Figure 2. (A) ROS levels in sperm determined by flow cytometry with DCFH-DA after 1-h gibberellin treatment. (B) Spermatozoon plasma membrane phosphatidylserine externalization, determined by flow cytometry with an Annexin V-FITC apoptosis detection kit. (C–D) The relative protein levels of the apoptotic markers BAX and P53 in sperm were detected by immunocytochemistry and quantified based on the relative fluorescence intensity. (E–F) The relative protein levels of BAX and P53 in sperm were detected by Western blotting. The results are presented as the mean ± SEM.