Fig. 5

Mature pollen analysis in FLA14 knockout mutant (fla14) and overexpression (OE) transgenic Arabidopsis plants. a, f, k Scanning electron micrographs of a wild-type (WT) anther (a), a fla14 anther (f), and an OE anther (k) at the time of dehiscence. b, g, l Scanning electron micrographs of mature pollen grains in WT (b), fla14 (g), and OE (l) plants. l Arrows indicate the aborted pollen grains that have a collapsed appearance. c, h, m Alexander staining of mature pollen grains in WT (c),fla14 (h), and OE (m) plants. The unviable pollen grains are dyed greenish black. d, e, i, j, n, o 4’,6-diamidino-1-phenylindole (DAPI) staining of mature pollen grains in WT (d), fla14 (i), and OE (n) plants. e, j, o The corresponding bright field images. n, o Arrows indicate the aborted pollen grains with no detectable nuclei. p-u Calcofluor fluorescent white staining of mature pollen grains in WT (p), fla14 (r), and OE (t) plants. q, s, u The corresponding bright field images. t, u Arrows indicate the aborted pollen grains with no detectable calcofluor white fluorescence. v Pollen abortion frequencies in WT and OE plants. The values are the mean ± standard SD. Asterisks indicate significantly different means (p < 0.01) using one-way ANOVA. Scale bars = 100 μm (a, c, f, h, k, m); 20 μm (b, d, e, g, i, j, l, n-u)