Fig. 1.

LFS and auxin response maxima direct tomato leaf initiation. (A) A 5.5-wk-old WT (Left) and lfs (Bottom Right) tomato. (Scale bar: 5 cm.) (Inset) A close-up of the apex of a 15-d-old lfs seedling. as, axillary shoot; c, collar-like structure; h, hypocotyl. (B) A 9-d-old lfs seedling in which the SAM starts to protrude from the collar-like structure surrounding it. (C and D) SEM images of vegetative WT (C) and lfs (D) apices. (E) WT apical meristem bearing one incipient and one visible primordia (P₀ and P₁, respectively). (F) lfs meristem. (G) TIBA-induced pin. Dashed lines in E–G mark the apex tissue, sampled for gene expression analyses. Note the proximity of trichomes to the SAM in D and F, marked by the arrowhead. (H–J) Three-dimensional reconstructions of live TCS:YFP apices captured by a light sheet microscope. (H) WT. (I) lfs. (J) TIBA pin. (Scale bars in C–G: 100 µm.)