Vol. 12, Issue 4 (2023)

Author(s):
Zahoor Ahmed

Abstract:
The objective of this study was to determine the change in flower morphology and the proper dose of mutagens for inducing mutagenesis in China aster (Callistephuschinensis L.). The seeds of china aster were irradiated with six doses of gamma-rays (⁶⁰Co) viz., 20 Gy, 40 Gy, 60 Gy, 80 and 100 Gy at BARC, Zakura Srinagar and treated with six doses of Ethyl methyl sulphonate viz., 0.125%, 0.25%, 0.5%, 0.75 and 1.0% in the laboratory. In order to determine the proper dose and morphological changes; germination percentage, survival rates, growth and flowering characteristics of M₁ plants were evaluated. The results revealed that germination percentage and survival rate of seedlings were decreased with increase in dose of gamma irradiation as well as ethyl methyl sulphonate during field study. It was found that low doses gamma irradiation and ethyle methyl sulphonate had stimulatory effect number of branches per plant, stem thickness and flowering parameters. A negative correlation were obtained between all plant growth and flowering with increase in gamma and EMS doses. In M₁ generation, one type of dark colour mutant at 0.75% EMS and one type of morphological mutant at 80Gy irradiation was observed. The appropriate dose for inducing mutation was found to be 93.0 Gy and 0.84% in gamma radiation and EMS, respectively.