OSR2 acts redundantly with ARL . (A, B) Morphology and the size of third leave of 26-day-old WT, osr2, ARLi, and osr2 ARLi (L6 and L8) plants. At least five fully-expanded leaves of each genotype were used for determination of the leaf size; the data are shown as mean values ± SE; Student’s t-test: *P < 0.05, ***P < 0.001. Bars, 2 mm. (C, D) The epidermal cell area and estimated cell number of the third leave described in (A). Data were from at least five leaves of each genotype and are shown as mean values ± SE; Student’s t-test: *P < 0.05, **P < 0.01.