Retting of fibres is brought about by the activity of :

Options

A. viruses
B. fungi
C. bacteria
D. mycorrhiza

Answer

**Step-by-Step Solution:**

1. **Understanding Retting**: Retting is a biological process used to separate fibers from the stems of plants. This process involves the breakdown of pectin, a polysaccharide that binds the fibers to the plant material.

2. **Identifying the Microorganisms Involved**: The question asks about the type of organism responsible for the retting process. The options provided are viruses, fungi, bacteria, and mycorrhiza.

3. **Role of Microorganisms in Retting**: Among the given options, bacteria are known to be the primary agents in the retting process. They help in breaking down pectin through their enzymatic activity.

4. **Specific Bacteria Involved**: One of the most notable bacteria involved in the retting of fibers, particularly jute, is Clostridium. This bacterium produces an enzyme called pectinase, which hydrolyzes pectin and facilitates the separation of fibers from the plant stems.

5. **Conclusion**: Based on the information gathered, the correct answer to the question is that retting of fibers is brought about by the activity of bacteria.

**Final Answer**: Bacteria

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