Effect of Different Calcium Chloride Application Methods and Macro Elements Fertilizers (Nitrogen, Phosphorus and Potassium) on Fruit Quality and Postharvest Life of Hayward Kiwi Fruit

The correct management of kiwi fruit tree nutrition can affect an increase in postharvest life of kiwi fruit. At this research, based on randomized complete block design with 10 fertilization treatments, the effect of different stages of foliar spraying CaCl2 (August to October) and different amounts of urea, triple superphophate and potassium sulphate on kiwi fruits in a kiwi orchard located at Astaneh Ashrafieh, Guilan Province, Iran, was investigated. The traits including fresh and dry weight, acidity, percent of dry matter, the brix and firmness of fruit, nitrogen, phosphorus, calcium of fruit in harvesting time; and fruits firmness and brix in 60 and 120 days after keeping fruits in storage (temperature 0 ±0.5ºC and 90-95% moisture) were measured. Results showed that the dry matter percent in treatments of five stages foliar spraying calcium was significantly more than control. The brix in the control treatment was 2-2.3 degrees more than in the treatment of five stages of foliar spraying with Ca. The highest concentration of calcium was observed in the treatments of three stages foliar spraying with Ca. The highest fruit firmness obtained in four and five foliar spraying Ca treatments and the lowest firmness in control treatment. Decreasing of fruit firmness during the time in four and five foliar spraying Ca treatments was lower than control. Results indicated the influence of different levels and periods of macro elements fertilizers application with foliar spraying of calcium on the quantities and qualitative promotion of kiwifruit in comparison to traditional fertilization.