INRA (P6)

 Institut Jean-Pierre Bourgin (IJPB) Versailles

Maize quantitative genetics for improving biomass saccharification potential (WP1)

Matthieu Reymond is the WP manager. Yves Barrière and Valérie Méchin in our institute have been studying for many years the genetic determinism of the digestibility of corn stover in the gut of ruminants. Mapping populations derived from crosses between contrasting genotypes have been developed and many QTLs for digestibility identified. We will first study how the digestibility relates to the saccharification potential studied in the SUNLIBB program. Variation in stover digestibility is often reflected in the internode anatomy. E.g. Fig. 1, shows transverse sections through the internodes of contrasting maize genotypes. Lignified parts are in red, poorly lignified parts are blue. Next we will exploit the genetic resources to identify and clone QTLs underlying saccharification potential. This should provide original strategies for the manipulation of this trait not only in maize, but also in miscanthus and sugarcane varieties. In this work, we will in particular pay attention to the trade off between agronomic performance in different environments and industrial performance of the biomass. 

   
Fig 1. Transverse sections through the internodes of contrasting maize genotypes.
Lignified parts are in red, poorly lignified parts are blue.

Transcriptomics for identification candidate genes for saccharification potential in maize (WP2)

Herman Höfte is the WP2 manager. Our institute will use transcriptomics resources in maize to guide the identification of candidate genes underlying genetic variation in saccharification potential. 

We also will have small contributions to WP3 and 5, mainly in the analysis of sugars and lignin and the study of the deconstruction of the walls of contrasting maize and miscanthus genotypes.