R.G.Cirumalla, Manisha Sharan and Madhuri Sharon
Effect of γ- irradiation (1, 5, 10 and 15 kR) on soaked and dry seeds of Punica granatum; on the in vitro germination, seedling growth, mitotic index and amylase activity were studied. Germination initiation was 100% in all the treated and control seeds, however time taken to initiate the germination varied. Control and seeds treated with 1 and 5 kR germinated after 48 hrs, whereas those treated with 10 and 15 kR had delayed germination (i.e. after 72 hrs). Seedling growth was more inhibited when soaked seeds were irradiated than with dry seeds at all the doses of γ-irradiation. There was an arrest of mitotic index with increasing dose. With increasing dose of γ-irradiation, in both soaked and dry irradiated seeds, similar trend of decrease in amylase activity was noted i.e. in control and 1 kR treated seed amylase activity reached its peak on 7th day. With increase in irradiation dose, the time taken for maximum amylase activity decreased.
