Fig. 2

Sampling diagram and transcriptomic data quality analysis. a The cartoon showed sampling time points and regions of internode. The maize was treated with 10 μM COR when the 9th leaf was fully expanded. The fixed region (F, apical 1 cm of the internode) of 7th internode, and the meristem region (M, basal 0–1 cm between internode) and elongation region (E, basal 1–2 cm between internode) of 9th internode collected in 1st, 2nd, and 4th day later after COR treatment. b Principal component analysis (PCA) of 18 samples. c to e The region-specific expression genes mainly expressed in the region of fixed (c), meristem (d) and elongation (e) region. The region of fixed region, meristem region and elongation are display in light yellow, blue and green, respectively. f and g The expression of COR-induced genes. These genes are related to plant defense (f) and JA pathway (g) were showed. *: 0.01 < p-value < 0.05; **: 0.001 < p-value < 0.01; ***: p-value < 0.001