1. Strawberry plants (cv. Donner) were transferred from the open into a controlled growth chamber (night temp.; 20℃, day temp.; 25℃ light period; 12 hr., dark period; 12 hr. and light intensity; 6,000 lux) on Dec. 13, Jan. 13 and Feb. 13. For each plot 0, 5, 10, 20, 30 and 50 ppm of gibberellic acid(GA) were treated, and the effect of transferring dates and GA treatments on the growth of strawberry plants was investigated.
2. The growth of petiole, leaf blade and cluster was promoted with the delay of transferring date and increase in GA concentration.
3. In the strawberry plants transferred on Dec. 13 the growth of main stem was not promoted by GA application, while in those transferred on Jan. 13 and Feb. 13 it was promoted with the delay of transferring date and increase in GA concentration.
4. No runners were produced from the strawberry plants transferred on Dec. 13, but they were produced only from GA treated ones on Jan. 13 and from all plants on Feb. 13 including the control.
5. Number of opened flowers was increased with the delay of transferring date. In the plants transferred on Dec. 13 number of opened flowers was increased with increase in GA concentration up to 20 ppm, but in others there was no close relationship between the number of opened flowers and GA concentration.
6. The effect of transferring dates and GA treatments on the number of crowns and clusters was not recognizable. The fresh weight of plants was increased wish the delay of transferring date and increase in GA concentration.
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