Department of Plant Production, College of Food and Agricultural sciences, King Saud University, Saudi Arabia., department of Pomology, Faculty of Agriculture, Alexandria University, Alexandria, Egypt.
Key words: Putrescine, GA3, 2, 4-D, calcium, peel senescence, Navel orange
Journal of Applied Horticulture, 2012, volume 14, issue 1, pages 56-62.
Abstract: The present study was conducted in 2007/2008 and 2008/2009 seasons in order to extend harvest season and maintain fruit quality for better marketability of Washington navel oranges growing in clay soil by preharvest foliar sprays of GA3, 2,4-D, putrescine and calcium either alone or in combinations. Fruits were harvested on two different harvest dates, the first was at the estimated commercial harvest date (middle December), and the second was late in the harvest season (during February). At both harvesting dates, all spray treatments delayed fruit softening, peel ageing and fruit color break and decreased creasing and fruit drop. Also, fruit TSS, sugars and vitamin C contents increased. The treatments had positive influence on extending harvest season without any deterioration in fruit characteristics. Spraying the different substances in combinations gave better results, especially with putrescine.
