Estimation of genetic parameters in two maize recurrent selection programs

Abstract

Recurrent selection is a cyclical breeding procedure that focuses on improving the mean performance of a population by increasing the frequency of favorable alleles, while maintaining adequate genetic variability for continued selection. Iowa Stiff Stalk Synthetic (BSSS) is a maize population that has undergone continuous recurrent selection for more than 50 years as the base population for two independent selection programs (intraand inter-population). This study was designed to estimate the mean performance and important genetic parameters in BSSS after: seven cycles of half-sib (HS) progeny selection [BSSSCO vs BS13(S)C0], six cycles of S2-progeny selection [BS13(S)C0 vs BS13(S)C6], and 11 cycles of reciprocal recurrent selection (RRS) [BSSSCO vs BSSS(R)C11]. A Design II (cross-classified) mating design was constructed to give direct estimates of additive and dominance variance in the individual populations. Fourteen sets of 4 male by 4 female matings for each of the four populations were evaluated in a randomized incomplete block (Reps/Sets) experiment grown in six environments.