Thinning and foliar fertilization influence on the yield of Idared apple cultivar

Abstract

The research was conducted during 2010 - 2013 in an apple orchard planted in 2003 with 'Idared' cultivar grafted on M26 rootstock, at distance of 4x2 m. The trees are ruled by thin spindle-shaped crown. We studied the interaction between foliar fertilization and fruit thinning as the main determinants of the quantity and quality of apple fruit. The highest production (49.1 t/ha) was realized at application of 46% urea N in a concentration of 0.6% - when the 75% of the flowers while they fall, 0.9% - when the central fruit blossom has 10 to 12 mm, 1.2% - when the fruits are 25-30 mm in diameter and thinning of fruits by chemical preparation Bioprzerzedzacz SL 060, at a concentration of 0.075% when the diameter of the central fruit blossom is 10 - 12 mm.