Fruit Set and Yield Enhancement in Tomato (Lycopersicon esculentum Mill.) Using Gibberellic Acid and 2,4-Dichlorophenoxy Acetic Acid Spray

Abstract

High temperature stress in summer season at plastic house is a limiting factor for tomato fruit set and yield. This study was performed to assess the effects of gibberellic acid (GA₃) and 2,4-Dichlophenoxy acetic acid (2,4-D) spray on fruit set, yield, and quality of tomato cv. ‘Adoration’(Enza Zaden Co., Ltd.) under the plastic house in Hwacheon, 2011. Four concentrations (0-, 5-, 10- and 15mg·L -1 ) of GA₃, and three concentrations (0-, 5- and 10mg·L -1 ) 2,4-D were sprayed in early flowering of tomato in the plastic house, and fruit set, yield and quality characters were observed. The results showed that spray of 10mg·L -1 GA₃ significantly increased the fruit set by 14.2% than unsprayed. The spray of GA₃ significantly increased the marketable fruit number, fruit weight, and yield. The spray of 2,4-D on blossoms significantly affected the fruit set percentage, fruit weight, marketable fruit weight and yield, and the highest fruit set observed as 62.5% in combined spray of GA₃ and 2,4-D at each 5mg·L -1 . Fruit size and total soluble solids significantly varied with the concentrations of GA₃ sprayed. The result indicates that the spray of 10mg·L -1 GA₃and 5mg·L -1 2,4-D can be more economic and effective to increase the fruit set, and yield in tomato under high temperature condition in plastic house.