Preharvest calcium applications improve postharvest quality of papaya fruits (Carica papayaL. cv. Eksotika II)

This research was conducted to evaluate the effects of calcium chloride (CaCl2) and calcium nitrate Ca(NO3)2 on nutrient concentrations and post-harvest quality of papaya fruits. In the first experiment, plant stem height increased significantly after Ca(NO3)2 application compared to CaCl2. Calcium content in peel and pulp for both sources significantly rose with increasing calcium concentrations, but there was a significantly higher content of calcium in fruit peel and pulp in the CaCl2 treatment. Magnesium and potassium in fruits decreased with increasing calcium concentrations. A reduction in anthracnose lesion diameter in infected fruit with increasing calcium was observed for both CaCl2 and Ca(NO3)2 treatments. Ethylene production in fruits decreased with increasing calcium concentrations. In the second experiment, only CaCl2 was used as calcium source and results showed that calcium content in fruit peel and pulp significantly increased at higher CaCl2 levels, whereas ethylene production, anthracnose lesion diameter and magnesium contents decreased compared with control.