We studied the effect of partial spur leaf removal on fruitlets shedding in 2016. Three treatments were included in the experiment with 2/3, 1/3 and 0 spur leaf area removal. We monitored the fruitlets shedding during the June drop and at the harvest of the remaining fruit, we counted the rest of it. At harvest, the quality parameters of fruits were measured (fruit weight, fruit diameter, firmness (kg/cm²), total soluble solids (°Brix) and maturity index) and the content of the sugars (fructose, glucose, sucrose and sorbitol) and the organic acids (fumaric, shikimic, malic and citric acid) were determined and analysed using HPLC system. In the treatments where 1/3 and 2/3 spur leaf area were removed, the natural fruit drop was greater than in the treatment with no spur leaf area removal. The king flower (K) remained in most cases. While the lateral fruitlets (L1) which were closest to the king fruitlets dropped in the most cases in the treatment where no spur leaves were removed. With a higher proportion of leaf area removal, the fruitlets abscission was more intensive at lower positions (L1-L4). The quality of fruits varied among the treatments. The highest levels of total sugars were measured in apples where we removed 2/3 of the leaf area, while total organic acid were in high levels at 2/3 and 0 leaf area removal. The one-year shoots growth was statistically significant highest in the treatment with no removed leaves.
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