3 CYCLES OF SELECTION AMONG AND WITHIN HA LF-SIB FAMILIES IN THE EEL(4) MAIZE POPULATION

Three cycles of selection among and within half-sib families were eval uated on the EEL, maize population, in die north, south, and highland regions of Espirito Santa State, Brazil, from 1985 to 1988. Year by ye ar, two hundred families were evaluated using two 10 x 10 lattices, wi th two replications. For the crossover, the selection rates of 15% amo ng progenies, and 12,5% within progenies, were used. For the trait ear weight, the analysis of individual and combined variance detected hig hly significant differences for progenies and for the interaction of p rogenies x locations. The progenies presented, on the average, a good performance, producing at the first, second and third cycles 91.0 g, 1 29.3 g and 153.5 g per plant, respectively. The heritability values, s tricto sensu, varied for locations and cycles, ranging from 12.0% to 4 4.0%. On average, those values reached 28.5%, 12.0% and 26.2%, from th e first to the third cycles, respectively. The magnitudes of the genet ic parameters, specially at the third cycle, express the population va riability that, associated to high means of progenies productivity, in dicate the importance of this population in a breeding program. Mean g enetic gains expected with selection combined per cycle, from first to third cycles, were 6.5%, 3.0% and 4.0%, respectively. Therefore, if s election was practiced per location, this value could reach up to 12.3 %.