Answer:
h² = 0.6
Step-by-step explanation:
Before answering the question, we need to know a few concepts.
Artificial selection is the selecting practice of a specific group of organisms in a population -that carry the traits of interest- to be the parents of the following generations.
Parental individuals carrying phenotypic values of interest are selected from the whole population. These parents interbreed, and a new generation is produced.
The selection differential, SD, is the difference between the mean value of the trait in the population (X₀) and the mean value of the parents, (Xs). So,
SD = X₀ - Xs
Heritability in the strict sense, h², is the genetic component measure to which additive genetic variance contributes. The heritability might be used to determine how the population will respond to the selection done, R.
h² = R/SD
The response to selection (R) refers to the metric value gained from the cross between the selected parents. R can be calculated by multiplying the heritability h², with the selection differential, SD.
R = h²SD
R also equals the difference between the new generation phenotypic value (X₁) and the original population phenotypic value (X₀),
R = X₀ - X₁
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Now that we know these concepts and how to calculate them, we can solve the proposed problem.
Available data:
- You are selecting rice´s decreased period of maturation.
- The population of rice has a mean maturation time of 30 days → X₀
- Parental selected average period to maturation is 25 days → Xs
- F1 plants mature on average in 27 days → X₁
- N arrow sense Heritability → h²
According to what we sow previously, we need to find out the value of h².
We know that h² = R/SD, so we need to get R and SD first.
R = X₁ - X₀
R = 27 - 30
R = -3
SD = Xs - X₀
SD = 25 - 30
SD = -5
Knowing this, we can calculate h²
h² = R/SD
h² = -3/-5
h² = 0.6