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January, 2009
Source: Crop
Science
Genomic selection for crop
improvement
Elliot L. Heffnera, Mark E. Sorrellsa
Dep. of Plant Breeding and Genetics, Cornell Univ., Bradfield
Hall, Ithaca, NY 14853
and Jean-Luc
Jannink
USDA-ARS, R.W. Holley Center for Agriculture and Health, Cornell
Univ., Ithaca, NY 14853
ABSTRACT
Despite important strides
in marker technologies, the use of marker-assisted selection
has stagnated for the improvement of quantitative traits.
Biparental mating designs for the detection of loci
affecting these traits (quantitative trait loci [QTL])
impede their application, and the statistical methods used
are ill-suited to the traits' polygenic nature. Genomic
selection (GS) has been proposed to address these
deficiencies. Genomic selection predicts the breeding values
of lines in a population by analyzing their phenotypes and
high-density marker scores. A key to the success of GS is
that it incorporates all marker information in the
prediction model, thereby avoiding biased marker effect
estimates and capturing more of the variation due to
small-effect QTL. In simulations, the correlation between
true breeding value and the genomic estimated breeding value
has reached levels of 0.85 even for polygenic low
heritability traits. This level of accuracy is sufficient to
consider selecting for agronomic performance using marker
information alone. Such selection would substantially
accelerate the breeding cycle, enhancing gains per unit
time. It would dramatically change the role of phenotyping,
which would then serve to update prediction models and no
longer to select lines. While research to date shows the
exceptional promise of GS, work remains to be done to
validate it empirically and to incorporate it into breeding
schemes.
Source:
http://crop.scijournals.org/cgi/content/abstract/49/1/1
Published online 28 January 2009
Published in Crop Sci 49:1-12 (2009)
© 2009
Crop Science Society of America
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