Fig. 9

Relative expression levels of 8 RNA helicase genes in response to abiotic stresses detected by qRT-PCR. The abiotic stress treatments include cold (4 °C), heat (42 °C), salt (200 mM NaCl) and drought (200 mM PEG4000). The expression levels at 0 h were normalized to 1, and the Y-axis delineates the fold changes of relative expression comparing with 0 h. Bars represent the mean of three biological replicates ± SE. The two-fold threshold is presented by a dotted line. Values are presented relative to untreated plants (0 h). Asterisks indicate a significant difference (P < 0.05) between untreated and treated plants