Dataset Information

Optimized breeding strategies to harness genetic resources with different performance levels.

ABSTRACT:

Background

The narrow genetic base of elite germplasm compromises long-term genetic gain and increases the vulnerability to biotic and abiotic stresses in unpredictable environmental conditions. Therefore, an efficient strategy is required to broaden the genetic base of commercial breeding programs while not compromising short-term variety release. Optimal cross selection aims at identifying the optimal set of crosses that balances the expected genetic value and diversity. We propose to consider genomic selection and optimal cross selection to recurrently improve genetic resources (i.e. pre-breeding), to bridge the improved genetic resources with elites (i.e. bridging), and to manage introductions into the elite breeding population. Optimal cross selection is particularly adapted to jointly identify bridging, introduction and elite crosses to ensure an overall consistency of the genetic base broadening strategy.

Results

We compared simulated breeding programs introducing donors with different performance levels, directly or indirectly after bridging. We also evaluated the effect of the training set composition on the success of introductions. We observed that with recurrent introductions of improved donors, it is possible to maintain the genetic diversity and increase mid- and long-term performances with only limited penalty at short-term. Considering a bridging step yielded significantly higher mid- and long-term genetic gain when introducing low performing donors. The results also suggested to consider marker effects estimated with a broad training population including donor by elite and elite by elite progeny to identify bridging, introduction and elite crosses.

Conclusion

Results of this study provide guidelines on how to harness polygenic variation present in genetic resources to broaden elite germplasm.

SUBMITTER: Allier A

PROVIDER: S-EPMC7216646 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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Publications

Optimized breeding strategies to harness genetic resources with different performance levels.

Allier Antoine A Teyssèdre Simon S Lehermeier Christina C Moreau Laurence L Charcosset Alain A

BMC genomics 20200511 1

<h4>Background</h4>The narrow genetic base of elite germplasm compromises long-term genetic gain and increases the vulnerability to biotic and abiotic stresses in unpredictable environmental conditions. Therefore, an efficient strategy is required to broaden the genetic base of commercial breeding programs while not compromising short-term variety release. Optimal cross selection aims at identifying the optimal set of crosses that balances the expected genetic value and diversity. We propose to ...[more]

PMID: 32393177

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Dataset Information

Optimized breeding strategies to harness genetic resources with different performance levels.

Background

Results

Conclusion

Publications

Optimized breeding strategies to harness genetic resources with different performance levels.

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