Quantitative genetics and breeding methods

Plant breeding is an applied science that includes information and techniques from different disciplines, including quantitative genetics, to develop improved cultivars. Quantitative genetics itself will not either directly develop superior cultivars or enhance our germplasm resources. The principles of quantitative genetics, however, are considered at all stages of plant breeding. Parameters have been developed for determining effective population sizes, genetic variability within breeding populations. genetic effects important for inbreeding depression and heterosis, estimation of heritability, and predicting future genetic advance, types of genetic effects among different types of hybrids, and selection methods for germplasm enhancement. Quantitative genetics is one of the tools available to plant breeders that contributed to the genetic gains realized for most of our important crop species during the 20th century.