Exanthema, a diseas due to Cu -deficiency is characterized by:

Options

A. Loss of pigments
B. Longitudinal break of bark
C. Defoliation
D. Curiling of margin of leaves

Answer

### Step-by-Step Solution:

1. **Identify the Disease**: The question mentions "Exanthema," which is a disease that occurs due to copper deficiency in plants.

2. **Understand the Cause**: Exanthema specifically arises from a lack of copper (Cu) in the plant, which is an essential micronutrient for various physiological processes.

3. **Recognize the Symptoms**: The symptoms of Exanthema include:
- **Yield of Gums on the Bark**: This refers to the secretion of gum-like substances on the bark of the affected trees.
- **Longitudinal Breakage of Bark**: This indicates that the bark of the tree experiences cracking or splitting along its length.

4. **Effect on Fruit Bearing Capacity**: The disease also negatively impacts the fruit-bearing capacity of the tree, which means that the tree may produce fewer or no fruits due to the stress caused by copper deficiency.

5. **Summarize the Characteristics**: Therefore, the key characteristics of Exanthema due to copper deficiency are:
- Yield of gums on the bark
- Longitudinal breakage of bark
- Reduced fruit-bearing capacity

### Final Answer:
Exanthema, a disease due to copper deficiency, is characterized by the yield of gums on the bark, longitudinal breakage of bark, and a decrease in the fruit-bearing capacity of the tree.

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