The disease 'little leaf' of fruit trees is caused by the deficiency of

Options

A. Copper
B. Zinc
C. Manganese
D. Cobalt

Answer

**Step-by-Step Solution:**

1. **Understanding the Disease**: The question refers to the disease 'little leaf' which affects fruit trees. To answer the question, we first need to understand what 'little leaf' disease is.

2. **Identifying Symptoms**: The symptoms of 'little leaf' disease include:
- Interveinal chlorosis (yellowing between the veins of the leaves)
- Distortion of leaves
- Failure of leaves to expand properly, leading to smaller leaf size
- Overall stunted growth of the plant

3. **Connecting Symptoms to Nutrient Deficiency**: After identifying the symptoms, we need to determine which nutrient deficiency is responsible for these symptoms. The options provided are copper, zinc, manganese, and cobalt.

4. **Researching Nutrient Roles**: Among the listed nutrients:
- **Copper**: Involved in photosynthesis and enzyme activation.
- **Zinc**: Essential for leaf development and enzyme function; deficiency leads to stunted growth and leaf distortion.
- **Manganese**: Important for photosynthesis and enzyme activation but does not typically cause 'little leaf' symptoms.
- **Cobalt**: Primarily associated with nitrogen fixation in legumes.

5. **Conclusion**: Based on the symptoms and the role of the nutrients, the deficiency that causes 'little leaf' disease is specifically linked to zinc. Therefore, the correct answer to the question is that the disease 'little leaf' of fruit trees is caused by the deficiency of zinc.

**Final Answer**: The disease 'little leaf' of fruit trees is caused by the deficiency of **Zinc**.

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