A straight fertilizer is the one, which is

Options

A. Absorbed by roots directly
B. Absorbed by the plants from aerial spray
C. Having only one primary nutrient
D. Not easily leached

Answer

**Step-by-Step Solution:**

1. **Understanding Straight Fertilizers**: A straight fertilizer is defined as a type of fertilizer that provides only one primary nutrient to the plants. This means that it does not contain a mix of nutrients but focuses solely on one.

2. **Identifying Nutrients**: The primary nutrients that are typically focused on in fertilizers are nitrogen (N), phosphorus (P), and potassium (K). A straight fertilizer will contain only one of these nutrients at a time.

3. **Analyzing the Options**:
- **Option 1**: "Absorbed by root directly" - This is not specific to straight fertilizers as all fertilizers are absorbed by plant roots.
- **Option 2**: "Absorbed by the plant from aerial spray" - Similar to Option 1, this does not pertain specifically to straight fertilizers.
- **Option 3**: "Having only one primary nutrient" - This is the defining characteristic of straight fertilizers.
- **Option 4**: "Not easily leached" - This statement does not accurately describe straight fertilizers as leaching can occur with any fertilizer depending on the conditions.

4. **Conclusion**: Based on the analysis of the options, the correct definition of a straight fertilizer is that it "has only one primary nutrient."

**Final Answer**: A straight fertilizer is one that has only one primary nutrient.

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