Effects of boron deficiency and calcium supply on the calcium metabolism in tomato plant

Abstract

Tomato plants were grown in water-culture with a different supply of Ca (10, 100 ppm) and B (0, 0.2 ppm), and the effects of B deficiency on the translocation and subcellular distribution of Ca in tomato plants were studied by using45CaCl2 as a carrier of Ca. Boron deficiency slight increased the total Ca uptake by the plant and inhibited the Ca translocation to the upper leaves. The incorporation of45Ca into the cell wall in the upper leaves was increased by B deficiency at both Ca levels. As Ca supply decreased, the distribution of45Ca in the 1N NaCl fraction of the cell wall increased only at 0.2 ppm B. As B supply decreased, the distribution of45Ca in the 0.6N HCl fraction increased at both Ca levels. These results suggest that B deficiency inhibit the translocation of Ca, and induce the abnormal changes of the Ca metabolism in the cell wall.