Abstract
The objective of this study was to examine the effect of different mode of titanium (Ti) fertilization on growth and nutrition by M.26 EMLA apple rootstock (Malus spp.) grown in three soils with diverse physical and chemical properties. Soils were taken from Warszawa, Grojec and Brzezna regions (fruit growing regions) of Poland. The experiment was carried out during 120 days in a greenhouse. The following treatments were applied: soil Ti fertilization at a rate of 2 and 4 mg Ti per plant and four- and eight-times Ti sprays at a rate of 0.5 mg Ti per plant in each spray. Titanium was applied as TiCl4. Plants unfertilized with Ti served as control. Titanium sprays increased levels of this element in leaf and stem tissues. Soil Ti applications had no effect on Ti concentrations in plant tissues except plants grown in Warszawa soil where root tissue had higher Ti status compared to those of control plants. Foliar Ti applications enhanced plant dry matter and levels of phosphorus (P), iron (Fe), manganese (Mn), and zinc (Zn) in leaf tissues only in Brzezna soil. Leaves of plants sprayed with Ti grown in Brzezna soil were greener and had higher concentrations of Fe2+ and chlorophyll than those of control plants. These results suggest that the primary reason for higher biomass in plants sprayed with Ti was higher leaf Fe2+ level, which enhanced chlorophyll synthesis and uptake of P, Fe, Mn, and Zn.