A simple test for detection of linkage.

The paper presents a proposition for detection of linkage of genes responsible for metrical traits. Taking into account the expected means for early generations (F(1), F(2), F(3)) and a population of homozygous lines (in this case doubled haploid lines, DH derived from a cross between two homozygous parents) as well as estimators of genetic parameters m, [d], [i], [h] and [l], the expected values for these parameters in the presence of linkage have been formulated. It was found that when there is no linkage, the expression F(1) - 6F(2) + 8F(3) - 3DH(mean) is equal to zero. Thus, an experiment covering DH lines and F(1), F(2), F(3) hybrids makes it possible to obtain, beside information of interest, also information on presence or absence of linkage.