عنوان مقاله [English]
To study the effect of gibberellic acid and cold shock on dormancy breaking of potato minitubers Var. Agria, a factorial experiment based on completely randomized design with four replications was used. Studied factors included: 1. Gibberellic acid (1000 ppm and Control) and 2. Cold shock at 2°C (C1: no cold, C2: a week of cold, C3: two weeks of cold, C4: three consecutive weeks of cold, C5: three intermitant weeks of cold). Germination percentage, number of sprouts/minituber, length of sprouts,field establishment of minitubers and yield/unit area were studied. Results showed that GA significantly stimulated minitubers germination. In the case of 1000 ppm GA, the number of sprouts/minituber was the highest in all levels of cold shock, while in the absence of GA, cold shock significantly increased number of sprouts/minituber and this trait significantly reduced by prolonged cold period. GA significantly increased field establishment of minitubers. In the case of GA, number of produced tubers/unit area was not significantly different in cold shock levels while in the absence of GA, this trait significantly increased by prolonged cold shock.