Question

    In a breeding experiment involving quantitative traits,

    a breeder calculated the phenotypic variance (VP) as 40 and genotypic variance (VG) as 30. Based on these values, what is the correct estimate of broad-sense heritability and what does it imply about trait inheritance?
    A 50%; low environmental effect Correct Answer Incorrect Answer
    B 75%; high genetic control Correct Answer Incorrect Answer
    C 25%; strong environmental influence Correct Answer Incorrect Answer
    D 100%; no environmental variance Correct Answer Incorrect Answer
    E 60%; moderate genetic control Correct Answer Incorrect Answer

    Solution

    Broad-sense heritability (H²) is calculated as: H² = VG / VP = 30 / 40 = 0.75 or 75%. This indicates that 75% of the phenotypic variance is due to genetic factors, implying high genetic control and suggesting that the trait is largely heritable, making selection more effective.  

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