Effect of foliar sprays containing calcium, magnesium and titanium on peach (Prunus persica L) fruit quality

Sprays containing Ca^2+, Mg^2+ or Ti^4+ were applied to peach trees in several combinations. Effects of treatments on the commercial quality of fruits, especially focused on improving their mechanical properties, are discussed. All treatments containing titanium increased tree performance (branch elongation, flowering and fruit set intensities) and fruit size. At harvest, fruits from Ti-treated trees showed improved resistance to compression and penetration, as well as a decrease in weight loss during postharvest storage. A similar response was obtained for external colour, though all treatments seemed to delay somewhat the apparent ripening status. Nevertheless, fruits from Ti-treated trees showed better behaviour in the evolution of colour parameters during storage than did control fruits. Titanium application showed significant increases in iron, copper and zinc concentrations in the peel and calcium concentration in the peel and flesh. This improvement in calcium absorption is explained as a consequence of the beneficial effect of titanium on the absorption, translocation and assimilation processes.