Response of Sunflower New Genotypes to Charcoal Rot Disease

The charcoal rot of sunflower caised by Macrophomina pheseolina is one of the most important diseases that decreases quality and qualtity of the seed yield of sunflower. In recent years, the disease has become more widespread in Mazandaran province. Use of resistant cultivars, because of the adaptation with integrated pest management (IPM) and environment safety, has important effect on the disease management. In this study reactions of 20 lines and hybrids of sunflower to the charcoal rot disease were evaluated under field and greenhouse conditions. The results of greenhouse study showed that genotypes CMS19×R43, B line 1052/1 and CMS350.1×R43 with 24.42, 24.42 and 22.20 percent and genotype Allstar with 51.06 percent of infected plants, had the lowest and highest disease incidence, respectively. In field experiment, also genotypes CMS19×R43, B line 1052/1 and CMS350/1×R43 with 25.49, 26.39 and 33.40 percents had the lowest disease incidence and were more tolerant to the charcoal rot disease. Plant height, 1000 seed weight and head diameter of genotypes CMS19×R43 and B line 1052/1 were less effected by the disease compared to other genotypes.