Journal of Bio-Environment Control ISSN:1229-4675(Print) 2765-3641(Online) 생물환경조절학회지

The present study was conducted to establish an effect and a proper concentration for treatment with gibberellic acid (GA₃) and thidiazuron (TDZ), resulting with increase berry size and yield in Gaeryangmeoru grapes. Berry size was increased by treatment with GA₃, and the fruit clusters obtained for the groups treated with GA₃ concentrations of 100 and 200 mg·L⁻¹ were bigger. The berry number was also enhanced in GA₃ treated groups, but the soluble solid content and acidity was not significantly different. Damage caused by GA₃ treatment, such as peel pollination and berry shatter, was observed in the group with 200 mg·L⁻¹. The berry size was larger in group treated with a high concentration of GA₃ and TDZ respectively than in those treated with low concentrations in the treatment mixed GA₃ and TDZ; however, fruit with low soluble solid content and high acidity was harvested after GA₃ and TDZ treatment due to delay of berry ripening. The pericarp tissue layers were not changed, but the distance from the epidermis layer to vascular bundle tissue was increased as a result of GA₃ and TDZ treatment. Therefore, GA₃ and TDZ did not affect an cell division but not cell size, resulting in an enlarged berry size. It is necessary to treat plant growth regulators 2~3 times and immediately after berry set to enhance berry set rate, because the period of berry set is short. This study suggests that the proper concentration for enhancing berry size and set were up to 100 mg·L⁻¹ GA₃ or 50 mg·L⁻¹ GA₃ + 1.25 mg·L⁻¹ TDZ, and it is necessary to pay attention to harvest mature fruits because of the delay of ripening caused by the usage of TDZ.