|Buckler, Edward - Ed|
Submitted to: The Plant Cell
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/12/2004
Publication Date: 10/15/2004
Citation: Wilson, L.M., Whitt, S.R., Ibanez, A.M., Rocheford, T.R., Goodman, M.M., Buckler Iv, E.S. 2004. Dissection of maize kernel composition and starch production by candidate gene association. The Plant Cell. 16:2719-2733. Interpretive Summary: As a result of increased demands on food production due to escalating population growth and environmental degradation, interest in improved breeding strategies for important agricultural crops is growing. Identifying and understanding the genetic basis of the starch pathway in maize--the largest production crop in the world--is an important step in improving cereal grain production and in maximizing the return on industrial corn processing. In this study, we used an association approach to evaluate six candidate genes involved in kernel starch biosynthesis. This high-resolution approach allowed us to locate regions of DNA that affect starch content and quality in maize. In the future, plant breeders and commercial processors can exploit these genes to alter the type and/or relative amount of starch in maize for agronomic and economic gain.
Technical Abstract: Because maize is a significant source of subsistence agriculture for much of the world's human and domesticated animal population, breeding strategies that improve kernel quality and increase yield will be necessary to meet the demands of a growing population. In this study, six candidate genes involved in starch biosynthesis (Ae1, Bt2, Sh1, Sh2, Su1, and Wx1) were tested for associations with starch concentration and starch composition quality. Although linkage mapping has already identified several regions of the maize genome that influence starch content or quality, using an association approach while controlling for population structure allowed us to locate nucleotide polymorphisms with a substantial increase in resolution. Nucleotide sites in Bt2, Sh1, and Sh2 showed significant associations for kernel composition traits, while Ae1 and Sh2 showed significant associations for starch pasting properties. Ae1 and Sh1 also associated with amylose levels. High-resolution markers for these six starch genes, as well as a host of candidate polymorphisms identified by this study, can be used in future studies to further elucidate this critical plant pathway.