The pre-requistie for effective exploitation of natural genes available in the populations is:

Options

A. Collection and preservation of germplasm
B. Cross hybridization of selected parents
C. Testing the superior cultivars in farmers field
D. Commericialisation of crop varieties

Answer

**Step-by-Step Solution:**

1. **Understanding Plant Breeding**: Plant breeding is a scientific approach that involves changing the genetic composition of crop plants to enhance their qualities for human use. This process is essential for improving crop varieties.

2. **Identifying the Purpose**: The main goal of plant breeding is to produce crop varieties that meet human needs better than existing varieties. This can include traits such as higher yield, disease resistance, or better nutritional value.

3. **Recognizing the Steps in Plant Breeding**: The process of plant breeding involves several key steps, which include:
- Collection of variability
- Selection of parents
- Hybridization
- Testing and evaluation of new varieties
- Commercialization of successful varieties

4. **Focusing on the Prerequisite**: The first and most crucial step in the plant breeding process is the collection and preservation of germplasm. Germplasm refers to the genetic material that is collected from various wild varieties, cultivated species, and their relatives.

5. **Importance of Germplasm Collection**: Collecting and preserving germplasm is essential because it provides the genetic diversity needed for selection and breeding. Without a diverse genetic base, it would be challenging to select suitable parents for hybridization.

6. **Conclusion**: Therefore, the prerequisite for effective exploitation of natural genes available in the populations is the "collection and preservation of germplasm."

**Final Answer**: The pre-requisite for effective exploitation of natural genes available in the populations is the collection and preservation of germplasm.

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