Effect of different dosage of EMS on germination, survivability and morpho-physiological characteristics of sunflower seedling

Abstract To find out the effect of EMS dosage on sunflower variety BARI Surjamukhi-2, different EMS concentrations were compared at the molecular biology laboratory (MBL), Oilseed Research Centre (ORC), Bangladesh Agricultural Research Institute (BARI), Gazipur. A total of 10 seeds were treated with each treatment and % germination, % survival and early seedling growth was investigated. Decreased % germination was found with the increasing dose of EMS for all the treatment compared to the control, except for T 4 (0.6% EMS) treatment where a 100% seed was found to be germinated. With an exception of treatment T 4, a decreasing trend of % survivability with the increasing dose of EMS was observed. The gradual reduction with the increasing dose of EMS were observed for most of the studied characters such as leaf area, number of internodes, internode length, fresh and dry weight of leaf, dry weight of shoot, and fresh and dry weight of root in comparison to non-treated control seedlings. However, stimulatory effect with lower dosage of EMS was observed for shoot length in T 2 (0.2% EMS), root length in T 3 (0.4% EMS), and stem fresh weight in T 2 over control. Based on a quadratic regression analysis, using % survivability data, LD50 was calculated and optimum EMS dose was found 0.5%. Hence, the optimized EMS dose of 0.5% may be used to develop large scale desirable mutant of sunflower variety BARI Surjamukhi-2.