The effect of light and gibberellic acid concentrations on breaking dormancy of potato micro tuber

Abstract Potato (Solanum tuberosum L) is one of Indonesia’s priority crops considering its nutritive benefit as a carbohydrates source in food diversification. Potato tubers are classified as stem tubers, so the tubers such as micro tuber can appear in the stem of in vitro cuttings. The research aimed to determine the effect of GA3 concentrations (0, 5, 10, 15, 20 ppm) and storage conditions, e.g., Dark (T1) and light (T2), on breaking dormancy of potato micro tubers. This experiment was conducted in the Tissue culture Laboratory of IVEGRI from April until September 2018. The experiment used a randomized block design with 3 replications; each treatment consisted of 40 micro tubers of Granola (var.) with size ranged >3 - <4 g per each. The result showed that storage conditions gave significant differences to the percentage of breaking dormancy for 4-6 weeks, and GA3 concentration did not affect the average number of shoot, average shoot length in concentration 5 until 20 ppm. The average shoot number, shoot lengths were 0.63 – 2.20 per tubers, 7.50 – 20.13 mm, respectively. There was no interaction between treatment. Visual observation concluded that storage in light conditions produced shoots with better quality than ones in dark conditions.