Variation in amylose content among Arabidopsis accessions. A, Iodine-stained rosettes. Three-week-old plants were harvested at the end of day, cleared of chlorophyll, and then stained with Lugol’s iodine solution. B, Amylose content of starch. Amylose was detected using an iodine colorimetry-based method in starch from 3-week-old plants harvested at the end of the day. Values are the mean ± sem of n = 5–6 individual rosettes. Those that are significantly different from the reference accession, Col-0 (two-tailed t test, P < 0.05), are indicated with an asterisk (*). C, Total starch content at the end of day (yellow) and end of night (dark blue). Measurements were made on the same batch of plants as B. Values are the mean ± sem of 5–6 individual rosettes. Values that are significantly different from those of the reference accession, Col-0, at each time point (two-tailed t test, P < 0.05) are indicated with an asterisk (*).