Effect of Pre-harvest Calcium Chloride and Chitosan Treatments on Fruit Quality of 'Benica' Sweet Cherry

In this study, the effects of pre-harvest application of calcium chloride and chitosan, separately and in combination, on fruit quality characteristics of `Benica' sweet cherry fruit during postharvest storage was investigated. Six year old 'Benica' sweet cherry plants were foliar sprayed once with 0.5% calcium chloride at 30 days after full bloom. Chitosan was foliar sprayed at 100 ppm, alone or in combination with 0.1% calcium chloride five times at five day intervals starting from 30 days after full bloom. Untreated plants served as control. Fruits were harvested at 53 days after full bloom, packaged in transparent plastic boxes, and stored separately at either 4 degrees C or 22 degrees C. The fruit quality characteristics were evaluated after 5 and 7 days of storage. The cherry fruit cracking ratio was recorded after immersed the fruit in water for 24 hours at room temperature (25 degrees C). Fruit firmness and soluble solids content were higher with 0.5% calcium chloride and 100 ppm chitosan, alone or in combination with 0.1% calcium chloride, compared to the control. The fruit cracking ratio was lower with the combination of 0.1% calcium chloride and 100 ppm chitosan. Based on scanning electron microscope images of 'Benica' sweet cherry fruit skin, chitosantreated fruit had smoother skin than the control, which may be due to the formation of a protective layer formed by chitosan on the fruit skin. In summary, pre-harvest treatment of calcium chloride and chitosan was effective in reducing the cracking and improving the firmness of 'Benica' sweet cherry fruit.