Abstract
Serial segments of internodal stem tissue were isolated from Pisum sativum L. shoots and incubated in a medium containing N6(Δ2-isosopentenyl) [3H]adenine. The recovery of radioactive derivatives separated using HPLC indicated a gradient of cytokinin metabolic activity in the stem. This gradient of activity was found to be greatest at the basal node in young seedlings but was high both at upper and lower nodes in older plants. An attempt to correlate this phenomenon with the basipetally decreasing concentration of indole-3-acetic acid in the stem led to an experiment in which stem segments were pretreated in indole-3-acetic acid solutions before incubating in a medium containing N6(Δ2-isosopentenyl) [3H]adenine. Indole-3-acetic acid was found to have a marked effect on cytokinin metabolism in isolated stem segments. These results are discussed in relation to apical dominance in the shoot.
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King, R.A., Van Staden, J. The metabolism of N6(Δ2-isosopentenyl) [3H]adenine by different stem sections of Pisum sativum . Plant Growth Regul 9, 237–246 (1990). https://doi.org/10.1007/BF00045286
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DOI: https://doi.org/10.1007/BF00045286