Abstract

The current research was carried out with the objective of evaluating the radiosensitivity of shoot tips from henequen (Agave fourcroydes) to Gamma radiations 60Co and to determine the optimum dose of radiation for improvement program in the cultivar Sac Ki. Shoot tips of 20 days of culture in vitro were selected and irradiated with five doses between 10, 20, 30, 40 and 50 Gy using a 60Co source. Evaluations were aimed to determine the increasing of fresh weight of explants in relation to the control (no irradiated material) and number of dead explants average number of axillary shoots per explants. Percentage of mortality rose when irradiation dose was increased. Irradiation 20 Gy was GR50, increasing fresh weight of explants in a 49.6% in relation to control. LD50 was 30 Gy and a 50% of irradiated explants died. Increasing irradiation dose the number of explants decreased, though starting of sprouting took place after 90 for both, irradiated and non irradiated explants, suggesting that this parameter was not radiostimulated nor radioinhibited. Results enable to suggest the application of 20 Gy in studies aimed to create genetic variability in breeding programs by mutation induction.