Question

Which of the following breaks dormancy of a potato tuber?

• A. Gibberellin
• B. Indole acetic acid
• C. Abscisic acid
• D. Zeatin

Answer 1

The correct option is A Gibberellin

Gibberellins are involved in seed germination in certain plants. In a classic experiment involving barley seed germination, researchers showed that the release of gibberellin from the embryo triggers the synthesis of $\alpha$-amylase, an enzyme that digests starch in the endosperm. As a result, glucose becomes available for absorption by the embryo. Similar response is also seen in case of starch storing potato tubers, where gibberellins promote elongation of plantlets from eyes of potato tuber. Although enzymes mobilize starch reserves in many types of seeds, gibberellin control of seed enzymes appears restricted to cereals and other grasses. In addition to mobilizing food reserves in newly germinated grass seeds, application of gibberellins substitutes for low-temperature or light requirements for germination in seeds of plants such as lettuce, oats and tobacco.

Thus, the correct answer is option A.