Variation is appearing during tissue culture are called_______________.

Answer

**Step-by-Step Solution:**

1. **Understanding Tissue Culture**: Tissue culture is a technique where any part of a plant, referred to as the explant, is grown in a controlled environment (in vitro) under sterile conditions using a nutrient medium.

2. **Definition of Explant**: An explant can be any part of the plant, such as leaves, stems, or roots, that is taken out and placed in a test tube or culture vessel for growth.

3. **Process of Regeneration**: From the explant, a whole plant can be regenerated. This process allows for the rapid production of a large number of plants from a single explant.

4. **Occurrence of Variations**: During the tissue culture process, variations can occur in the regenerated plants. These variations are not due to genetic mutations but arise from the somatic cells being cultured.

5. **Definition of Somaclonal Variation**: The variations that appear during tissue culture are specifically called "Somaclonal Variation." This term refers to the genetic variations observed among the progeny of plants that have been regenerated from somatic cells cultured in vitro.

6. **Conclusion**: Therefore, the answer to the question is that variations appearing during tissue culture are called Somaclonal Variation.

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