What stores starch reserves to support the vine through dormancy?

• A. Sugar in leaves
• B. Starch in the roots, trunk, and branches
• C. Minerals in the trunk
• D. Moisture in roots

Answer: (B)

Plants store energy as starch in perennial tissues to fuel metabolism during dormancy and the early return to growth. In grapevines, starch is held in the roots, trunk, and branches, providing a long-term carbohydrate reserve that can be mobilized when photosynthesis is limited and buds begin to break in spring. This stored starch is a ready source of energy and building blocks for new growth as the season starts. Sugar in leaves is used for immediate metabolism and isn’t kept as a long-term dormancy reserve; minerals and moisture aren’t energy stores. So, starch in the roots, trunk, and branches best fits the need to support the vine through dormancy.