Premium
Comparison of S1 and Modified Ear‐to‐Row Recurrent Selection in Four Maize Populations. I. Effects on Population Means and Variances 1
Author(s) -
Sullivan J. A.,
Kannenberg L. W.
Publication year - 1987
Publication title -
crop science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.76
H-Index - 147
eISSN - 1435-0653
pISSN - 0011-183X
DOI - 10.2135/cropsci1987.0011183x002700060015x
Subject(s) - selection (genetic algorithm) , biology , germplasm , population , hybrid , trait , grain yield , agronomy , index selection , genetic gain , yield (engineering) , statistics , genetic variation , zoology , microbiology and biotechnology , mathematics , genetics , demography , materials science , artificial intelligence , sociology , computer science , gene , metallurgy , programming language
Concern for the narrow genetic base of modern maize ( Zea mays L.) hybrids has resulted in an increased interest in a population approach to germplasm improvement and the most effective recurrent selection methods for the adaptation and improvement of such populations. Two widely used procedures for intrapopulation improvement in maize are S 1 (S) and modified ear‐to‐row (ME) selection. The objective of this study was to compare the effectiveness of these two procedures in four open‐pollinated maize populations, Afton ( A ), Schindelmeiser ( S ), Gelber Badischer Landmais ( G ), and Northwestern Dent ( N ). The primary trait of selection was performance index (PI = grain yield/percent grain moisture). The effects of selection were assessed for PI, the components of PI: grain yield and percent ear moisture at harvest, and other agronomic traits. Genetic variance was estimated to determine possible relationship to observed progress from selection. Data are reported for the initial three cycles of each selection procedure. The S selection for PI resulted in significant average linear increases in PI of 13, 12, and 19% per cycle in A , G , and N , respectively. Increases in PI were a result of increases in grain yield and decreases in percent moisture at harvest. ME selection produced no significant changes in PI. Genetic variances were estimated by subtracting environmental variance (as estimated from single‐cross hybrids) from the phenotypic variance of each cycle. Significant reductions in genetic variances from Cycle 0 were detected for grain yield in (S)Cycle 3 of S , G , and N , and were numerically lower in all selected populations. Genetic variances for percent ear moisture declined significantly in only two instances, ^(ME)Cycle 3 and G(S)Cycle 3. This study indicated that S selection was the preferred method of intrapopulation improvement compared to ME selection.