Barley yield formation under abiotic stress depends on the interplay between flowering time genes and environmental cues

In a field trial across five locations worldwide, we tested three abiotic stresses, nitrogen deficiency, drought and salinity. Barley flowering time genes Ppd-H1, Sdw1, Vrn-H1 and Vrn-H3 exert pleiotropic effects on plant development and grain yield. Under field conditions, these effects are strongly influenced by environmental cues like day length and temperature. The observed yield increase is accompanied by pleiotropic effects of Ppd-H1 resulting in shorter life cycle, extended grain filling period and increased grain size. Adequate timing of plant development is crucial to maximize yield formation under harsh environmental conditions. Wild barley alleles, introgressed into elite barley cultivars, can be utilized to support grain yield formation.