Gibberellin Application Method and Concentration Affect to Growth, Runner, and Daughter Plant Production in ‘Maehyang’ Strawberry during Nursery Period

Abstract

This study was aimed to evaluate the effect of application method and concentration of gibberellin A3 (GA3) on the growth, runner production, and seedling quality of strawberry plants (Fragaria × ananassa Duch. cv. Maehyang) during nursery period. The mother plants of strawberry were transplanted in pot (64 × 27 × 18 cm) filled with commercial growing medium on March 20, 2018. GA3 concentration was applied as 0, 50, 100 or 200 mg·L -1 with spray or drench to 45 mL per plant at 4 weeks after transplanting, respectively. Nutrient solution was supplied with the EC 1.5 dS·m after the transplanting and supplied 350 mL per pot twice a day (15 min per one time) after rooting. The growth characteristics of mother plants of strawberry were measured at 7 weeks after treatment, and growth characteristics of daughter plants of strawberry were measured at 10 weeks after treatment. Runner length and diameter of mother plant was the longest or thickest in the spray with 200 mg·L than the other treatments, respectively. Soil-plant analysis development (SPAD) value of mother plant was the lowest in spray with 200 mg·L. However, leaf length, leaf width, and crown diameter showed no significant differences in all treatment among application method and concentration of GA3. As the concentration of GA3 increased, physiological disorder like stretchiness of crown occurred more. The physiological disorder was the most occurred in spray treatment with 200 mg·L, but drench treatment occurred less than spray treatment. The number of runners and daughter plants increased with increasing concentration of GA3 regardless of application methods. In the growth characteristics of the daughter plants, leaf length and leaf width of first daughter plant, plant height, crown diameter, leaf area and SPAD value of second daughter plant, and plant height of third daughter plant were the significantly greatest in drench with 100 mg·L treatment. This results indicate that growth and runner production of mother plants and growth of daughter plants of strawberry were the best achieved by drench application in the 100 mg·L GA3. Additional key words : drench, Fragaria × ananassa, GA3, number of runners, spray