Yield, morphology and physiology of winter wheat in high-yielding conditions

Abstract Much has been written on the topic of plant morphology and its relationship to yield but the results have not always been consistent. Most of the experiments were not conducted at normal plant densities, in high-yielding conditions in the field. Work done in, or in connection with, Louvain-la-Neuve showed that morphology was associated with yield per ear, not yield per m 2 . Relationships observed when comparing genotypes were similar to those concerning shoot to shoot variations within single plots. Responses to partial defoliation, spikelet removal and vein cutting showed little association with yield or morphological characters. No close relationships were found between yield per ear and relative growth rate of ear primordia. When a collection of old and new cultivars was investigated in Sweden no systematic change in yield or yield components appeared to have occurred due to selection throughout the century, if lodging and diseases were avoided.