Location: Vegetable Crops Research Unit
Title: Reflections from 20 years of onion breeding and genetics: Where do we go next? Author
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: April 1, 2012
Publication Date: May 22, 2012
Citation: Havey, M.J. 2012. Reflections from 20 years of onion breeding and genetics: Where do we go next [abstract]. 6th International Symposium on Edible Alliaceae. Paper No. I-04. Technical Abstract: Genetic studies of onion are challenging due to the biennial generation time and relatively high costs of producing segregating families. Before 1990, the genetic bases of numerous morphological traits and disease resistances had been determined, however only one genetic linkage was reported between yellow seedlings and glossy foliage. Over the last 20+ years, the genetic bases of numerous qualitative and quantitative traits have been elucidated. Although identification and mapping of many types of molecular markers has been accomplished, the numbers of genetic markers remained too few, or too expensive, to be widely used as indirect selection tools. Next-generation sequencing technologies represent a paradigm shift for onion genetics because we can now identify large numbers of molecular markers among essentially all populations. As a result, identification of beneficial linkages among genetic markers and important phenotypes makes indirect selection technologies feasible. Robust co-dominant genetic markers, such as microsatellites and single nucleotide polymorphisms, and DNAs from segregating families should be publically available to allow researchers world-wide to assign important phenotypes to specific chromosome segments (BINs). Eventually, reduced representation sequencing of individual onion plants will become common and allow for direct association of DNA polymorphisms with important phenotypes.