Determination the effective dose of mutation in pepper (Capsicum annum L.)

This study was carried out to determine the "Effective Dose of Mutation” (EMD50) for mutation breeding study on Çermik, Kandil and Üçburun pepper varieties grown intensively in Diyarbakır. For this purpose, pepper seeds were exposed to chemical mutagen source Ethyl Methane Sulfonate (EMS) at doses of 0%, 01%, 0.2%, 0.3%, 0.4%, 0.5%, 0.75% and 1% and to irradiation with physical mutagen source Co60 at doses of 0, 50, 100, 200, 300, 400, 500 and 600 Gy. In irradiated and chemically exposed seeds, on the 45th day following seed sowing date, germination percentage (%) for each dose was calculated and seedlings’ lengths were measured to investigate the effects of different doses and EMD50 value was calculated. According to the data obtained as a result of the study; it was found that the germination rate in pepper seeds of all three varieties-genotypes gradually decreased with the increases of doses in application of EMS on pepper seeds. While the decreases were especially evident in the seeds of Kandil and Üçburun varieties subjected to 0.3% EMS dose and 9 hours of application; in Çermik genotype the germination rate started to decrease with 0.5% EMS dose due to local population. It was also found that germinations decreased in all three varieties depending the application of 300 Gy CO60. In 6-hour EMS application, EMD50 values were respectively determined as 0.67%, 0.97% and 1.08%. for Kandil, Üçburun and Çermik. And for 9-hour EMS application, EMD50 values were determined as; 0.52%, 0.77%, 0.89%. Kandil, Üçburun and Çermik varieties. According to the results obtained in the study, the usage of both physical and chemical mutagens in pepper varieties; increasing of doses and durations of mutagens, decreased germination rates and also caused to decrease the plant heights. As a result, it seems possible to obtain variations in peppers with the usage of physical and chemical mutagens to get new varieties in plant breeding.