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.
The study conducted a genome-wide characterization of 247 lectin genes in tomato, revealing diverse domain architectures and evolutionary patterns shaped by whole-genome and small-scale duplications. Functional assays using virus-induced gene silencing demonstrated that two GNA-type chimerolectins act as negative regulators of immunity, with silencing enhancing resistance to Ralstonia solanacearum. These results underscore the structural innovation and immune-regulatory roles of lectin genes, offering targets for disease‑resistant tomato breeding.
The study applied a progressive, sublethal drought treatment to Arabidopsis thaliana, collecting time‑resolved phenotypic and transcriptomic data. Machine‑learning analysis revealed distinct drought stages driven by multiple overlapping transcriptional programs that intersect with plant aging, and identified high‑explanatory‑power transcripts as biomarkers rather than causal agents.
The study examined how increasing copper concentrations affect root tip cells of Solanum lycopersicum, revealing that mitochondria are the first organelles to exhibit fragmentation, depolarization, and ROS accumulation, which trigger stress signaling cascades. Copper exposure also caused pronounced nuclear alterations, including chromatin condensation marked by reduced H3K4me3, nuclear shrinkage, and eventual cell death, highlighting chromatin remodeling as a key indicator of copper toxicity.
The study reveals a binary VOC chemotype in cultivated upland cotton, where genotypes exclusively produce either bisabolene or guaiene sesquiterpenes, and links these chemotypes to differential drought responses. Drought stress altered water loss, total terpene levels, and green leaf volatile biosynthesis in a chemotype-specific manner, highlighting chemotypic profiles as potential non‑destructive biomarkers for breeding drought‑resilient cotton.
The study compared leaf‑level physiological responses to a severe summer drought in two Pinus radiata stands differing in management history and age, revealing that younger, managed trees depend on soil nutrients for photosynthetic performance, whereas older, abandoned trees maintain function despite nutrient scarcity. These findings suggest that mature, abandoned stands possess age‑related traits and higher soil organic carbon that buffer drought and nutrient stress, highlighting the value of integrating soil‑leaf interactions into forest management.
The study examined soybean (Glycine max) responses to simultaneous drought and Asian soybean rust infection using combined transcriptomic and metabolomic analyses. Weighted Gene Co-expression Network Analysis identified stress-specific gene modules linked to metabolites, while Copula Graphical Models uncovered sparse, condition‑specific networks, revealing distinct molecular signatures for each stress without overlapping genes or metabolites. The integrative approach underscores a hierarchical, modular defense architecture and suggests targets for breeding multi‑stress resilient soybeans.