Four barley genotypes were examined under simultaneous Fusarium culmorum infection and drought, revealing genotype-dependent Fusarium Head Blight severity and largely additive transcriptomic responses dominated by drought. Co‑expression and hormone profiling linked ABA and auxin to stress‑specific gene modules, and a multiple linear regression model accurately predicted combined‑stress gene expression from single‑stress data, suggesting modular regulation.
The mRNA covalent modification dihydrouridine regulates transcript turnover and photosynthetic capacity during plant abiotic stress
Authors: Yu, L., Melandri, G., Dittrich, A. C., Calleja, S., Rozzi, B., Ganguly, D. R., Palos, K., Srinivasan, A., Brewer, E. K., Fischer, H., Obata, T., Elgawad, H. A., Beemster, G. T. S., Henderson, R., Garcia, C. D., Zhang, X., Stern, D., Eveland, A., Schroeder, S. J., Skirycz, A., Lyons, E., Arnold, E. A., Gregory, B. D., Nelson, A. D. L., Pauli, D.
The study integrates multi-omics data from six Sorghum bicolor accessions under field drought to link RNA covalent modifications (RCMs) with photosynthetic performance, identifying the enzyme SbDUS2 that produces dihydrouridine (DHU) on transcripts. Loss‑of‑function dus2 mutants in Arabidopsis thaliana reveal that DHU deficiency leads to hyperstability of photosynthesis‑related mRNAs, impairing germination, development, and stress‑induced CO2 assimilation. The authors propose DHU as a post‑transcriptional mark that promotes rapid mRNA turnover during abiotic stress, enhancing plant resilience.
The study integrated 16 Arabidopsis thaliana whole‑genome bisulfite sequencing datasets from 13 stress experiments using a unified bioinformatic pipeline to map common and stress‑specific DNA methylation changes. Differentially methylated regions varied by stress type and methylation context, with CG DMRs enriched in gene bodies and CHG/CHH DMRs in transposable elements, some of which overlapped loci prone to stable epimutations. Gene ontology and TE enrichment analyses highlighted shared stress pathways and suggest environmental stress can generate heritable epigenetic variation.
High-quality PacBio HiFi draft genome assemblies were generated for three Bouteloua species (B. curtipendula, B. gracilis, B. eriopoda) with >98.5% BUSCO completeness. Gene prediction with Helixer produced inflated gene counts likely reflecting polyploidy and fragmented predictions, and panEDTA identified 25–40% transposable-element content dominated by LTR retrotransposons. These assemblies provide foundational references for comparative genomics within PACMAD grasses.
The study employed immunofluorescence labeling and fluorescence intensity quantification to examine tissue-specific cellular modifications in plants under drought stress, revealing targeted alterations in proteoglycans, polysaccharides, and AGPs in leaves and roots. These findings highlight the importance of in planta analyses for accurately capturing stress-induced structural changes.
The study discovers that drought stress triggers proteolytic activation of chloroplast‑localized polyphenol oxidase (PPO) in Camellia sinensis, converting catechins into theaflavins that act as signaling molecules to induce an unfolded protein response and IRE1‑bZIP60‑dependent programmed cell death. Germplasm comparison, transcriptomic profiling, virus‑induced silencing, PPO overexpression, and pharmacological feeding experiments demonstrate that this PPO‑theaflavin pathway is a conserved stress sensor across species such as tomato and wheat.
The study applied single-nucleus RNA sequencing to mature Sorghum bicolor leaves under well‑watered and drought conditions, identifying major leaf cell types and their transcriptional responses. Drought induced transcriptomic changes that surpassed cell‑type differences, indicating a common response across mesophyll, bundle sheath, epidermal, vascular, and stomatal cells, and enabling the identification of candidate drought‑responsive regulators for improving water‑use efficiency.
Drought drives reversible disengagement of root-mycorrhizal symbiosis
Authors: Akmakjian, G. Z., Nozue, K., Nakayama, H., Borowsky, A. T., Morris, A. M., Baker, K., Canto-Pastor, A., Paszkowski, U., Sinha, N., Brady, S., Bailey-Serres, J.
The study shows that during drought, rice (Oryza sativa) downregulates nutrient acquisition and arbuscular mycorrhizal (AM) symbiosis genes, causing the fungal partner to enter metabolic quiescence and retract hyphae, but upon re-watering the symbiosis is rapidly reactivated. This reversible dynamic suggests that plant‑fungus mutualisms are fragile under fluctuating water availability.
The study investigated structural cell wall changes in wheat (Triticum aestivum) seedlings during drought, revealing rapid remodeling after five days, organ-specific responses, and both cross‑linking and degradation of wall polymers such as homogalacturonans, xylan, and AGPs. Deposition of unesterified homogalacturonans promotes calcium cross‑linking, enhancing wall rigidity and water retention.
Stress-dependent responses of grapevine wood and fungal pathogen activity under esca and drought
Authors: Chambard, M., Cantu, D., Bortolami, G., Dell'Acqua, N., Ferrer, N., Gambetta, G., Garcia, J., Gastou, P., Massonnet, M., Moretti, S., Rochepeau, A., Petriacq, P., Foulongne-Oriol, M., Delmas, C. E. L.
The study used wood metatranscriptomics, metabolomics, and metabarcoding to compare grapevine (Vitis vinifera) responses to drought and esca leaf symptom expression, revealing distinct but overlapping transcriptomic and metabolic signatures, including activation of phenylpropanoid and stilbenoid pathways. Drought reduced esca symptom expression, associated with decreased abundance of the wood‑decay fungus Fomitiporia mediterranea and altered fungal virulence factor expression, while increasing the relative abundance and anti‑oxidative gene expression of Phaeomoniella chlamydospora.