Fig. 4

Cluster analysis of differentially expressed genes during drought treatments. Heat map illustrating the expression profiles of the differentially expressed genes at three time-points (i.e., 3-day drought, 6-day drought, and water recovery). The bars on the left side of represent the 10 different clusters, while the results of the cluster analysis of the gene expression profiles with the K-means algorithm are presented on the right side of (a). Randomly selected differentially expressed genes were analyzed by qRT-PCR. The relative gene expression levels based on the RNA-seq data are indicated by red lines. The letters a, b, and c indicate significant differences according to the Student’s t-test (P < 0.05) (b)