Studies on the mobility of calcium in plants

Abstract

Calcium taken up by the roots is initially distributed around the plant via the xylem. Once deposited in organs such as leaves, it is re-distributed either not at all or with difficulty, and has hence been regarded as “phloem immobile”. Two different experimental systems were used to investigate the mobility of C. One involved the mobility of Ca in germinating pea seeds and the other, the movement of Ca in the xylem of pieces of woody stems. Pea seeds generally have less Ca then P, K or Mg and a high proportion of this Ca is located in the testa. There is a wide variation in mineral content of pea seeds, and it is shown that peas at either end of the pod have more Ca than those in the middle. Such a pattern is not found with K or Mg.