Abstract
An attempt was made to study sugar transformations in sunflower leaf disks as an approach to the problem of starch synthesis. The transformation of the C
14-labeled glucose was followed by chromatography and an examination of a radioautogram series and determination of the activities in the synthesized compounds. From the data obtained, it is suggested that there are at least two mechanisms for amylose synthesis. While a phosphorylating mechanism might operate in plants which form little sucrose, a transglucosidizing mechanism could well build amylose in plants that produce sucrose in large quantities. In both cases, the Q-enzyme probably utilizes the available amylose to form amylopectin.