When drought meets heat – a plant omics perspective

Abstract

Changes in weather patterns with emerging drought risks and rising global temperature are widespread and negatively affect crop growth and productivity. In nature, plants are simultaneously exposed to multiple biotic and abiotic stresses, but most studies focus on individual stress conditions. However, the simultaneous occurrence of different stresses impacts plant growth and development differently than a single stress. Plants sense the different stress combinations in the same or in different tissues, which could induce specific systemic signalling and acclimation responses; impacting different stress-responsive transcripts, protein abundance and modifications, and metabolites. This mini-review focuses on the combination of drought and heat, two abiotic stress conditions that often occur together. Recent omics studies indicate common or independent regulators involved in heat or drought stress responses. Here, we summarize the current research results, highlight gaps in our knowledge, and flag potential future focus areas.

Performance of ACCase-Resistant and ACCase-Susceptible Phenotypes of Sterile Oat Avena sterilis subsp. ludoviciana (Durieu) Nyman under Drought Conditions in the Greenhouse

“…Previous research in wheat has highlighted that drought stress can lower leaf chlorophyll levels by 9%, consequently lowering the photosynthetic rate [46]. This significant alteration in plant physiology due to drought stress translates into reduced plant height, decreased growth rates, fewer tillers, lowered relative water content, diminished seed quality, and, ultimately, significant yield reductions [22]. Plants need to adapt their photosynthetic systems in response to environmental pressures [47].…”

“…These complex weather phenomena, characterized by their unpredictability and severity, jeopardize the resilience of agricultural practices and threaten consistent food supply. Weather patterns are changing due to increasing drought threats and enhancing global temperatures, which is having a detrimental impact on plant growth and productivity [22]. Drought tolerance in plants relies on modifying the photosynthetic system to changing conditions caused by water scarcity [23].…”

The impact of multifactorial stress combination on plants, crops, and ecosystems: how should we prepare for what comes next?

“…In addition to stomatal responses, MFSC was shown to have an overall negative effect on other physiological and metabolic processes such as photosynthesis (Hamann, Denney, et al, 2021;Pascual et al, 2023;Pel aez-Vico et al, 2023;Xu et al, 2023) and the accumulation of different osmo-protectants (e.g., proline; Pascual et al, 2023; Figure 2b). These were further associated with an overall decrease in plant growth rate, height, biomass, and yield (Pascual et al, 2023;Pel aez-Vico et al, 2023).…”

“…Examples of such ‘abiotic stress combination’ events include prolonged droughts combined with heat waves, a heat wave occurring during or following a flood, and alternating cycles of droughts and floods. In multiple studies to date, it was found that in many instances the combination of two different abiotic stresses has a significantly higher negative impact on plant and crop growth and yield, compared to each of the different stress conditions applied individually (e.g., Azodi et al., 2020; Balfagón et al., 2019; Cohen et al., 2021; Gillespie et al., 2012; Orians et al., 2019; Rizhsky et al., 2004; Ruiz‐Vera et al., 2015; Shaar‐Moshe et al., 2019; Sinha et al., 2021; Sinha, Peláez‐Vico, et al., 2023; Slafer & Savin, 2018; Thomey et al., 2019; Xu et al., 2023; Zandalinas et al., 2018; Zinta et al., 2014).…”