Mineral composition of leaves and fruits of apple 'Fuji' on different rootstocks in the region of Sao Joaquim-SC

This work evaluated the mineral composition of leaves and fruits of apple (Malus domestica Borkh) 'Fuji' on different rootstocks. The experiment was conducted from 2008 to 2011 in the municipality of Sao Joaquim (SC). The treatments evaluated rootstocks: CG.008. CG.24, CG.56, CG.058, CG.210, CG.213, CG.757, CG.814 and CG.969 of the American series Cornell Geneva (CG); JM.2 and JM.7 of the Japanese series Japan, Morioka (JM); and M.7, M.9 and M.26 of the English series. EMLA (M). The experimental design was randomized blocks with four repetitions. Annually, the leaves were collected for the chemical analysis. Only in the years 2009 and 2010, the fruit samples were collected to determine nitrogen (N), phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg). The leaf Ca content differed between rootstocks, especially for CG.213 and CG.969, which presented a higher content of the nutrient. How ever, there were no differences between rootstocks in terms of Ca content in the fruit, which confirms the low ratio between the contents in leaves and fruits. Ratios between nutrients, mainly (K+Mg)/ Ca, are more sensitive to the Ca content to discriminate groups of rootstocks about possible risk of physiological disorders in the fruits.