Figure 3.

Effects of oxygen deprivation on the survival of nip2;1 T-DNA insertional mutant seedlings. A, Seven-day-old, vertically grown seedlings of WT (Col-0) and nip2;1 were subjected to a 8 h of argon gas treatment and were allowed to recover under normal oxygen conditions for 72 h prior to assessing survival. Scale bar = 1 cm. B, PS II maximal quantum yield [QY_max (F_v/F_m)] was calculated from chlorophyll fluorescence analysis of 7-d-old WT (Col-0, black circles) and nip2;1 mutant (red triangles) seedlings treated with 8 h argon (hypoxia, solid lines) or air control (normoxia, dashed lines). Error bars represent the standard error of mean (sem) of five biological experiments. *P < 0.05 based on Welch’s unpaired t test. C, Box and whiskers plot showing the survival of 7-d-old WT, nip2;1, and two NIP2;1:GFP complementation seedling lines after 8 h argon treatment, represented as percentage seedling survival as described by (Licausi et al., 2010). Each data point represents one biological replicate with the median value indicated as a solid line within in each box. Statistical significance was assessed by multiple comparisons by one-way ANOVA analysis. (^****P < 0.0001 for nip2;1 compared to WT and both complementation lines; ns, not significant).