Foliar Spray with Different Agrochemicals on Fruit Quality and Exportability of ‘Washington’ Navel Orange Fruit ( <i>Citrus sinensis</i> L.)

Abstract

The present study was carried out to improve fruit set, yield, quality, marketability, and exportability of ‘Washington’ Navel orange. Pre-harvest foliar sprays of GA3, K, and Ca, either alone or combined, were applied at full bloom. The following treatments were applied: {control (T1), 25 mg/L GA3 (T2), 2% K2SO4 (T3), 25 mg/L GA3 + 2% K2SO4 (T4), 25 mg/L GA3 + 2% Ca Cl2 (T5), 2% K2SO4 + 2% Ca Cl2 (T6), and 25 mg/L GA3 + 2% K2SO4 + 2% Ca Cl2 (T7). All treatments improved fruit set, yield, physical and chemical characteristics, mineral content of leaves and fruit rind, and the percentage of exportable fruit in comparison to the control. Fruit set, fruit detachment force, peel firmness, and the mineral content of leaves and fruit rind were enhanced significantly with the combination of GA3 + K2SO4 + Ca Cl2 (T7) in comparison to all other treatments and the control. Results indicated that all foliar combination treatments improved fruit quality and marketability, and increased the percentage of exportable fruit and reduced the defects of non-exportable fruit.