Question

The yield of inbred A is 40 q/ha, inbred B is 20 q/ha, check hybrid yield is 45 q/ha and the yield of hybrid (A × B) is 50 q/ha. The standard heterosis (%) is:

• A. 25%
• B. 11.1%
• C. 66.6%
• D. 50%

Hint:

Heterosis calculations:
- Standard heterosis: (F1 - Check hybrid) Check hybrid × 100.
- Better parent heterosis: (F1 - Better parent) Better parent × 100.
- Mid-parent heterosis: (F1 - Mid-parent) Mid-parent × 100.

Answer 1

The Correct Option is B

Step 1: Understanding the Question:
This question tests knowledge of heterosis (hybrid vigour) calculation.

Step 2: Key Formula or Approach:
Standard heterosis (%) = [(F1 yield - Check hybrid yield) Check hybrid yield] × 100.

Step 3: Detailed Explanation:
Given:
- F1 yield = 50 q/ha.
- Check hybrid yield = 45 q/ha.
Standard heterosis = \(\frac{50 - 45}{45} \times 100 = \frac{5}{45} \times 100 = 11.1\%\).
Other options:
- 25% (A): Not correct.
- 66.6% (C): Not correct.
- 50% (D): Not correct.
Thus, the standard heterosis is 11.1%.

Step 4: Final Answer:
Thus, the standard heterosis is 11.1%, which corresponds to option (B).
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