Resistance assessment of different sunflowers varieties to Charcoal rot disease in Golestan province

Charcoal rot، caused by Macrophomina phaseolina، is one of the most important diseases of sunflower in Golestan province. Host resistance may be the only feasible method to manage this disease. Accordingly، the resistance of 18 varieties of common recommendations for the region in the form of a randomized complete block design (RCBD) against isolates of M. phaseolina was assessed. Statistical analysis of the results showed a significant difference in sunflower varieties used in this study، in case of infected plants percentage. The other recorded traits (growth period، stem diameter، head diameter، plant height، seed yield and seed weight) also showed significant differences among treatments. Based on these results، Var. R-244 and Var. Cms60/52XR-256 were introduced as the most resistant and the most susceptible varieties to charcoal rot، respectively (0. 25 and 8. 5% of infected plants، respectively)، while the highest and lowest seed yield were belonged to Var. Progress and Var. R-256، respectively.