To evaluate the efficacy of Sulfur(SC40%) against nectarine powdery mildew (Sphaerotheca pannosa(wallr.)Lev.)

Nectarine powdery mildew (Sυphaerotheca pannosa) is one of the most important fungal disease of Peach and Nectarine, it was caused necrotic spot on young fruit of Nectarine when infection occurred at first of spring, caused cracked at the surface of fruit and decreased fuit quality fruit product.The aim of this study was to evaluate the efficacy of Sulfur (SC40%) fungicide in control of Nectarine powdery mildew. The field trials were undertaken on Esfahan, Western Azarbaijan and Northern Khorasan provinces, three commercial orchards of susceptible cultivar (Shabrang) that were quiet similar and previous year were infected selected. Fungicides were applied at swelling buds, at the end of flowering and two weeks after. In this experiment, there were 6 treatments in which plots consisted of 4 trees with each treatment replicated four times and arranged in a randomized compelet block design. Fungicides were included: Dinocap (WP18.25%, 1/1000), Collis (SC30%, 0.5/1000) and Sulfur (SC40%, 3.50, 3.74 and 4/1000). Two weeks after the end spraying 10 Offshoot randomised selected from 2 trees of the central of each plot (3 from around and 2 samples above the canopy of each tree). 5 full-grown young of each Offshoot were sellected in labratoary and was assessed on base of scales considerd. The results of the analysis of variance in Esfahan and the other provinces showed that the effect of the treatments (fungicides) on the decrease of incidece and severity of powdery mildew infection is significant. Comparison of treatment of percentage and severity of infection showed. all fungicides have caused a significant decrease in the severity and incidence of infection compare with control . The results of data analysis in three regions showed that Collis (SC30%, 0.5/1000) and Sulfur (SC40%, 4/1000) fungicides had the best effects in controlling Nectarine powdery mildew and there is no significant differences among them, so Sulfur (SC40%, 4/1000) recommended for preventing progression of Nectarine powdery mildew.