Micrographs of Wt and sbe1a mutant starch samples. A. Scanning electron micrographs of native starch from Wt (left) and sbe1a mutant (right). Scale bars represent 10 μm at the top of the graphs. B. Scanning electron micrographs of residual starch after 16-h α-amylase digestion from Wt and sbe1a mutant. Scale bars represent 10 μm, 5 μm, or 1 μm at the top of the graphs. C. Bright field (left) and polarized light (right) micrographs of native Wt and sbe1a mutant starch. The specimen were stained with 0.04% iodine and viewed within 5 min. Arrows point to dark stained granules.