Changes in endogenous gibberellins in plant organs producing and utilizing photosynthates

The distribution of endogenous gibberellin-like substances in individual organs ofZea mays L., cv. CE 250, plants was investigated during the transition from the vegetative to the generative phase of development. The gradient of the content of gibberellin-like substances and photosynthetic activity in leaf segments was followed in different parts of the Jeaves, as well as the changes in the content of gibberellin-like substances in leaf segments during an exposure in the light and in the dark. The gradient of the content of endogenous gibberellin-liko substances in the leaves, in the stem and in the spike is interpreted in terms of possible relationship of these compounds to the regulation of sink — source.