Effects of Preharvest Gibberellic Acid Applications on Fruit Quality of ‘0900 Ziraat’ Sweet Cherry

Abstract

The objective of this study was to determine the effects of gibberellic acid (GA3) applications on fruit quality of ‘0900 Ziraat’ sweet cherry (Prunus avium), a low cropping and a large-fruited variety. ‘0900 Ziraat’ trees were sprayed with 0, 15, 20, and 25 ppm GA3, when the fruit were at their straw-yellow color stage. Fruit quality was evaluated at harvest in terms of size, firmness, pedicel length, and soluble solids content (SSC) to determine the optimum application. Fruit treated with GA3 were significantly larger and firmer than the controls. There were no differences in fruit firmness within the different levels of GA3 treatment; however, fruit treated with 20 and 25 ppm GA3 were significantly larger than the fruit treated with 15 ppm GA3. Trees treated with the optimum concentration of GA3 (25 ppm) in two different locations yielded fruit with 13.4% and 14.1% greater weight and 38% and 25% higher firmness. GA3 treatments did not affect pedicel length. The effect of GA3 application on SSC was complex; there was a significant interaction between GA3 and location. Being firmer than the controls, the GA3-treated fruit could be harvested at a later date than the controls.