Delphinidin

- Food-Storage Roots
Most roots and stems store some food, but in certain plants, the roots are enlarged and store large quantities of starch and other carbohydrates, which may later be used for extensive growth. In sweet potatoes and yams, for example, extra cambial cells develop in parts of the xylem of branch roots and produce large numbers of parenchyma cells. As a result, the organs swell and provide storage areas for large amounts of starch and other carbohydrates. Similar foodstorage roots are found in the deadly poisonous water hemlocks, in dandelions, and in salsify. In carrots, beets, turnips, and radishes, the food-storage tissues are actually a combination of root and stem. Although the external differences are not obvious, approximately 2 centimeters (0.8 inch) at the top of an average carrot is derived from stem tissue that merges with the root tissue below.

- Water-Storage Roots
Some members of the Pumpkin Family (Cucurbitaceae) produce huge water-storage roots. This is particularly characteristic of those that grow in arid regions or in those areas where there may be no precipitation for several months of the year. In certain manroots (Marah), for example, roots weighing 30 kilograms (66 pounds) or more are frequently produced, and a major root of one calabazilla plant (Cucurbita perennis) was found to weigh 72.12 kilograms (159 pounds). The water in the roots is apparently used by the plants when the supply in the soil is inadequate.