SIMULATION OF MARKER ASSISTED SELECTION FOR NONADDITIVE TRAITS

Marker Assisted Selection (MAS) based on additive effects associated w ith alleles at marker loci, estimated by linear regression of individu al phenotype on the markers, was applied to characters with non-additi ve gene action and non-additive environment. The base population was t he F-2 generation of a cross between two inbred lines. Computer simula tions of MAS were conducted for characters with dominance, epistasis a nd genotype-environment interaction approximated by the 'additive-mult iplicative' model. MAS was more effective than purely phenotypic selec tion in all cases. The efficiency of MAS for characters with non-addit ive gene action is comparable to (and for negative dominance even high er than) the efficiency of MAS for strictly additive characters. Envir onmental non-additivity, however, lowers the efficiency of MAS. Almost all results concerning the efficiency of MAS in our previous simulati ons of purely additive traits are applicable to non-additive traits.