Bolting is -

Options

A. Internodal elongation just prior to flowering in beet, cabbage and many plants with rosette habit.
B. A type of grafting
C. Nodal elongation in certain plants
D. None

Answer

**Step-by-Step Solution:**

1. **Understanding Bolting**: Bolting refers to the rapid elongation of the flowering stem in certain plants. This phenomenon typically occurs just before the plant flowers.

2. **Identifying Plants that Bolt**: Common examples of plants that exhibit bolting include beet, cabbage, and other plants that have a rosette growth habit. These plants tend to grow close to the ground and then suddenly elongate their stems as they prepare to flower.

3. **Role of Plant Hormones**: The primary plant hormone responsible for inducing bolting is Gibberellic Acid (GA), which is a type of gibberellin. Gibberellins are known to promote various physiological responses in plants, including stem elongation and flowering.

4. **Chemical Nature of Gibberellic Acid**: Gibberellic Acid is acidic in nature and is derived from terpenes, which are organic compounds produced by a variety of plants. This hormone is classified as a plant growth regulator or phytohormone.

5. **Application in Agriculture**: In agricultural practices, gibberellic acid can be applied to crops like sugarcane to enhance inter-nodal elongation, which can lead to increased productivity by allowing the plant to store more sugar.

6. **Conclusion**: Based on the above points, bolting is defined as inter-nodal elongation just prior to flowering in certain plants, particularly those with a rosette habitat, making option 1 the correct answer.

**Final Answer**: Bolting is inter-nodal elongation just prior to flowering in beet, cabbage, and many plants with rosette habitat.

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