The seeds of the two genotypes, AKT-64 and N-8, were exposed to four doses of gamma radiation at BARC, Trombay, Mumbai, to study the impact of mutagenesis on germination and growth. About 100 seeds from each dose and a control were placed in a lab for germination. The percent germination, root length (cm), and shoot length were measured (cm). Correspondingly, treated seeds per dose were grown at the Instructional Farm of Department of Agricultural Botany, Dr. Panjabrao Deshmukh Krishi Vidyapeeth, Akola, in a randomised block design with five replications. The observations regarding plant survival, percent germination, and reduction in plant survival compared to control were observed. The seed germination and plant survival parameters for all the doses differed significantly, indicating that there was enough variation for these parameters, according to the analysis of variance in both genotypes. In laboratory condition, in both genotypes observed a progressive decrease in germination percentage, shoot length, and root length with increasing gamma ray doses. Under field conditions, in both the genotypes the maximum reduction in germination percentage was found at 700Gy (35.78% in AKT-64 and 28.44% in N-8). The LD50 was observed at 600Gy dose for AKT-64 genotype and at 500Gy dose for N-8 genotype. The highest reduction in plant survival in M1 generation was found at 700Gy dose (32.79% in AKT-64 and 26.45% in N-8) compared to both the controls. In general, a dose-dependent relationship between biological damage (%) and the type of mutagen used was observed. All biological parameters were significantly reduced by higher gamma radiation doses.

Gamma rays, Sesame, Mutagenesis, germination percentage, LD50

In the current study, it was found that increasing doses of gamma rays inhibited the seed germination and shoot and root lengths. However, the lower doses of mutagens used in this study can be effectively used to increase genetic variability. The root length showed a greater retardation than the shoot length, these showed that root system seems to be comparatively more sensitive to gamma-ray. In laboratory conditions, gamma ray doses were showed reduced seed germination percentage, seedling height (root and shoot length), and seed vigour index. On the field condition, higher doses than smaller doses had more effect on germination percentage, plant survival, and plant survival over control. The majority of the characteristics of the sesame crop plant were therefore shown to be very susceptible to gamma ray doses.

Pallavi Sasane, E.R. Vaidya, Y.C. Raut, D.T. Deshmukh, S.S. Gomashe, S.K. Burghate, R.D. Walke and Aditi Rajane (2022). Gamma Radiation's Effect on the Germination and Survival of Sesame in M1 Generation. Biological Forum – An International Journal, 14(4a): 419-422.