Differential expression analysis between control and drought stress. Data points at the upper and lower side of the slope line represent up- and down-regulated miRNAs in panel (a), respectively. The changes in miRNAs for up- and down-regulated ones are greater than 1.5-fold. Other miRNAs include those that are not responsive to drought stress and those changes induced by drought stress at p > 0.05. Expression of control and drought stress was normalized on the basis of 1 M reads. Differential expression of known miRNAs in response to drought stress is shown in panel (b). The positive and negative values mean miRNAs whose expression was stimulated and suppressed by drought stress, respectively. * and ** mean significant difference between control and drought stress at 0.01 < p ≤ 0.05 and p ≤ 0.01, respectively. The relative expression level of miRNAs measured by RT-qPCR in response to drought stress is shown in panel (c).