Characterization and estimation of genetic parameters in the interpopulations formed by crossing unselected and selected BSSS and BSCB1 maize synthetics

Abstract

A Design II mating design was used to produce half-sib and full-sib progenies in three cross populations: BSSSCO x BSCBICO, BSSS(R)C9 X BSCB1(R)C9, and BS13(S)C3 x BSCB1(R)C9. Progenies were evaluated in a replications-within-sets with two replications at five locations. Data were collected for grain yield, grain moisture, root and stalk lodging, dropped ears, plant and ear height, days to anthesis and silking, and tassel branch number. The objectives were to compare the relative performance among single crosses from selected and unselected cross populations and to estimate genetic parameters in the hybrid populations. Reciprocal recurrent selection (RRS) resulted in a significant increase in grain yield for the cross population. RRS was more effective than the combined progress of the halfsib (HT) and self (S) methods to increase yield in the population cross and to reduce root and stalk lodging, ear height, days to anthesis and silking, and tassel branches. The additive variance component was the most important component of genetic variability for all traits. For grain yield, the additive variance components increased with selection; however, the original population cross showed greater additive by environment interaction variance than the improved populations. RRS for grain yield resulted in an