Mutation induction using gamma irradiation on oil palm (Elaeis guineensis Jacq.) cultures.

This article reports on in vitro mutation induction in oil palm (Elaeis guineensis Jacq.) using gamma irradiation. The radiosensitivity tests were carried out to determine the level of gamma dose suitable for oil palm cultures with good regenerative capacity. Calli from Clone C3-5, Clone GP13-0, Clone GP13-1 and Clone C7-1 were exposed to various levels of gamma radiation (GR) from 0 to the highest 100 Gray (Gy). Of these, embryogenesis was observed in Clone C3-5 and Clone GP13-0 at 40 Gy and at lower doses of GR. The mean weight of callus growth was halved at about 40 Gy to 60 Gy of gamma rays. AFLP analysis was carried out on these callus cultures to monitor changes in the DNA profile. The DNA changes were observed even at a dosage as low as 10 Gy. The changes observed were basically random in nature. For a mutation induction study, leaf derived calli from a selected ortet was used. Friable callus from Clone CX49, Line A' and Line B' were exposed to both fractionated and acute irradiation. When fractionated irradiation was used, there were no significant differences in the establishment of polyembryoid cultures and shoot production. In this study, the highest gamma ray dose was 5 Gy repeatedly given for three and five times at 4-5 subculture intervals. Under acute irradiation with doses of 0, 20, 40, 60, 80 and 100 Gy, the embryoid growth decreased significantly at doses of 40 Gy and above, which also affected the shoot regeneration.