The effective biocontrol agents of serveral plant pathogens are species of

Options

A. Aspergillus
B. Baculoviruses
C. Trichoderma
D. Dragonflies

Answer

**Step-by-Step Solution:**

1. **Understanding Biocontrol Agents**:
- Biocontrol agents are organisms used to control plant diseases and pests through biological methods rather than chemical pesticides. This includes the use of microorganisms to combat plant pathogens.

2. **Identifying the Options**:
- The options provided are:
a. Aspergillus
b. Baculoviruses
c. Trichoderma
d. Dragonflies

3. **Analyzing Each Option**:
- **Aspergillus**: This is a genus of fungi, but it is not primarily known for its role as a biocontrol agent against plant pathogens.
- **Baculoviruses**: These are viruses that primarily target insects, not plant pathogens.
- **Trichoderma**: This is a genus of fungi that is well-documented as an effective biocontrol agent against various fungal diseases in plants. It operates through mechanisms such as antibiosis and parasitism.
- **Dragonflies**: While they are beneficial insects, they are not microorganisms and are not recognized as biocontrol agents for plant pathogens.

4. **Conclusion**:
- Based on the analysis, Trichoderma is the most effective biocontrol agent among the options provided. It is specifically used to combat fungal diseases in plants and is recognized for its potency in biocontrol.

5. **Final Answer**:
- The effective biocontrol agents of several plant pathogens are species of **Trichoderma**.

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