Meiocytes of cycb3;1/ − mutants are hypersensitive to oryzalin. (A) Scheme of live-cell imaging of male meiocytes treated with oryzalin. (B–G) Time points of meiotic progression in meiocytes expressing TagRFP:TUA5 in WT (B1–B6) and cycb3;1/− (C1–C6) with DMSO (from Video 8); WT (D1–D6) and cycb3;1/− (E1–E6) with 200 nM oryzalin (from Video 9); and WT (F1–F6) and cycb3;1/− (G1–G6) with 500 nM oryzalin (from Video 10). Scale bar, 10 µm. (H) Spindle length at metaphase I of meiocytes from at least three different anthers of WT (n = 28) and cycb3;1/− (n = 23) treated with DMSO; WT (n = 22) and cycb3;1/− (n = 25) treated with 200 nM oryzalin; and WT (n = 23) and cycb3;1/− (n = 20) treated with 500 nM oryzalin. Level of significance (*, P < 0.05; **, P < 0.01; ***, P < 0.001) determined by one-way ANOVA followed by Tukey’s test. (I) Number of meiotic products (tetrads or unreduced gametes) of meiocytes from at least three different anthers of WT (n = 28) and cycb3;1/− (n = 23) treated with DMSO; WT (n = 22) and cycb3;1/− (n = 25) treated with 200 nM oryzalin; and WT (n = 23) and cycb3;1/− (n = 20) treated with 500 nM oryzalin.