Evaluation of Populations for Their Potential to Improve Three Maize Hybrids

Abstract

Identification of sources of favorable alleles to improve existing hybrids is one of the most important problems facing a maize (Zea mays L.) breeder. Previous work has demonstrated the effectiveness of a procedure developed by Dudley for identifying populations containing favorable alleles not present in an elite hybrid. However, previously reported work involved at most two elite hybrids. The objective of this study was to evaluate the potential of 20 improved populations to improve the three hybrids made from three inbreds in commercial use. Each of the populations was crossed to LH195, LH212, and LH216. The population × inbred crosses, the three hybrids among the inbreds, and the three inbreds were evaluated in seven U.S. midwestern environments in 1993 and four in 1994. Traits measured were grain yield, grain moisture, plant height, ear height, and concentration of protein, oil, and starch in the grain. For grain yield, 15 of the 20 populations had significant estimates of dominant favorable alleles not present in the highest yielding target hybrid (LH195 × LH212). None of the populations showed potential for reducing ear height. However, seven populations had more favorable recessive alleles than unfavorable dominants for plant height when LH195 × LH212 was the target hybrid. None of the populations tested appeared to have potential for increasing starch concentration in any of the target hybrids. Eight populations showed potential for increasing protein concentration in all three target hybrids. Assumptions required to identify parents were not met for grain moisture, oil concentration, and stalk and root lodging. Disciplines

Detection of quantitative trait loci for heading date based on the doubled haploid progeny of two elite Chinese wheat cultivars

“…So far, no information is available on the role of epistasis in controlling heading date in wheat. Genotypeby-environment interaction has been accepted as another important component of cultivar performance and has received considerable attention in crop breeding programs (Dudley et al 1996).…”

Molecular genetic analysis of flour color using a doubled haploid population in bread wheat (Triticum aestivum L.)

“…Genotype-by-environment interactions have received much attention in crop-breeding programs (Dudley et al 1996), which are important for MAS in crop improvement (Wang et al 1999). A mixedmodel-based composite interval mapping (Wang et al 1999) methodology was proposed for mapping QTLs with additive effects and epistatic effects as well as their QE interactions, and the software QTLNetwork 2.0 (Yang and Zhu 2005) has been developed for analyzing the experimental data.…”

Identification of Tropical and Temperate Maize Populations Having Favorable Alleles for Disease Resistance

“…This theory for assessing the value of populations as donors of favorable alleles has been shown to give results in agreement with known proportions of favorable alleles (Hogan and Dudley, 1991; Pfarr and Lamkey, 1992a; 1992b; Fabrizius and Openshaw, 1994; Stojšin and Kannenberg, 1995). In addition, the method has been used to identify populations having favorable alleles for a number of traits (Dudley et al, 1996; Dudley, 1988b; Pfarr and Lamkey, 1992a; 1992b; Cartea et al, 1996). These results suggest Dudley's method has been effective for identifying populations carrying favorable alleles for several quantitative traits.…”