Starch degradation in submerged Arabidopsis plants. A, Quantitation of starch in rosette leaves of Arabidopsis Col-0 plants that were submerged at the end of the light period. Submergence was carried out in the dark; see Supplemental Figure S1 for oxygen content in the water. Data are mean ± sd of three biological replicates (ANOVA, P < 0.05). B, Iodine staining of starch in plants from the experiment described in A. C, Sugar content in rosette leaves of Arabidopsis plants that were submerged at the end of the light period. Submergence was carried out in the dark. Sugars were quantified at the end of the day (Time 0) and after 4 and 12 h of darkness/submergence. Data are mean ± sd of five biological replicates, n = 3 for sugars (ANOVA, P < 0.05). D, Quantitation of starch in rosette leaves of Arabidopsis sex1-1 mutant. Treatments are as in A. E, Iodine staining of starch in plants from the experiment described in D. F, Sugar content in rosette leaves of Arabidopsis sex1-1 plants (see C for details). Data are mean ± sd of five biological replicates for starch, n = 3 for sugars (ANOVA, P < 0.05).