Abstract:Computer simulation was used to study the reliability of heritability (h_N~2) anddomihance ratio ((H/D)~(1/2)) estimates obtained by NCⅠ, NCⅡ and DIA designs fromrandom mating populations and inbreeding populations with 8 sample sizesrespectively, and the reliability of h_N~2 and (H/D)~(1/2) estim