Absorption and Translocation of Calcium and Phosphorus Supplied to the Top and Root of Tomato Seedlings

Abstract

To evaluate the effect of the foliar application of Ca, the absorption and translocation of Ca were measured after ^<45>Ca was supplied to either surface of the lamina, the stem, the node, or the roots of water-cultured tomato seedlings. The absorption and translocation of ^<32>p were also measured for comparison with Ca. We found that : 1) When Ca was supplied to either surface of the lamina, it was well absorbed and translocated only to the distal end in the applied leaf. Ca was not translocated to other plant organs such as roots, stem, upper leaves or shoot apices. On the other hand, more P was absorbed in the lower surface than in the upper surface of the leaf, and absorbed P was well translocated to all parts of the plant. 2) When supplied at the stem, absorption and translocation .to the upper part of the plant was detected more for Ca than P. 3) When supplied at the node, the amount of Ca absorbed and translocated was the largest in comparison with other plant organs and portions, and absorbed Ca was well translocated to the top portion of the plant and immediately above the supplied leaf. Phosphorus was translocated to all parts of the plant, although the amount was not as high as that of Ca. 4) Both Ca and P supplied at the root were translocated to all parts of the plant. The amount of translocation was higher for P than Ca.