Embryonic control of isocitrate lyase activity in cotyledons of germinating soybean.

The activity of isocitrate lyase (EC 4.1.3.1) in the cotyledons of germinating soybean is controlled by the embryonic axis. Plant growth regulators like gibberellic acid, indole acetic acid and 2,4 dichlorophenoxy acetic acid are able to increase the enzyme activity in cotyledons of whole seedlings but not in dissected cotyledons. The control of induction of the enzyme activity during germination by the embryo could be mediated by the elaboration of kinetin.