RETARDATION OF RUTAB DEVELOPMENT OF ‘’BARHI’’ DATES AND ENHANCING BUNCH RIPENING UNIFORMITY BY PREHARVEST TREATMENTS WITH CALCIUM AND ANTIETHYLENE COMPOUND

Abstract

“Barhi” date fruits are highly valued by the consumers especially at full maturity or the bisr stage. At the full yellow coloration, the fruit is not stringent, crispy and sweet. Thus, research attempts have been focusing on safe and feasible treatments that could be adopted on the field scale. In this study, the treatments included antiethylene (AVG) at 25 ppm, AVG at 50 ppm, AVG at 25 ppm+ calcium chloride 2% (W/V), AVG at 25 ppm + calcium sulphate 2% (W/V), AVG at 50 ppm + calcium chloride 2% (W/V), AVG at 50 ppm + calcium sulphate 2% (W/V), calcium chloride 2% (W/V), and calcium sulphate 2% (W/V). Treatments were conducted by a hand sprayer until the runoff point. The spray was done at the end of August during the two seasons 2017 and 2018 respectively. Bunches of each treatment were harvested at the commercial harvest on October 22 and Sep 4 during the two seasons 2017 and 2018. The data proved that AVG alone whether at 25 or at 50 ppm delayed the progress towards the rutab stage. In other words, such treatments alone or when combined with CaCl2 at 2% extended the bisr stage and even reduced the full rutab (full ripening) stage. Electrolyte leakage of dates was significantly reduced by many treatments especially the combinations of AVG at 25 or at 50 ppm plus CaCl2 in both seasons. However, such former combinations resulted in reducing carotene content in dates as compared with the control. In conclusion, this study proved the possibility of controlling the ripe of “Barhi” dates while reducing their loss by safe treatments.