Green Means Go: The Role of Pigments in Photosynthesis

I. Abstract The level of photosynthetic activity as determined by the presence of starch stores was measured for pigmented leaves of seven plant species. The plants were exposed to morning sunlight, then the leaves were picked and pigments extracted by boiling the leaves in an 80% ethyl alcohol solution. A potassium iodide solution was used to stain the starch stores dark blue, and the levels of starch accumulation were compared with leaf color. The highest levels of starch accumulation were found in the green chlorophyll regions, followed by the orange-tored carotenoid regions. The violet-red and pink anthocyanin regions, while expected to be free of starch accumulation, were found to have low levels of starch storage. These regions may include carotenoids or chlorophyll whose pigment was masked by the presence of the anthocyanins, and levels of pigments may be varied due to the different species of plants used.