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Comparative analyses identify the contributions of exotic donors to disease resistance in a barley experimental population.

Fang Z, Eule-Nashoba A, Powers C, Kono TY, Takuno S, Morrell PL, Smith KP - G3 (Bethesda) (2013)

Bottom Line: All three genomic regions have been previously identified by quantitative trait locus (QTL) and association mapping.Based on the degree of identity-by-state relative to donor parents, putative donors of resistance alleles were also identified.The successful application of comparative population genetic approaches in this barley breeding experiment suggests that the approach could be applied to other breeding populations that have undergone defined breeding and selection histories, with the potential to provide valuable information for genetic improvement.

View Article: PubMed Central - PubMed

Affiliation: Department of Agronomy and Plant Genetics, University of Minnesota, St. Paul, Minnesota 55108.

ABSTRACT
Introgression of novel genetic variation into breeding populations is frequently required to facilitate response to new abiotic or biotic pressure. This is particularly true for the introduction of host pathogen resistance in plant breeding. However, the number and genomic location of loci contributed by donor parents are often unknown, complicating efforts to recover desired agronomic phenotypes. We examined allele frequency differentiation in an experimental barley breeding population subject to introgression and subsequent selection for Fusarium head blight resistance. Allele frequency differentiation between the experimental population and the base population identified three primary genomic regions putatively subject to selection for resistance. All three genomic regions have been previously identified by quantitative trait locus (QTL) and association mapping. Based on the degree of identity-by-state relative to donor parents, putative donors of resistance alleles were also identified. The successful application of comparative population genetic approaches in this barley breeding experiment suggests that the approach could be applied to other breeding populations that have undergone defined breeding and selection histories, with the potential to provide valuable information for genetic improvement.

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Related in: MedlinePlus

The boxplots for observed and simulated FST between the Closed and Reopened panels. Simulations were based on demography alone. The dashed horizontal line is the 97.5th percentile of FST in the empirical data.
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fig3: The boxplots for observed and simulated FST between the Closed and Reopened panels. Simulations were based on demography alone. The dashed horizontal line is the 97.5th percentile of FST in the empirical data.

Mentions: Adding the Reopened panel to the simulation, and simulating migration, the estimated migration rate was 4N0m = 4000, which corresponded to 0.01 migrants per generation over 15 generations (Figure S7). In these simulations, in which demography alone impacted allele frequency (i.e., where we were testing a neutral hypothesis), the 97.5th percentile of FST was 0.09 between the simulated Closed and Reopened panel compared with FST of 0.315 in the empirical data (Figure 3). This suggests that in the absence of selection, demography alone is unlikely to produce the extreme values of FST observed between the Closed and Reopened panels.


Comparative analyses identify the contributions of exotic donors to disease resistance in a barley experimental population.

Fang Z, Eule-Nashoba A, Powers C, Kono TY, Takuno S, Morrell PL, Smith KP - G3 (Bethesda) (2013)

The boxplots for observed and simulated FST between the Closed and Reopened panels. Simulations were based on demography alone. The dashed horizontal line is the 97.5th percentile of FST in the empirical data.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3815057&req=5

fig3: The boxplots for observed and simulated FST between the Closed and Reopened panels. Simulations were based on demography alone. The dashed horizontal line is the 97.5th percentile of FST in the empirical data.
Mentions: Adding the Reopened panel to the simulation, and simulating migration, the estimated migration rate was 4N0m = 4000, which corresponded to 0.01 migrants per generation over 15 generations (Figure S7). In these simulations, in which demography alone impacted allele frequency (i.e., where we were testing a neutral hypothesis), the 97.5th percentile of FST was 0.09 between the simulated Closed and Reopened panel compared with FST of 0.315 in the empirical data (Figure 3). This suggests that in the absence of selection, demography alone is unlikely to produce the extreme values of FST observed between the Closed and Reopened panels.

Bottom Line: All three genomic regions have been previously identified by quantitative trait locus (QTL) and association mapping.Based on the degree of identity-by-state relative to donor parents, putative donors of resistance alleles were also identified.The successful application of comparative population genetic approaches in this barley breeding experiment suggests that the approach could be applied to other breeding populations that have undergone defined breeding and selection histories, with the potential to provide valuable information for genetic improvement.

View Article: PubMed Central - PubMed

Affiliation: Department of Agronomy and Plant Genetics, University of Minnesota, St. Paul, Minnesota 55108.

ABSTRACT
Introgression of novel genetic variation into breeding populations is frequently required to facilitate response to new abiotic or biotic pressure. This is particularly true for the introduction of host pathogen resistance in plant breeding. However, the number and genomic location of loci contributed by donor parents are often unknown, complicating efforts to recover desired agronomic phenotypes. We examined allele frequency differentiation in an experimental barley breeding population subject to introgression and subsequent selection for Fusarium head blight resistance. Allele frequency differentiation between the experimental population and the base population identified three primary genomic regions putatively subject to selection for resistance. All three genomic regions have been previously identified by quantitative trait locus (QTL) and association mapping. Based on the degree of identity-by-state relative to donor parents, putative donors of resistance alleles were also identified. The successful application of comparative population genetic approaches in this barley breeding experiment suggests that the approach could be applied to other breeding populations that have undergone defined breeding and selection histories, with the potential to provide valuable information for genetic improvement.

Show MeSH
Related in: MedlinePlus