Fig. 4. Timing of axillary shoot initiation in wild type, max1-1 and max2-1. Series of transverse sections of individual shoots grown in short photoperiods for 36 days were prepared and axillary shoot development at consecutive node positions was scored into three stages. (A-C) Sections from wild-type shoots, showing the developing axillary shoots (arrowheads) illustrating the stages scored. Scale bars: 100 µm. (A) Stage 1: axillary cell divisions at the base of a developing leaf, visible above the insertion point into the shoot axis. (B) Stage 2: axillary meristem bulging out from the base of the subtending leaf; the angle with the adaxial side of the leaf is at least 45°. (C) Stage 3: first axillary leaf primordium separated from the axillary shoot meristem by a cleft. (D) Node number from the shoot apex at which the three early stages of axillary shoot development first occurred in wild type (wt), max1-1 and max2-1. Circles represent the median, bars extend between the minimum and maximum observed node number of first occurrence of each stage. Number of shoots examined: wild type n=9; max1-1, max2-1, n=11.