Increasing drought tolerance of sugarcane through gamma ray irradiation and in vitro selection

Abstract

Increasing drought tolerance of sugarcane can be done through mutation induction using gamma ray irradiation and continued by in vitro selection. This research aimed to evaluate the response of gamma-irradiated calli and drought tolerance of putative mutants through in vitro selection using selection agent polyethylene glycol (PEG). PSJT 941 variety was used as mother plant in this study. Embryogenic callus was induced on MS media supplemented with 3 mg/l 2.4-D. Six levels of gamma ray irradiation were used (0, 10, 20, 30, 40, and 50 Gy), while two levels of PEG were used for in vitro selection (0 and 10%). The observed variables were percentage of surviving calli, percentage of regenerated calli, number of shoots, shoot height, and relative decrease index. The results showed that the ability of callus to regenerate decreased with increasing doses of gamma ray irradiation. Relative decrease index of percentage of surviving calli and number of shoots emerged in irradiated calli with gamma ray doses of 10, 30, and 40 Gy in 10% PEG selection media were lower than the control (0 Gy). It was concluded that gamma ray irradiation doses of 10, 30, and 40 Gy and 10% PEG suitable to produce drought tolerance of sugarcane.