Key traits associated with potential grain weight in selected CIMCOG genotypes

International audienceTo increase grain yield potential of wheat and breeding efficiency the trade-off between grain number and kernel weight should be minimized by (i) improving the balance between the two main yield components or by (ii) increasing kernel weight potential. The aim of this study was to evaluate the trade-off between kernel weight and grain number and to assess key drivers of kernel weight potential in a selected set of 8 genotypes from the CIMCOG population. These genotypes were evaluated during the 2014/15 seasons in Valdivia (Chile) to confirm previous associations recorded in Ciudad Obregón in the light that contrasting relationships between grain yield and grain number were found in these environments. A lower trade-off between kernel weight and grain number was recorded in Valdivia where higher grain weight was reached. However, individual kernel weight showed a close association with the volume and length of grains in positions G2 and G4. In addition, kernel weight of G4 also showed association with kernel wide. Interestingly, thinning treatments augmenting the availability of resources since booting on increased both grain number and kernel weight