|Brummer, E - UNIV. OF GEORGIA|
Submitted to: Plant and Animal Genome Conference
Publication Type: Abstract Only
Publication Acceptance Date: November 19, 2007
Publication Date: N/A
Technical Abstract: Genetic improvement of forage, turf, and biofuel crops requires rapid, inexpensive, and repeatable measurement of plant phenotypes. For many important traits, such as biomass yield, abiotic stress tolerances, resistance to some disease pathogens, and long-term persistence, inability to accurately measure plant phenotypes represents a huge impediment to breeding progress. Marker-assisted selection (MAS) has been proposed as a mechanism to improve the efficiency of selection, particularly for such low-heritability traits. Implementation of MAS would incorporate use of DNA markers associated with plant phenotypes combined with measurement of some plant phenotypes. We propose the use of among-and-within-family (AWF) selection as a framework model for optimizing MAS in a long-term recurrent selection program. The AWF framework can be used to facilitate replication among and within locations for a set of families, increasing heritability of traits measured on a family-mean basis. Each family is represented by a fixed number of plants upon which phenotype is measured and markers are scored. Use of association mapping techniques will identify markers associated with plant phenotypes. Using phenotype-marker associations as a calibration, additional plants of the best families can be established in greenhouse facilities and form the basis of more intensive within-family selection for markers. While this strategy could be implemented with any marker system, it would be optimized with single-nucleotide polymorphism (SNP) markers located within functional genes, potentially reducing the needs for future phenotyping efforts.