Integrative analysis of plant responses to a combination of water deficit, heat stress and eCO2 reveals a role for OST1 and SLAH3 in regulating stomatal responses
Authors: Pelaez-Vico, M. A., Sinha, R., Ghani, A., Lopez-Climent, M. F., Joshi, T., Fritschi, F. B., Zandalinas, S. I., Mittler, R.
The study examined how Arabidopsis thaliana integrates physiological, genetic, hormonal, and transcriptomic responses to combined water deficit, heat stress, and elevated CO2. Results show that stomatal aperture under these complex stress combinations is governed by a specific set of regulators, including nitric oxide, OPEN STOMATA 1, and the SLAH3 anion channel, distinct from those active under simpler stress conditions. This reveals a hierarchical stomatal stress code that could inform future research on plant resilience to global change.
Transcriptomic and physiological responses of soybean plants subjected to a combination of water deficit and heat stress under field conditions
Authors: Sinha, R., Pelaez-Vico, M. A., Dhakal, S., Ghani, A., Myers, R., Verma, M., Shostak, B., Ogden, A., Krueger, C. B., Costa Netto, J. R., Zandalinas, S. I., Joshi, T., Fritschi, F. B., Mittler, R.
A two‑year field study examined how soybean (Glycine max) vegetative and reproductive tissues respond transcriptionally and physiologically to water deficit, heat, and their combination. The field‑grown plants showed distinct transcriptomic patterns compared with controlled‑environment studies, especially under single stresses, while differential leaf‑pod transpiration observed in growth chambers was also present in the field. The generated transcriptomic dataset highlights the importance of field‑based omics for understanding crop stress responses.
The study examines how the SnRK1 catalytic subunit KIN10 integrates carbon availability with root growth regulation in Arabidopsis thaliana. Loss of KIN10 reduces glucose‑induced inhibition of root elongation and triggers widespread transcriptional reprogramming of metabolic and hormonal pathways, notably affecting auxin and jasmonate signaling under sucrose supplementation. These findings highlight KIN10 as a central hub linking energy status to developmental and environmental cues in roots.
The study evaluated how acute heat stress affects early-stage rice seedlings, identifying a critical temperature threshold that impairs growth. Transcriptomic profiling of shoots and roots revealed ethylene‑responsive factors (ERFs) as central regulators, with ethylene and jasmonic acid acting upstream, and pre‑treatment with these hormones mitigated heat damage. These findings highlight ERF‑hormone interaction networks as targets for improving rice heat resilience.
The study shows that heatwaves impair the ability of apple (Malus domestica) to mount ASM‑induced immunity against fire blight and apple scab, leading to a loss of protective gene expression. Transcriptomic analysis revealed a broad suppression of ASM‑regulated defense and other biological processes under high temperature, identifying thermo‑sensitive resistance and susceptibility marker genes. The findings highlight that elevated temperature both weakens plant defenses and creates a more favorable environment for pathogens.
Arabidopsis root lipid droplets are hubs for membrane homeostasis under heat stress, and triterpenoid synthesis and storage.
Authors: Scholz, P., Dabisch, J., Clews, A. C., Niemeyer, P. W., Vilchez, A. C., Lim, M. S. S., Sun, S., Hembach, L., Dreier, F., Blersch, K., Preuss, L., Bonin, M., Lesch, E., Iwai, Y., Shimada, T., Eirich, J., Finkemeier, I., Gutbrod, K., Doermann, P., Wang, Y., Mullen, R. T., Ischebeck, T.
The study examined how heat stress alters lipid droplet (LD) number and composition in Arabidopsis thaliana roots, revealing degradation of membrane lipids and accumulation of TAGs and LDs. Proteomic and lipidomic analyses of LDs from a specific Arabidopsis mutant identified novel LD-associated proteins, including triterpene biosynthetic enzymes, whose substrates and products also accumulate in LDs, indicating LDs function as both sinks and sources during stress‑induced membrane remodeling and specialized metabolism.
The study generated a high-quality reference genome for the orphan vegetable Amaranthus tricolor using Illumina and PacBio sequencing, and combined this with a core collection to explore the genetic regulation of betalain biosynthesis under optimal and heat‑stress conditions. Transcriptomic analyses identified candidate gene ATR1.0ch03g000565 associated with CYP76AD1 as a key regulator, and revealed that heat stress down‑regulates CYP76AD1 and 5GT while up‑regulating cDOPA, leading to reduced betacyanin production.
Chromatin accessibility profiling and transcriptomics of Marchantia polymorpha heat‑shock transcription factor (HSF) mutants reveal that HSFA1 governs the placement of cis‑regulatory elements for heat‑induced gene activation, a mechanism conserved across plants, mice, and humans. Integrated gene regulatory network modeling identifies MpWRKY10 and MpABI5B as indirect regulators linking phenylpropanoid and stress pathways, while abscisic acid influences gene expression downstream of HSFA1 without broadly reshaping chromatin. A cross‑species, cross‑condition machine‑learning framework successfully predicts chromatin accessibility and expression, underscoring a conserved regulatory logic in stress responses.
This review compiles experimental studies on wheat to assess how elevated CO₂, higher temperatures, and water deficit interact and affect productivity and water use. By calculating plasticity indices, the authors find that despite CO₂‑induced gains, overall yield generally declines under combined stress, while water consumption often decreases. They highlight the need for more data to improve and validate crop models under future climate scenarios.
The study demonstrates that differential transpiration (DT), wherein vegetative tissues reduce water loss while reproductive tissues maintain transpiration, occurs across most leaf developmental stages of soybean under combined water deficit and heat stress, even at extreme conditions (18% field water capacity and 42°C). DT effectively cools reproductive organs, protecting them from heat-induced damage, and may also function under milder water deficits during heat waves.