Auxin resistance phenotype of MtCDC16. A, Root growth assay for auxin resistance. Inhibition of root growth in the presence of 0.5 μm 2,4-D was assayed in control (gusi) and Mtcdc16i roots. B, Quantitative RT-PCR analysis to estimate the transcript abundance of TC106907 and TC101963 in gusi and Mtcdc16i (moderate) roots in the presence and absence of 5 μm 2,4-D. In A and B, each point represents the mean of three replicates with error bars representing the sd.