Figure 6.

35S:ARR1-SRDX plants are less sensitive to cytokinin. A, Chlorophyll retention in dark-incubated leaves by cytokinin. Fully expanded leaves were excised from 24-d-old plants and floated for 10 d in the dark on water supplemented with various concentrations of cytokinin before the chlorophyll concentration was determined. Time 0 indicates the chlorophyll concentration at the beginning of the experiment. B, Cytokinin sensitivity of primary root elongation. Root elongation was measured for each line between 4 and 9 DAG. The root elongation of each line is expressed as a percentage of its DMSO control. The original data for the transgenic lines were significantly different from the wild-type data, with 0.001 < P < 0.01 as calculated by pairwise Student's t test. C, Cytokinin sensitivity of lateral root formation. The number of lateral roots was determined following growth on vertical plates for 9 DAG. The number of lateral roots between the wild type and the transgenic lines was significantly different (P < 0.01). Error bars represent sd (n ≥ 15). ARR1-S-8 and ARR1-S-10 are two independent lines of 35S:ARR1-SRDX transgenic plants.