Is Estonian barley ready to tackle climate change-induced water regimes?

Abstract

The objective was to examine the effect of drought and flood on barley plants' biomass and growth rate in early vegetative development while comparing the stress adaption of different varieties. A greenhouse trial was conducted in the Estonian Crop Research Institute (ECRI) in 2021, where five Estonian grown spring barley varieties were grown in optimal, drought and flood treatments for six weeks to measure plants' projected leaf area (PA) and relative growth rate (RGR) through phenotyping. Both drought and flooding stress have a strong negative impact on plant biomass in early vegetative growth phases, causing PA at the end of the trial to decrease 26% and 49% respectively. Meanwhile, RGR throughout the trial decreased 6% in drought treatment and 16% in flood treatment. This indicates the greater impact of flood stress on plant's growth compared to drought stress. Genetic variation related to adaption to extreme water regimes in varieties is rather low, especially in drought stress conditions. In drought treatment, the variation coefficient (CV) was 14%, and in flood treatment 25%. Even as most varieties' PA and RGR varied between treatments, the difference between varieties in specific stress treatments was minimal. Estonian grown spring barley varieties are susceptible to extreme water regime related stress caused by potential climate change. This indicates the importance of assessing water-related stress tolerance in breeding material, adapting more accurate innovative evaluation approaches, and integrating climate-resilient genetic material into breeding programs, to hedge the risk caused by unfavourable growth environments in Estonian barley production.

Keywords

• abiotic stress
• biomass
• drought
• flood
• vegetative growth