Genetic and agronomic contributions to yield gains: A case study for wheat

Genetic and agronomic contributions to yield gains for wheat (Triticum aestivum L.) in the Yaqui Valley of northwest Mexico were estimated for the period from 1968–1990. Five problems associated with estimating sources of yield gains were considered, namely: (1) adjusting yield gains for variation in weather over the study period; (2) considering annual cultivar-by-weather interactions, which are potentially problematic when relative yields of...