Rootstock vigour and leaf colour affect apple tree nutrition

Nutrient uptake and transport depend on the root system of a tree. Various apple rootstock genotypes may interact fruit tree nutrition. The effect of apple (Malus x domestica Borkh.) rootstocks (M. 9, M. 26, B. 396, P22, P59, P61, P62, P66, P67, Pure 1 and PB. 4) on the mineral nutrition of leaf and fruit was studied in 2013-2015. The leaf and fruit mineral concentration for nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and leaf mineral content for copper (Cu), zinc (Zn), iron (Fe), manganese (Mn) and boron (B) were measured. Apple trees on semi-dwarf M. 26 and dwarf P67 rootstocks accumulated more minerals in leaves and fruits. The highest negative deviation from optimal nutrient content was detected in leaves from trees on super-dwarf rootstock P59. Red-leaved rootstocks accumulated significantly more Ca in leaves and fruits of scion cultivar and determined significantly lower K, N and Mg ratios to Ca. Rootstock vigour had impact only on leaf Ca and Mg. More dwarfing rootstocks determined higher content of Ca and lower content of Mg. More vigorous rootstocks had positive effect on fruit K and P, while dwarfing on K, N and Mg ratios to Ca. Based on rootstock selectivity to accumulate certain minerals, by choosing the right rootstock genotype we can create orchards tolerant of unfavourable soil conditions.