Gamma radiation is the most commonly used mutagen in plants as it causes a high frequency of induced mutations. It can be used to overcome the difficulties in papaya breeding to get true to type plantlets especially in dioecious varieties. An optimum dose is highly desired to produce the high frequency of mutations with minimum killing of treated individuals. Therefore, the present investigation was undertaken to determine the LD50 of gamma rays and effect of different dosages of gamma rays on morphological, physiochemical, biochemical parameters of papaya. In the preliminary dosimetry study, seeds from two papaya varieties, Ranchi Local and Arka Surya were irradiated in a gamma chamber at Bhabha Atomic Research Centre (BARC), Mumbai with 7 different radiation doses ranging from 10 Gy to 70 Gy at every interval of 10 Gy. | Standardisation of gamma dose in papaya cv. ranchi local and arka surya
