Chilean wheat (Triticum aestivum L.) landraces with greater biomass, yield stability, and intrinsic WUE than modern varieties are an opportunity for adaptation to severe drought areas

In Mediterranean environments, wheat often faces water scarcity during grain filling. The spike growth period may also be affected under severe drought conditions, which are becoming increasingly frequent due to ongoing climate change. Selection for high yield potential has led to yield improvements in wheat under moderate drought conditions, but not under severe drought. Yield stability, biomass, and water-use efficiency (WUE) are important genotypic traits under drought. Under severe drought, landraces represent a valuable source of adaptative traits. In this study, we analyzed yield, stability, biomass and water use efficiency (WUE) in seven Chilean landraces, potentially better adapted to severe drought conditions, and compared them with three modern varieties across 10 contrasting environments, including those affected by severe drought. Chilean landraces analyzed in this study exhibited greater biomass, intrinsic WUE (iWUE), yield stability, and biomass stability than the modern varieties. In one group of landraces, this performance appears to be explained by a longer time to anthesis, while in the other group it would be due to other adaptive traits that warrant further investigation. Yield stability and biomass stability are key traits for adaptation to severe drought, and achieving them requires selection for higher biomass and iWUE. In this context, the Chilean wheat landrace, Furfuya, stands out as a valuable genetic resource for national breeding programs aiming to improve yield and yield stability in Mediterranean environments affected by severe drought.