Figure 4.

Auxin Transport Activity in the Wild Type and Mutants.

(A) Auxin transport activity in seedlings. The atmdr1 mutation dramatically impaired auxin transport in seedlings, but the atpgp1 mutation did not. Each assay used 10 seedlings. Values shown are means ±sd of three independent experiments.

(B) Polar auxin transport activity in apical sections of inflorescence. As in seedlings, the atmdr1 mutation dramatically impaired polar auxin transport but the atpgp1 mutation did not. The double mutant was more impaired. WT, wild type. Values shown are means of three independent experiments ±sd.