تأثير الرش الورقي بكبريتات البوتاسيوم وبعض مضادات الأكسدة في إزهار وإثمار أشجار البرتقال صنف فالنسيا (Citrus sinensis L. var.Valencia)

Abstract

The experiment was carried out during the 2019/2020 season in a citrus orchard in Myaar Shaker country south of Tartous city on Citrus sinensis L.var.Valencia trees to study the impact of foliar spray with salicylic acid (150 mg/l), citric acid (500 mg/l), potassium sulfate (2500 mg/l) and ascorbic acid (500 mg/l) in the flowering and fruiting of Valencia orange trees. Foliar spray treatments were applied three times according to the phenological stages of trees The first spraying was when flowering was complete, the second spraying was at the end of the decade and the beginning of fruiting growth, and the third spraying was a month and a half after the second spraying. The results showed that the treatments significantly raised fruit set percentage and reducing fruit fall, and increasing production and productivity compared to the control. Salicylic acid and citric acid spray resulted in the highest percent of fruit set (74,64 &72.8%) was superior to control (58.15%), also Salicylic acid treatment gave the best results in terms of production and productivity  (177 kg/tree) & (7067 kg /dunum ) followed by ascorbic acid (174 kg/tree) & (6973 kg / dunum) compared to control (110 kg/tree) & (4382 kg /dunum). The results showed that organic acids sprays were more effective than potassium sulfate spray in term of the studied parameters.