Fig. 7

PtoNF-YC9 positively regulated poplar tolerance to salt stress is dependent on the ABA signaling pathway. A The salt tolerance of 45-day-old PtoNF-YC9-RNAi, WT, and PtoNF-YC9.1-OE poplars in soil treated with 300 mM NaCl solution. B The MDA content and EL in the poplar leaves (A) after salt treatment. C The Na⁺ content of the leaves of poplars (A) after salt treatment. D The expression levels of PtoHB7, PtoERD7, PtoCIPK21, and PtoPUB79 in the PtoNF-YC9 overexpression, RNAi, and WT poplars with or without salt stress by qPCR, respectively. Letters above bars represent statistically significant differences between groups (P < 0.05) as determined by one-way ANOVA Duncan’s test. E The salt tolerance of PtoNF-YC9-RNAi, WT, and PtoNF-YC9.1-OE in the WPM solid medium supplemented with 150 mM NaCl or 150 mM NaCl plus 10 μM FLU. F The MDA content and EL of the poplar leaves in WPM solid medium with 150 mM NaCl. G The MDA content and EL of the poplar leaves in WPM medium with NaCl and FLU. The means ± s.d. of all data from at least three biological replicates are shown. Asterisks indicate statistically significant differences (two-sided Student’s t test, **P < 0.01, *P < 0.05, ns = not significant)