The activity of deaza- and aza-purine analogues ol cytokinins in gametophore induction in protonema cultures of Funaria hygrometrica

Cytokinin activities of the 1-deaza-, 3-deaza-, l-deaza-8-aza- and of 3-deaza-8-aza-purine analogues of kinetin and of 6-(3-methyl-2-butenylamino) purine were determined in gametophore induction in protonema cultures of Funaria hygrometrica and compared with those of the parent compounds. A relatively high activity of the 1-deaza-anaiogues and very low activity of the 3-deaza-analogues were found. The results confirm the suggestion that the nitrogen in the 3-position of the purine ring is more important with regard to the cytokinin activity of a compound than the nitrogen in the 1-position.