Effect of Mutagenesis on Germination, Growth and Fertility in Sesame (Sesamum indicum L.)

In order to study the effect of mutagenesis on germination, growth and fertility in sesame, the seeds of a local variety ‘LTK-4’ were got irradiated with 6 gamma radiation doses viz., 150Gy, 300Gy, 450Gy, 600Gy, 750Gy and 900Gy at BARC, Mumbai. The seeds were also treated with 0.5%, 1.0% and 1.5% EMS. About 100 seeds of each dose along with control ‘LTK-4’ were sown in pots at CSKHPKV, Palampur during kharif, 2013. The observations were recorded on percent germination, root length (cm), shoot length (cm) and plant survival. Besides, about 2000 treated seeds per dose/concentration were grown in randomized block design with three replications each at CSKHPKV, Palampur and RSS, Akrot (H.P.) during kharif, 2013. The observations on percent germination, plant survival, reduction in plant survival over control and survival till maturity were recorded at appropriate stages of crop growth. The analysis of variance indicated that all the 9 treatments differed significantly for seed germination and plant survival parameters indicating the presence of sufficient variability for these parameters. Under field conditions, the maximum reduction in survival over control was observed in 900Gy (87.7%) while lowest was observed in 150Gy (61.9%). Likewise, percent survival was highest in 0.5% EMS (39.3%) and reduced thereafter with increasing concentration of EMS. Percent pollen fertility reduction ranged from 3.1% in 150Gy to 28.5% in 900Gy dose while in chemical mutagen, it ranged from 7.1% in 0.5% EMS to 31.5% in 1.5% EMS at both locations. Maximum injury as percent of control was observed in 900Gy dose (59.6%) and 1.5% EMS (42.2%) in chemical mutagen. Overall, a dose dependent relationship was observed between biological damage (%) and type of mutagen used. Higher doses of gamma radiations and EMS both caused considerable reduction in all biological parameters. Based upon the sensitivity of mutagens, EMS treatments were highly effective for modifying majority of the traits in the crop.