good efficiency in controlling peach leaf curl disease, so that in Kohgiluyeh and Boyer-Ahmad provinces, 97.45% and in Golestan and Mazandaran provinces 73.31 and 79.38, respectively, compared to the control without any spraying, it was effective in controlling the severity of the disease. The concentrations of 1.5 and 1% of this fungicide were also effective in Kohgiluyeh. Since emulsifiable oil prevents copper oxide from being washed away by autumn and spring rains, it can help the durability of the fungicide on the plant surface. Meanwhile, another advantage of adding oil in the formulation of copper fungicides can be its effect on plant Coccoidea.