Which of the following cannot be obtained on basal medium?

Options

A. Plantlets from mature embryo
B. Seeding from seed
C. Plantlets from cellus
D. Cellus from explant

Answer

To solve the question "Which of the following cannot be obtained on basal medium?" we will analyze each option provided and determine whether it can be obtained from a basal medium.

### Step-by-Step Solution:

1. **Understand Basal Medium**: Basal medium is a nutrient-rich solution that contains amino acids, sugars (like glucose), and vitamins. It is used to promote the growth of various plant tissues and microorganisms.

2. **Evaluate Each Option**:
- **Option 1: Plantlets from mature embryo**:
- A mature embryo can be cultured on basal medium, and it can develop into a plantlet. Therefore, this option **can be obtained** from basal medium.

- **Option 2: Seedlings from the seed**:
- Seeds can germinate and develop into seedlings when placed in a suitable basal medium. Thus, this option **can be obtained** from basal medium.

- **Option 3: Plantlet from the callus**:
- Callus is a mass of undifferentiated cells that can be induced from plant tissues. However, plantlets are typically derived from callus through further differentiation, which often requires additional growth regulators or specific conditions beyond just a basal medium. Therefore, this option **cannot be obtained** solely from basal medium.

- **Option 4: Callus from X plant**:
- Callus can be generated from explants (tissues) of a plant when cultured on a basal medium. Hence, this option **can be obtained** from basal medium.

3. **Conclusion**: Based on the evaluations, the option that **cannot be obtained** on basal medium is **"Plantlet from the callus."**

### Final Answer:
**Plantlet from the callus cannot be obtained on basal medium.**

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