Choose the wrong pair

Options

A. Root knot of vegetables-Meloidogyne species
B. Late blight of Potato-Alternaria solani
C. Black rust of Wheat-Puccinia graminis
D. Loose smut of Wheat-Ustilago nuda.

Answer

To solve the question "Choose the wrong pair," we need to evaluate the given options regarding plant diseases and their causal organisms. Here’s a step-by-step breakdown of the solution:

### Step 1: Analyze the First Option
- **Option**: Root knot of vegetables - Causal Organism: Melidogynes species
- **Evaluation**: This option is correct. Root knot is indeed caused by the nematode Melidogynes species.

### Step 2: Analyze the Second Option
- **Option**: Late blight of potato - Causal Organism: Alternaria solani
- **Evaluation**: This option is incorrect. Late blight of potato is caused by Phytophthora infestans, not Alternaria solani. Alternaria solani causes early blight, not late blight.

### Step 3: Analyze the Third Option
- **Option**: Black rust of wheat - Causal Organism: Puccinia graminis
- **Evaluation**: This option is correct. Black rust of wheat is caused by the fungus Puccinia graminis.

### Step 4: Analyze the Fourth Option
- **Option**: Loose smut of wheat - Causal Organism: Ustilago nuda
- **Evaluation**: This option is also correct. Loose smut of wheat is caused by the fungus Ustilago nuda.

### Conclusion
After evaluating all the options, the only incorrect pair is:
- **B**: Late blight of potato is incorrectly paired with Alternaria solani.

### Final Answer
The wrong pair is **B: Late blight of potato - Alternaria solani**.

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