Starch Changes in Developing and Senescing Tobacco Leaves

The quantitative changes in starch content during the growth and senescence of tobacco leaves have been followed. The starch content was low while the leaves were expanding but rapidly increased after expansion stopped. The maximum was reached when more than half of the original chlorophyll content had gone. The starch content was then reduced rapidly and when the leaf was all yellow there was only a small quantity of starch and this remained when the leaf turned brown.