A widely but periodically occurring plant disease is

Options

A. Endemic
B. Epidemic
C. Sporadic
D. Epiphytotic

Answer

To solve the question "A widely but periodically occurring plant disease is", we need to analyze the options provided and understand the definitions of each term related to plant diseases.

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for a type of plant disease that occurs widely and periodically.

2. **Analyzing the Options**:
- **Option 1: Endemic**: Endemic diseases occur at relatively constant levels in the same area each year. They are periodic but not widely distributed. Therefore, this option does not fit the criteria of being widely occurring.
- **Option 2: Epidemic**: Epidemic diseases are widespread but do not occur periodically. They can spread rapidly but are not defined by a periodic occurrence. Thus, this option is also incorrect.
- **Option 3: Sporadic**: Sporadic diseases occur at irregular intervals and are limited to specific areas. They do not fit the criteria of being widely occurring or periodic. Hence, this option is incorrect as well.
- **Option 4: Epiphytotic**: Epiphytotic diseases are defined as those that occur periodically and involve a major area of crops. This matches the criteria of being widely and periodically occurring.

3. **Conclusion**: Based on the analysis of the definitions, the correct answer is **Option 4: Epiphytotic**.

### Final Answer:
A widely but periodically occurring plant disease is **epiphytotic**.

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