Effects of foliar zinc (Zn) applications on fruit quality of granny smith apple cultivar

Zinc (Zn) is an important micronutrient element that directly participates in protein synthesis in plants and plays a direct or indirect role in the activity of more than 300 enzymes. In plants with zinc deficiency, events such as cell elongation, cell division and differentiation of dividing cells are adversely affected. As a result, the growth of the plant is stopped and the yield and quality are reduced accordingly. This thesis study investigated the effect of Zn applications on leaf of Granny Smith (Malus x domestica Borkh.) apples on semi-dwarf MM111 parents on the yield and quality of apple cultivars depending on different time and application regime on the physical and chemical properties of the fruit. According to experiments based on the design of coincidence parcels, one (Zn1), two (Zn2) and three times (Zn3) Zn applications on leaf were applied after full flowering at a dose of 0.2% Zn (ZnSO4.7H2O) and one month between each application. It was found statistically significant (P <0.05) increases in Zn concentrations of fruits by foliar Zn application. The Zn concentration of the foliar-free fruit was 1.44 ppm, whereas the Zn concentration increased by 155% to 3.67 ppm. It was seen that the Zn concentration of the foliar-free fruit was 1.44 ppm, whereas the Zn concentration increased by 155% to 3.67 ppm. In addition to the increase of fruit Zn concentration by foliar Zn application, significant increases in fruit yield also occurred. According to the control application, the increase of 43.8% in fruit yield occured after Zn applications. The total phenol and total flavonoid contents of the fruits were statistically significantly decreased by application of Zn from the leaves. As a result, it has been found out that there is a significant increase in mineral nutrition level, yield and quality of fruits by means of Zn applications from the leaves.