Agrobacterium tumefaciens causes

Options

A. Wilt
B. Damping off
C. Rust
D. Crown gall.

Answer

**Step-by-Step Solution:**

1. **Identify the Organism**: The question asks about Agrobacterium tumefaciens, which is a type of bacteria.

2. **Analyze the Options**: The options given are:
- a) Wilt
- b) Damping off
- c) Rust
- d) Crown gall

3. **Evaluate Each Option**:
- **Option a: Wilt** - This disease can be caused by various pathogens including fungi, viruses, and sometimes bacteria. Therefore, it is not specific to Agrobacterium tumefaciens.
- **Option b: Damping off** - This disease primarily affects seedlings and is caused by fungi. Hence, it cannot be the correct answer.
- **Option c: Rust** - Rust diseases are also caused by fungi and do not relate to Agrobacterium tumefaciens. Thus, this option is incorrect.
- **Option d: Crown gall** - This disease is characterized by the formation of tumors on plants and is specifically caused by Agrobacterium tumefaciens. This makes it the correct answer.

4. **Conclusion**: Based on the analysis, the disease caused by Agrobacterium tumefaciens is **Crown gall**.

**Final Answer**: Crown gall

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