Different endogenous cytokinins between male and female Mercurialis annua L.

The endogenous pool of cytokinin metabolites during sexual differentiation of Mercurialis annua L. was studied with a computerized gas-chromatography-mass spectrometry system. Certain metabolites were common to both sexes: ribosides (isopentenyl-adenosine, ribosylzeatin) and the nucleotide of I6-Ade. Zeatin could be detected only in females while its nucleotide was present in males. The results were obtained with differentiating apices and whole plants. The high Z concentration and the low level of its nucleotide are related to the absence of two dominant complementary genes, determining maleness. Study of the regulation of cytokinin metabolism now seems possible.