Sink-strength determines differences in performance between bread and durum wheat

Our study indicates that the consistent species-by-environment interaction for yield is the consequence of a few traits related to sink-strength that are determined around anthesis. Thus, differences in the spike weight and N accumulated at anthesis, which produced important variations in the number of grains and presumably generated differences in sink-strength, seemed to be involved. This conclusion is supported by the strong relationship between grain yield and the biomass produced during grain filling, in addition to the fact that the variation in individual grain weight, as well as its rate or the duration of grain filling, was poorly related to yield and the post-anthesis biomass.