Translocation and the control of photosynthesis in sugar beet.

Evidence is presented that the size and activity of "sinks" for the products of photosynthesis exert a large measure of control over carbohydrate levels in the leaves of the sugar beet plant. Further data is presented to show that a correlation exists between the level carbohydrate in the leaf and the rate of photosynthesis. The rate of photosynthesis can thus be linked directly to the "sinks" of the plant by their ability to control rates of translocation from leaves.