Bt toxin is harmful to insects like-

Options

A. Lepidosterans (tobacco budworm, armyworms)
B. Coleopterons (bettles)
C. Dipterans (files and mosquito)
D. All

Answer

**Step-by-Step Solution:**

1. **Understanding Bt Toxin**: Bt toxin is a biological pesticide derived from the bacterium Bacillus thuringiensis. It produces a protein that is toxic to certain insects.

2. **Mechanism of Action**: The Bt toxin releases a cry protein that disrupts the digestive system of susceptible insects, leading to their death.

3. **Identifying Affected Insects**: The toxin is particularly harmful to specific groups of insects. These include:
- **Lepidopterans**: This group includes moths and butterflies. A common example is the corn borer, which is a significant pest in agriculture.
- **Coleopterans**: This group includes beetles. An example is the Colorado potato beetle, which affects potato crops.
- **Dipterans**: This group includes flies and mosquitoes. For instance, the larvae of certain flies can be affected by Bt toxin.
- **Caterpillars**: These are the larval stages of moths and butterflies, which are also susceptible to Bt toxin.

4. **Conclusion**: Bt toxin is harmful to various insects, including Lepidopterans (like caterpillars and moths), Coleopterans (like beetles), and Dipterans (like mosquitoes and flies).

**Final Answer**: Bt toxin is harmful to insects such as Lepidopterans (caterpillars and moths), Coleopterans (beetles), and Dipterans (flies and mosquitoes).

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