Estimation of Second Degree Genetic Parameters from a Set of Half-Diallel Crosses

The estimation of second degree genetic parameters from a set of half-dialll crosses has been erroneously done by several workers by using the formulae which are appropriate only for a full-diallel set of crosses. While the components of genetic parameters remain the same as for the full-diallel set, those for the error differ. Appropriate formulae to give the correct coefficients of the error term have been provided. The two cases of homozygous and of heterozygous parents have been covered.