查看文章

Because traits such as grain yield are polygenically inherited and strongly influenced by environment, determination of genotypic values from phenotypic expression is not precise and improvement strategies are frequently based on low heritabilities. Increased knowledge of the genetic factors involved in the expression of yield should enhance the improvement of this trait. The objectives of this study were to identify and locate genetic factors (i.e., quantitative trait loci, QTL's) associated with grain yield and 24 yield‐related traits in two F₂ populations of maize (Zea mays L.) using isozyme marker loci. (The populations were generated by selfing the F₁, hybrids CO159 ✕ Tx303 and T232 ✕ CM37.) In addition, assessments of the types and magnitudes of gene effects expressed by these QTL's were made. About two‐thirds of the associations among 17 to 20 marker loci and the 25 quantitative traits were significant with a …