Mouse ear' in pecan is due to the deficiency of

Options

A. Ca
B. Ni
C. Cu
D. Mn

Answer

**Step-by-Step Solution:**

1. **Understanding the Problem**: The question asks about the cause of the 'mouse ear' condition in pecan trees, specifically what mineral deficiency leads to this abnormality.

2. **Identifying the Condition**: 'Mouse ear' is a growth abnormality observed in pecan trees. It is characterized by the leaves appearing small and curled, resembling a mouse's ear.

3. **Historical Context**: Initially, 'mouse ear' was thought to be caused by spring cold injury before bud break. This means that the condition was first attributed to environmental factors rather than nutritional deficiencies.

4. **Further Investigation**: Over time, researchers considered other potential causes for the 'mouse ear' condition. It was later thought to be associated with a viral pathogen.

5. **Linking to Mineral Deficiency**: Despite the initial thoughts about cold injury and viral pathogens, it was ultimately determined that the 'mouse ear' condition is primarily due to a deficiency in a specific mineral.

6. **Identifying the Mineral**: Among the options provided (calcium, nickel, copper, manganese), the correct answer is nickel (Ni). Nickel deficiency is known to cause the 'mouse ear' condition in pecan trees.

7. **Conclusion**: Therefore, the deficiency responsible for the 'mouse ear' condition in pecan trees is due to a lack of nickel.

**Final Answer**: The 'mouse ear' in pecan is due to the deficiency of nickel (Ni).

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