Fig. 1: Morphological characterization of vegetative phases of the early heading Chinese cabbage CC-Z16 with round leafy head, the late heading CC-A03 with cylindrical head, and non-heading pak-choi PC-024.

Seedling stage is indicated by “S,” rosette stage is indicated by “R,” folding stage is indicated by “F,” and heading stage is indicated by “H.” For PC-024, stages are indicated by “S,” “R1,” “R2,” and “R3.” In CC-A03, seedling stage is week 2, rosette stage is week 5, folding stage is week 8, and heading stage is week 11. In CC-Z16, seedling stage is week 2, rosette stage is week 4, folding stage is week 6, and heading stage is week 7. In PC-024, seedling stage is week 2, rosette stage R1 is week 4, R2 is week 6, and R3 is week 7.