PtrWRKY75 overexpression enhanced WUE by reducing transpiration
Previous studies have suggested that ROS accumulation in leaves may cause stomatal closure (Song et al. , 2014; Sierla et al. , 2016), thereby reducing transpiration and improving the WUE of plants (Yoo, C.Y et al ., 2009; Yoo, C.Y et al ., 2010). The photosynthesis–light curve showed that photosynthesis was similar in the OE lines and WT (Figure 4A). The stomatal conductance (G s) was significantly lower in the OE lines than in WT (Figure 4B). The leaf transpiration rate was about 30% lower in the OE lines than in WT (Figure 4C). As a result, the instantaneous WUE (photosynthesis/transpiration) values of the OE lines were significantly higher than those of WT (Figure 4D). The vapor pressure deficit (VPD) showed no significant difference between the OE lines and WT, indicating that VPD was not a factor in the reduced transpiration rate of the OE lines (Figure 4E). In general, overexpression of PtrWRKY75 enhanced WUE by reducing the transpiration rate.