Fig. 3.

Effects of yucasin, an auxin biosynthesis inhibitor, on leaf vein development in G. gynandra. Plants were grown in half-strength Kimura B nutrient solution with or without yucasin. (A) Vein densities in untreated, DMSO-treated, and yucasin-treated leaves. DMSO was used to dissolve yucasin. Each vein density is given in mean value ± SD (four biological replicates; Dataset S6). **P < 0.001, Student’s t test. (B) Vein pattern of the fifth newly developed leaf (∼2.5 cm long) from a plant grown in a control (untreated) solution. (C) Vein pattern of the fifth newly developed leaf (∼2.5 cm long) from a plant grown in a solution containing 75 μM yucasin. (B and C) Red arrows indicate the highest-order veins. (D and E) Cross-sections of the fifth leaf (∼2.5 cm long) grown in a control solution (D) or in a solution containing 75 μM yucasin (E) were stained by toluidine blue stain. Yucasin reduced the number of higher-order veins. (Scale bar: 100 μm.)