The Effect of Copper Supply on the Senescence and the Retranslocation of Nutrients of the Oldest Leaf of Wheat

Abstract

The contents of Cu, N, P, K, Zn, Mn and Ca were followed during the life of the oldest leaf of wheat plants (Triticum aestivum L. cv. Gamenya) grown at deficient and sufficient supplies of Cu. At both levels of Cu, the Cu content of the oldest leaf behaved in a similar way to the contents of N and Zn, which declined markedly during leaf senescence. By contrast to Cu the P and K contents declined markedly, prior to leaf senescence, whereas the Ca and Mn contents increased throughout the life of the leaf and did not decline during leaf senescence. Interactions among Cu supply, the supply of other nutrients (e.g. N), and leaf senescence account for the variable mobility of Cu in wheat. Similar interactions between nutrient supply and senescence may explain contradictory reports on the redistribution of other nutrients which are variably mobile in plants.