Ecophysiology is de‰ned as the in¬uence of environmental factors on physiological processes of plants. Ecophysiology is one of the most important topics in understanding the in¬uence of environmental factors on the growth and development of crop plants. Environmental factors that affect the growth and development of plants are climate (precipitation, temperature, and solar radiation) and soil (physical, chemical, and biological). Part of the roots of plants such as sugar beet (Beta vulgaris L.), cassava (Manihot esculenta Crantz), sweet potato (Ipomoea batatas L. Lam.), and carrot (Daucus carota L.) are speci‰cally adapted to store products that are photosynthesized in the shoot. According to Gregory (2006), the products are synthesized aboveground and transported to the root in the phloem where they reside until needed to complete the life cycle. In biennials such as carrot and sugar beet, the storage organs are frequently harvested for human use before the life cycle is complete, but if allowed to mature, the stored materials are retranslocated to the shoot where they are used to produce ¬owers, fruits, and seeds. The development of storage roots is similar to that of nonstorage roots, except that parenchyma cells predominate in the secondary xylem and phloem of the storage roots (Gregory, 2006).