Seed Germination Improvement, Emergence Uniformity and Seedling Health in Flue-Cured Tobacco by Dressing and Pelleting

To improve seed germination and seedling emergence of K326 flue-cured tobacco seedlings by disinfection and pelleting, this research was conducted at Tirtash Tobacco Research and Education Center, Behshahr, Iran. Tobacco seeds were pelleted with metalaxyl, thiophanate methyl, imidacloprid, thiomethoxam and thiodicarb and disinfected by heating the seeds in hot air at 60°C for one hour, with hot water at 50°C for 10 minutes and by 0.5% sodium hypochlorite for 4 minutes. The results showed that the lowest percentage of normal seedlings, seedling emergence immediately and one year after seed pelleting and rate of germination coefficient immediately after pelleting, was in case of pelleted seeds with 2 mm diameter. Non-pelleted seeds had the highest germination and seedling emergence did not decrease significantly one year after pelleting. The results of this study showed that all seed disinfection treatments improved germination and seedling emergence percentage in floating seedbed trays and transferable seedlings, also seedlings infected with collar rot, sciaridae fly and aphids were reduced. According to the results of this study, pelleted seeds with 1.5 mm diameter had better germination and seedling emergence.