Trichoderma harizianum has proved to be a useful microorganism for

Options

A. gene transfer in higher plants
B. biological control of soil-borne plant pathogens
C. bioremediation of contaminated soils
D. reclamation of wastelands.

Answer

**Step-by-Step Solution:**

1. **Identify the Organism**: The question asks about the usefulness of the microorganism Trichoderma harzianum.

2. **Evaluate the Options**: The question provides four options regarding the usefulness of Trichoderma harzianum. We need to analyze each option to determine which one is correct.

3. **Option Analysis**:
- **Option 1: Gene transfer in higher plants**: This option is incorrect. Trichoderma species do not have a role in gene transfer in higher plants.
- **Option 2: Biological control of soil-borne plant pathogens**: This option is correct. Trichoderma harzianum is known as a potent biological agent that protects plants from various fungal diseases caused by pathogens such as Fusarium, Phytophthora, and Sclerotinia. It helps control soil-borne diseases effectively.
- **Option 3: Bioremediation of contaminated soil**: This option is incorrect. Trichoderma harzianum does not play a significant role in bioremediation processes.
- **Option 4: Reclamation of wasteland**: This option is also incorrect. Trichoderma harzianum is not typically associated with wasteland reclamation.

4. **Conclusion**: Based on the analysis, the correct answer is that Trichoderma harzianum has proved to be a useful microorganism for the biological control of soil-borne plant pathogens.

**Final Answer**: Trichoderma harzianum has proved to be a useful microorganism for the biological control of soil-borne plant pathogens.

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