Abstract

The effects of gibberellic acid treatment and light conditions on the germination of true potato seed were investigated. The treatments included pre-soaking with different concentrations of GA₃ for 24 h and the addition of different concentrations of GA₃ to the MS medium. Different light conditions were also examined. One set of each treatment was placed in 16 hours of light and 8 hours of dark. The other set was placed in 24 h of dark for a week and then placed in the same condition as that of the first set. The percentage of seed germination scored two weeks after sowing was analyzed using the three-way analysis of variance. No interaction between two or three factors was observed, but all three factors were individually significant at a 99% confidence level. Consequently, individual analysis of the three factors revealed that 1) the effect of pre-soaking with 4,500 ppm of GA₃ was the best, but not significantly different from that of 500 and 1,500 ppm; 2) the effect of 0.5 ppm of GA₃ in the medium was the best, but not significantly different from that of 1 ppm; and 3) the effect of dark condition for one week after sowing was highly significant.

Key words: Germination, gibberellic acid, light condition, potato (Solanum tuberosum L.), seed dormancy, true potato seed.