Uptake and metabolism of 6-benzylaminopurine in shoot cultures of

Shoots of Gerbera jamesonii Bolus, cultured in vitro were induced to multiply by the addition of 2.22 μ M 6-benzylaminopurine (BAP) to the medium. Shoots growing in the presence of ¹⁴C]-BAP were harvested every 4 days and sub-divided into petioles plus apices, laminae and basal callus. The 3- and 9-glucosides, 9-riboside and a novel compound, the 9-ribosylglucoside were characterised as metabolites of BAP by mass spectrometry. The 9-riboside was the principal metabolite formed initially in petioles plus apicies and callus but further metabolism varied depending on tissue type. After 24 days the major metabolite in the callus was the 9-ribosylglucoside, with only trace amounts of the other metabolites present. In contrast, both 3-glucoside and 9-ribosylglucoside accumulated in petioles plus apices whereas the 3-glucoside accumulated in laminae.