Little leaf of brinjal is caused by

Options

A. Alga
B. Fungus
C. Mycoplasma
D. Bacterium.

Answer

### Step-by-Step Solution:

1. **Understanding the Disease**: The question asks about the cause of "little leaf of brinjal." This disease affects the brinjal (eggplant) and is characterized by specific symptoms.

2. **Identifying Symptoms**: The symptoms of little leaf disease include:
- Shortening of petioles (the stalks that attach leaves to the stem).
- Very small leaves that may appear almost absent.
- Leaves that are soft and yellow in color.
- Affected plants do not produce flowers or fruits, especially if the disease occurs in the early growth stages.

3. **Recognizing the Causative Agent**: The causative agent of little leaf disease is identified as a plant pathogen. It is specifically caused by a type of mycoplasma known as phytoplasma.

4. **Understanding Mycoplasma**: Mycoplasmas are a group of bacteria that lack a cell wall. They are different from typical bacteria and are classified under the kingdom Monera. Phytoplasmas are mycoplasma-like organisms that specifically affect plants.

5. **Transmission**: The disease is transmitted by an insect vector, specifically the leafhopper known as Hismoneus Fisitis, which spreads the phytoplasma from infected to healthy plants.

6. **Evaluating Options**: The question provides four options: alga, fungus, mycoplasma, and bacterium.
- Alga and fungus are incorrect as they do not cause this disease.
- Mycoplasma is the correct answer, as it specifically refers to the phytoplasma causing the little leaf disease.
- Bacterium is also incorrect because, while mycoplasmas are prokaryotes like bacteria, they are distinct in their lack of a cell wall.

7. **Conclusion**: The correct answer to the question "Little leaf of brinjal is caused by" is **mycoplasma**.

### Final Answer:
**Mycoplasma (specifically phytoplasma)**

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