Figure 5.

Exogenous ATP inhibits basipetal auxin transport in Arabidopsis and maize roots. A, Basipetal auxin transport in Arabidopsis roots was allowed to precede in darkness for 5 h, at which time the [³H]IAA in a 5-mm root section 1 mm back from the tip was quantified by scintillation counting. Values represent average ± se. B, Basipetal auxin transport in maize roots was allowed to proceed in darkness for 4 h, at which time the [³H]IAA amount in the receiver agar block was quantified by scintillation counting. The experiment was repeated at least four times. The data represent the average ± se (n > 16).