Figure 2.

More than additive increases in shoot and root growth by crossing P10-CKX3 plants with BRI1-overexpressing plants. A and B, Shoot phenotype of plants grown under in vitro conditions for 21 d. A, Rosette fresh weight. Photographs were taken from the rosettes of the wild type (Col-0), the heterozygous parents, and the cross grown for 18 d in vitro. B, Blade area of cotyledons (0) and leaves 1 to 10 calculated from leaf series. C to F, Root growth of wild-type plants and plants overexpressing P10-CKX3 and/or BRI1. Plants were grown on vertical plates under in vitro conditions for 9 d. C, Primary root length. D, Lateral root number. E, Total root system length. F, Root system of 9-d-old plants. From left to right: Col-0, BRI1, Col-0×BRI1, P10-CKX3×BRI1, Col-0×P10-CKX3, and P10-CKX3. Values expected if additive were calculated as the sum of Col-0×P10-CKX3 and BRI1×Col-0 minus Col-0. Asterisks indicate values significantly different from the wild type (*) and from the value expected for an additive effect (**) by Student’s t test (P < 0.05 [A and B] and P < 0.01 [C–E]). Error bars indicate se (n ≥ 16 [A and B] and n ≥ 23 [C–E]).