Silencing of mRNA has been used in producing transgenic plants resistant to:

Options

A. bollworms
B. nematodes
C. white rusts
D. bacterial blights

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the application of mRNA silencing in producing transgenic plants that are resistant to a specific threat.

2. **Identifying mRNA Silencing**: mRNA silencing, also known as RNA interference (RNAi), is a technique used to silence or deactivate specific genes in an organism. This process is a natural defense mechanism found in eukaryotic cells.

3. **Function of RNA Interference**: The RNA interference mechanism works by creating double-stranded RNA (dsRNA) that binds to the target mRNA, preventing its translation into proteins. This effectively silences the gene associated with the target mRNA.

4. **Application in Transgenic Plants**: This technique has been utilized to develop transgenic plants that are resistant to various pests and diseases. One notable example is the tobacco plant, which has been genetically modified to be resistant to nematodes.

5. **Analyzing the Options**:
- **Option A: Bollworms** - This refers to pests affecting cotton crops. The resistance in cotton is achieved through different methods, such as the introduction of Bt toxin, not mRNA silencing.
- **Option B: Nematodes** - This is correct. The tobacco plant has been made resistant to nematodes using mRNA silencing techniques.
- **Option C: White Rust** - This is a disease affecting mustard plants, not a pest that can be targeted by mRNA silencing.
- **Option D: Bacterial Blights** - This is a disease affecting barley, not a target for mRNA silencing.

6. **Conclusion**: Based on the analysis, the correct answer is **Option B: Nematodes**, as silencing of mRNA has been effectively used to produce transgenic plants resistant to nematodes.

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