Fig. 5

Effects of codon-optimized SmAP2-17-overexpression on salt stress tolerance in transgenic Arabidopsis. a qRT-PCR analysis of the expression levels of codon-optimized SmAP2-17-overexpression in WT and transgenic lines Op T-3 and Op T-6 under normal and salt stress (100 mM) conditions. b Statistical analysis of the germination rate of the WT and transgenic lines Op T-3 and Op T-6 at 72 h after sowing under different concentrations of NaCl (75 mM NaCl, 100 mM NaCl, and 150 mM NaCl). c Transgenic lines Op T-3 and Op T-6 had more and longer lateral roots than the WT. d Statistical comparison of the total root length (primary root + [lateral root number × average length of lateral roots]) between WT and transgenic lines Op T-3 and Op T-6. e–h Physiological indices of transgenic and WT Arabidopsis seedlings under normal and stress conditions. The MDA content (e) and antioxidant enzyme activities, including peroxidase (f), catalase (g), and superoxide dismutase (h), were measured in the WT and transgenic lines Op T-3 and Op T-6 under normal and salt stress conditions. Two-week-old seedlings were exposed to 200 mM NaCl for 4 d before the measurements. Data represent the mean of three replicates, and the error bars indicate the SD; *P < 0.05 and **P < 0.01 by Student’s t-test