QUANTITATIVE GENETICS

Help please, will donate!

Two doubled-haploid (homozygous) lines of canola differ in leaf length.  In one, the average leaf length is 30 cm, and in the other it is 15 cm.  In both lines, the variance in leaf length is 2 cm2 when grown in similar environments.  In the F2 generation of a cross between these lines, the average leaf length is 22.5 cm, with a variance of 5 cm2.  (Hint: DO NOT ASSUME THAT THE ENVIRONMENTAL VARIANCE =0)


a.   What is the genotypic variance and broad-sense heritability for this trait ?

b.   What is the minimum number of genes required to account for these data