Effect of Foliar Spray with Ascorbic acid on Some Qualitative Characteristics and Improving Color of Apple Fruit (Malus domestica cv. Red Spur)

Low quality of fruits is one of the most important problems in marketing of apple fruits. Recently the use of organic compounds such as ascorbic acid in order to improve fruit quality has greatly increased. Since little information is available regarding the effects of ascorbic acid on apple fruit quality, the present study was conducted to study the effect of foliar spray with ascorbic acid on some qualitative characteristics of apple fruits.
Material and In this study, the effect of foliar application with different concentrations of ascorbic acid (0, 200 and 400 mg/L) during summer season, was investigated on some fruit quality properties characteristics and color improvement in Red Spur apple cultivar. The experiment was conducted based on randomized complete block design with 4 replications (one tree per replication).
The results showed that foliar spray of ascorbic acid at 200 mg/L concentration significantly increased the amount of fruit TSS and anthocyanin compared to the control. Significant increasing in total acidity, vitamin C, total antioxidant content, total flavonoid and PAL enzyme activity were observed with increasing concentration of ascorbic acid. By increasing the concentration of ascorbic acid, fruit pH was significantly reduced.
The results of this study showed that foliar spray of ascorbic acid probably due to increased level of TSS as a main substrate in the anthocyanin biosynthesis pathway and due to increased PAL enzyme activity as a key enzyme involved in flavonoids biosynthesis pathway such as anthocyanin, led to improve fruit color and qualitative characteristics of Red Spur apple cultivar.