Comparison among selection methods in maize cv. Centralmex

Abstract

The maize (Zea mays L.) cv. Centralmex was planted in four contiguous blocks. Four mating schemes were used: reciprocal crosses of the upper ears and selfing of the lower ears; reciprocal crosses of the upper ears without selfing; sequential pollination or chain crosses and selfing of the upper ears. Selection schemes were based on full-sib progeny evaluation for blocks 1, 2 and 3 and on S₁ progeny evaluation for block 4. Comparisons were made by taking into account expected progress based on observed and standardized differential of selection estimated as a function of selection intensity; expected progress by making constant the selection intensity with varying effective population size and vice-versa; variation index and coefficient of heritability. In all realized comparisons the results showed superiority of the S₁ progeny evaluation.