Which of the following is not used as a biopesticide ?

Options

A. Trichoderma harzianum
B. Nucleopolyhedrovirus
C. Xanthomonas campestris
D. Bacillus thuringiensis

Explanation

To determine which of the following options is not used as a biopesticide, we will analyze each option provided in the question:

1. **Trichoderma**:
- Trichoderma is a genus of fungi that acts as a biocontrol agent. It is commonly used to control other fungal pathogens in plants. Therefore, Trichoderma is considered a biopesticide.

2. **Nucleopolyhedrovirus**:
- This is a virus that belongs to the family Baculoviridae. Nucleopolyhedroviruses are known to infect and kill various insect pests and arthropods. They are used as biopesticides to control insect populations. Thus, Nucleopolyhedrovirus is also a biopesticide.

3. **Xanthomonas campestris**:
- Xanthomonas campestris is a bacterium that causes diseases in plants, such as black rot in crucifers. It does not act as a biocontrol agent or biopesticide; instead, it is a pathogen. Therefore, Xanthomonas campestris is not used as a biopesticide.

4. **Bacillus thuringiensis**:
- Bacillus thuringiensis (Bt) is a bacterium that produces toxins harmful to certain insect larvae. It is widely used as a biopesticide in agriculture to control pest populations. Hence, Bacillus thuringiensis is a biopesticide.

After analyzing all the options, we conclude that the correct answer is:

**Xanthomonas campestris** is not used as a biopesticide.