EFFECTS OF PARTIAL ROOTZONE DRYING AND DEFICIT IRRIGATION OF 'GRANNY SMITH' APPLES ON FRUIT QUALITY DURING STORAGE

The effects of partial rootzone drying (PRD), deficit irrigation (DI) and control irrigation (CI) on fruit quality during storage of ‘Granny Smith’ apples were studied during a two-year period. Trees were planted in 120-L plastic pots. Fruits achieved earlier maturing at DI treatment, compared with fruits from PRD and CI treatments. Regulated drought has a positive effect on fruit firmness and weight loss during storage. After six months of cold storage, the highest decrease of flesh firmness was found in fruits from CI treatment. Effect of irrigation on changes in contents of soluble solids and total acids during storage were not found. Positive effect of DI on fruit firmness, compared with PRD, was not determined. The weight loss on PRD and DI was similar. Positive effects of DI on fruit storage were not found compared with PRD. Contrary, PRD showed good effects on fruit size and yield, compared with DI treatment.