Effect of salt stress on Fv/Fm of rice seedlings. Under salt stress, lower Fv/Fm values were observed in wild-type seedlings, but no significant changes in Fv/Fm levels were observed in OsCYP2 transgenic rice lines. Ten-day-old rice seedlings of wild-type or OsCYP2-transgenic lines were used. Ten-day-old rice seedlings were treated with 200 mM NaCl for 24 h. Fluorescence from red to pink color represents values from minimal to maximal readout. Each value is the mean ± S.E. of six treatments. Identical letters above a pair of bars indicate there is no statistically significant difference among the transgenic lines at the p = 0.05 level according to Duncan's multiple range test.