Name the abiotic factor which is not essential for early growth of the plant but growth cannot be sustained in its absence?

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for an abiotic factor that is not essential for the early growth of a plant but is necessary for sustaining growth later on.

2. **Defining Abiotic Factors**: Abiotic factors are non-living components of the environment that affect living organisms. These include elements like light, temperature, water, soil, and nutrients.

3. **Identifying Early Growth Needs**: During the early growth stages, particularly seed germination, plants primarily require water and nutrients from the soil. Light is not a critical factor at this stage.

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