Which is not true for abscisic acid?
(a) Acts as an anti-transpirant
(b) Synthesized in chloroplast from carotenoids
(c) Increases stress tolerance in plants
(d) Induces epinasty of leaves and flowers

Options

A. Acts as an anti-tranpirant
B. Synthesized in chloroplast from carotenoids
C. Increases stress tolerance in plants
D. Induces epinasty of leaves and flowers

Answer

To determine which statement about abscisic acid (ABA) is not true, we will evaluate each option provided in the question.

### Step-by-Step Solution:

1. **Understanding Abscisic Acid (ABA)**:
- Abscisic acid is a plant hormone that plays a crucial role in plant stress responses, particularly during drought and salinity conditions. It is known to help in seed dormancy and acts as an antagonist to gibberellins, which promote seed germination.

2. **Evaluate Option (a)**:
- **Acts as an anti-transpirant**:
- This statement is true. ABA helps to reduce water loss by closing stomata, thus acting as an anti-transpirant.

3. **Evaluate Option (b)**:
- **Synthesized in chloroplast from carotenoids**:
- This statement is also true. ABA is synthesized in the chloroplasts from carotenoids, which are pigments found in plants.

4. **Evaluate Option (c)**:
- **Increases stress tolerance in plants**:
- This statement is true as well. ABA is known to enhance the plant's ability to withstand stress conditions such as drought and salinity.

5. **Evaluate Option (d)**:
- **Induces epinasty of leaves and flowers**:
- This statement is not true. Epinasty refers to the downward bending of leaves and flowers, which is typically induced by other hormones like ethylene, not by abscisic acid.

### Conclusion:
Based on the evaluations, the statement that is not true for abscisic acid is:
**(d) Induces epinasty of leaves and flowers.**