Fig. 4

Scanning electron microscopy of wild-type and sa1 anthers at binucleate and mature pollen grain stages. (a) and (b) The epidermal surfaces of a wild-type (a) and sa1 anthers (b) at the binucleate stage. Bar = 250 μm. (c) and (d) Enlarged detailed view of the epidermal surfaces of anthers in wild type (c) and sa1 (d) at the binucleate stage. Bar = 20 μm. (e) and (f) Many mature pollen grains are visible in wild type (e), but none are visible in sa1 (f) at the mature pollen grain stage. Bar = 500 μm. (g) to (j) The outer (g) and inner (i) surfaces of wild-type anthers compared to the outer (h) and inner (j) surfaces of sa1 anthers. The outer surface of the sa1 anther is glossy (h), and no Ubisch bodies are visible on the inner anther surface (j). Bar =10 μm in (g) and (h), 5 μm in (i) and (j)