The effect of bicarbonate induced Fe chlorosis on mineral content and Ca45 uptake of apple seedlings

Abstract Apple seedlings (Malus domestica) cv ‘York Imperial’ were used as test seedlings in solution culture experiments on the effect of added bicarbonate (HCO− 3 at 61 or 122 ppm) over two K levels (78 or 156 ppm K). Added HCO− 3 not only induced Fe chlorosis but also reduced plant growth. Inclusion of higher K in the nutrient solution containing HCO− 3 tended to alleviate both the growth and reductions in leaf fe concentration. Analysis of upper leaves generally showed increased levels of P, K, Ca, Mg and B compared to control seedlings while Fe was significantly reduced. These trends were modified slightly depending upon the specific HO− 3 or K level. Root nutrient levels generally followed patterns similar to leaves. A concurrent study using similar treatments was conducted with the seedlings exposed to 45Ca. After an eight day exposure period HCO− 3 at either level (61 or 122 ppm), with or without higher solution K, significantly decreased the amount of 45Ca in upper leaves.