ABSTRACT
The use of marker-assisted selection in developing improved varieties of soybean Y.-C. Lee, R. Lemes Hamawaki, V. Colantonio, M. J. Iqbal and D. A. Lightfoot, Southern Illinois University, USA
1 Introduction
2 Genomes as intellectual property
3 Methods for MAS
4 Marker development
5 Choice of markers
6 Identification of polymorphism
7 Genetic and association map development
8 Marker-assisted recovery of recurrent parent genome
9 MAS in recurrent cross populations
10 Scoring of phenotypes
11 Use of molecular markers to select desirable traits in soybean
12 Future trends and conclusion
13 Where to look for further information
14 References
Soybean geneticists and breeders aim to improve harvestable yield, reduce crop losses and reduce crop inputs by re-assortment among favourable haplotypes (Iqbal and Lightfoot 2004; Stefaniak et al. 2005; Lightfoot 2008, 2015) and the incorporation of new genes for new traits (Anand 1983; Arelli et al. 1994; Prabhu et al. 1999; Luckew et al. 2013). Rapid genetic gains can be made by incorporating genes for resistance to biotic and abiotic stresses. The positive effect of stress resistance is so reliable that journals rarely accept yield data for publication (Hnetkovsky 1994; Hnetkovsky et al. 1996). However, each stressor has an economic threshold, a point at which significant yield loss occurs (Gibson 1994), which is often contentious. For each stress it is important to determine the threshold and use resistance loci only when the threshold is exceeded. The reason for this
is the yield reduction caused by the incorporation of resistance genes in cases of absence of disease or other stressors.
