EFFECTS OF POTASSIUM NITRATE SPRAYING ON FRUIT CHARACTERISTICS OF 'MALAS YAZDI' POMEGRANATE

The present research was carried out to investigate the effects of potassium nitrate on pomegranate fruit quality. Treatments were: 1) control, distilled water was used; 2) potassium nitrate 250 mg L-1 plus Tween-20 and 3) potassium nitrate 500 mg L-1 plus Tween-20. All treatments were sprayed on fruits with a diameter of 30 mm. Juice, peel, seed characters, and fruit quality components were evaluated when fruits were harvested. Results indicated that 250 mg L-1 potassium treatment increased juice volume and weight compared with the control and the 500 mg L-1 K treatments. As the potassium nitrate level increased, aril length and diameter decreased. Although there was not a significant difference among treatments on titrable acidity and pH contents of fruits, the highest total soluble solids and vitamin C were obtained in the 250 mg L-1 potassium nitrate treatment when compared with the others. These findings show that applied potassium nitrate significantly influences fruit quality of pomegranate when fruit are in the beginning stages of growth and development.