In crucifers whiptail disease is caused due to the deficiency of

Options

A. manganese
B. Magnesium
C. molybdenum
D. iron

Answer

To solve the question regarding the cause of whiptail disease in crucifers, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Disease**: The question specifies "whiptail disease" in crucifers. We need to understand what this disease is and its symptoms.

2. **Understand the Nutrient Deficiencies**: The options provided are manganese, magnesium, molybdenum, and iron. We need to analyze how deficiencies of these nutrients affect plants.

3. **Research Whiptail Disease**: Whiptail disease is known to primarily affect the leaves of crucifers. It is characterized by the loss of the upper half of the leaf lamina, leading to a whiptail appearance.

4. **Link the Disease to Nutrient Deficiency**:
- **Manganese**: Deficiency leads to shorter plants but does not cause whiptail disease.
- **Magnesium**: Deficiency causes intervenal chlorosis but is not linked to whiptail disease.
- **Molybdenum**: Deficiency is specifically known to cause whiptail disease in crucifers.
- **Iron**: Deficiency results in yellowing of plants but does not cause whiptail disease.

5. **Conclusion**: Based on the analysis, the nutrient deficiency that causes whiptail disease in crucifers is molybdenum.

### Final Answer:
The deficiency of **molybdenum** causes whiptail disease in crucifers.

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