Mutagenic effect of gamma rays and EMS on agronomical traits of niger (Guizotia abyssinica Cass.)

Abstract

This study was conducted to augment genetic variability in niger plant (Guizotia abyssinica Cass.) using gamma rays and ethyl methane sulphonate (EMS) Niger (G. abyssinica) seeds of cultivar N-71 were exposed to various doses of gamma rays which ranged from 24 to 28 KR and different concentrations of EMS which ranged from 0.2 to 0.4% and in combination. Morphogenic and agronomic traits in the M1 and M2 generations that analyzed included: percentage of germination and survival, plant height, number of branches, capitulum size, number of ray florets per capitulum, number of disc florets per capitulum, head size, number of capitula per plant, number of seeds per capitulum, seed yield per plant and 1000-seed weight. The results of the present study showed that the three gamma irradiation doses used (24, 26 and 28 KR) had decreasing effect in most of the agronomic and morphological traits evaluated in M1. However, combination treatments like 24 KR+0.2% EMS and 26KR+0.4% EMS showed a noteworthy increase of grain yield and yield related components. In general, for the three irradiation doses in M1 population, there were no significant changes observed in morphological traits, however, in progenies of collective mutagenic treated seeds some potential high-yielding mutants were identified.