Effect of pre-harvest potassium foliar spray and postharvest storage methods on quality and shelf life of cherry tomatoes

Abstract

Potassium (K) foliar sprays as a pre-harvest treatment and storage methods as a postharvest treatment were applied to get the effects on quality and shelf life of cherry tomatoes. The supplied nutrient solutions were regulated to EC 2.5 dS m(-1) and pH 5.8-6.2. The control (distilled water), 10.23 mM potash of potassium chloride (KCl), 10.23 mM potash of potassium nitrate (KNO3) and 36.74 mM potash of monopotassium phosphate (KH2PO4) were sprayed for 5 weeks. Harvested tomato fruits were stored at 5 degrees C in boxes (commercial size) and in oxygen transmission rate film as a modified atmosphere packaging. Ca, K, P and Cu contents in KH2PO4-treated tomatoes were higher compared with other treatments. KH2PO4 -treated tomatoes had the lowest fresh weight loss, respiration rates, ethylene emission which prolonged the shelf life. The shelf life KH2PO4 -treated tomatoes were 25 days for MAP storage and 20 days for box storage. Moreover, the firmness, soluble solids and glucose content were increased by the KH2PO4 treatment and they were retained after storage. KH2PO4 -treated tomatoes influenced the color, lycopene and titratable acidity during the storage period. Therefore, K foliar sprays from KH2PO4 used for both preharvest treatment and postharvest storage methods maintain the quality and shelf life of cherry tomatoes.