Figure 2.

Response of MdBBX7 transgenic plants to drought. A, Morphological characteristics of GL-3 and MdBBX7 transgenic plants after drought stress. Bars = 5 cm. Three-month-old MdBBX7 RNAi and OE transgenic plants and GL-3 were withheld from water until soil volumetric water content reached to 0% and then rewatered for 7 d. B, Survival rate of the plants shown in (A). Asterisks indicated values significantly different between the transgenic lines and the GL-3. C–F, Physiological parameters of GL-3 and MdBBX7 transgenic plants after drought stress. Plants were withheld from water until soil volumetric water content reached to 5%. C, Leaf ion leakage. D, H₂O₂ content. E, POD activity. F, CAT activity. Asterisks indicated values significantly different between the transgenic lines and the GL-3 in each group (Control and Drought). Data are means ± sd (n = 3 in (B), 8 in (C), 5 in (D)–(F)). One-way ANOVA (Tukey’s test) was performed and statistically significant differences were indicated by *P < 0.05, **P < 0.01, or ***P < 0.001.