The binding interactions between cytokinin analogs and ribosomes of a dioecious plant are studied. Molecular interactions between cytokinins and ribosomes have been investigated and compared to male and female by using radioactively labeled 6-benzylamino [8-^(14)C] purine as a probe. Further results on the binding of benzylaminopurine to male ribosomes in connection with kinetin, 6-furfurylaminopurine, and their respective ribosides are reported presently.