WP Leader: Jean-Eric Dheu (Limagrain)
Partners involved: Limagrain, INRA-IGEPP, INRA-GAEL, Biogemma, Terres Inovia (ex-Cetiom), Euralis, Maïsadour, RAGT 2n and Syngenta Seeds

Objectives
WP4 objectives are to validate the outcomes of the previous WP1, WP2, WP3 and WP5 in elite winter OSR germplasm and to introgress new efficient alleles for NUE improvement to speed up the genetic progress in commercial breeding programs through MAS strategy. This will allow 1) rapid delivery of improved varieties for NUE to international and/or national markets and 2) efficient methods for NUE-related germplasm characterization for further gene discovery approaches and breeding strategies. Once validated in WP4, the tools and germplasm will be ready and available for new approaches in breeding approaches by the RAPSODYN partners especially for development of adapted hybrid lines. WP4 will also integrate the analysis of the technical and economic conditions that favor the development of new OSR varieties with higher NUE.
WP4 will demonstrate the usefulness of the information (genomics, physiology, bio-informatics …) and tools produced in the other WPs to develop novel breeding strategies that will enable partners to address the challenge of high performance and sustainable OSR production.

WP4 will:
1- Sort out the candidate genes/regions from WP2 and WP3 to validate them for breeding purposes using diagnostic markers.
2- Assess 10 alleles/QTL involved in NUE and oil yield under N constraints in 5 different elite genetic backgrounds.
3- Assess allele/QTL effect in hybrids.
4- Calculation of a genetic calibration, applied on targeted traits (oil yield under N constraints, differential of yield under N+/N-, etc.) for improved NUE.
5- Validate phenotyping tools assessed in WP2.
6- Analyse the technical and economic conditions that favour the development of new OSR varieties with higher NUE.