The study investigates how the timing of the vegetative phase change (VPC) in Arabidopsis thaliana influences drought adaptation, revealing strong genotype-by-environment interactions that create stage-specific fitness tradeoffs. Genotypes from warmer, drier Iberian climates transition earlier, and genome-wide association mapping identifies loci linked to VPC timing and drought response, with several candidates validated using T‑DNA insertion lines.
The study reveals that the Arabidopsis O-GlcNAc transferase SEC is essential for timely ABA‑induced stomatal closure and drought tolerance, with sec-5 mutants showing delayed closure and increased water loss, while SEC overexpression enhances responsiveness. SEC influences guard‑cell microtubule remodeling, as loss of SEC impairs microtubule reorganization and SEC directly interacts with tubulin α‑4, suggesting tubulin as a target of O‑GlcNAcylation.
Unravelling the intraspecific variation in drought responses in seedlings of European black pine (Pinus nigra J.F. Arnold)
Authors: Ahmad, M., Hammerbacher, A., Priemer, C., Ciceu, A., Karolak, M., Mader, S., Olsson, S., Schinnerl, J., Seitner, S., Schoendorfer, S., Helfenbein, P., Jakub, J., Breuer, M., Espinosa, A., Caballero, T., Ganthaler, A., Mayr, S., Grosskinsky, D. K., Wienkoop, S., Schueler, S., Trujillo-Moya, C., van Loo, M.
The study examined drought tolerance across nine provenances of the conifer Pinus nigra using high‑throughput phenotyping combined with metabolomic and transcriptomic analyses under controlled soil‑drying conditions. Drought tolerance, measured by the decline in Fv/Fm, varied among provenances but was not linked to a climatic gradient and was independent of growth, with tolerant provenances showing distinct flavonoid and diterpene profiles and provenance‑specific gene expression patterns. Integrating phenotypic and molecular data revealed metabolic signatures underlying drought adaptation in this non‑model conifer.
The study compared physiological and transcriptomic responses of poplar trees colonized by the ectomycorrhizal fungi Paxillus involutus or Cenococcum geophilum under normal, drought, and recovery conditions. Cenococcum-colonized plants showed constitutive up‑regulation of heat‑shock proteins, galactinol synthase, and aquaporins and maintained water status and photosynthesis during severe drought, whereas Paxillus colonization promoted growth and nitrogen‑use efficiency and enabled rapid recovery through drought‑induced leaf shedding. These contrasting strategies illustrate species‑specific positions on the growth‑defense trade‑off in ectomycorrhizal symbiosis.
The study used host-mediated artificial selection to iteratively enrich rice-associated microbiomes that improve growth and drought tolerance, starting from diverse soil microbial communities. Over multiple generations, selected microbiomes converged, and amplicon sequencing along with metagenome-assembled genomes identified specific bacterial taxa and functional pathways (e.g., glycerol-3-phosphate and iron transport) linked to enhanced drought performance. The results demonstrate the effectiveness of plant phenotype-driven microbiome engineering for crop improvement.
The study developed a high-throughput phenotyping platform to assess root infestation by Orobanche cumana in a diverse sunflower association mapping population and applied a dual GWAS using SNPs and k-mers to uncover resistance loci. It validated known QTLs with higher resolution, identified novel candidate genes such as leucine‑rich repeat receptor kinases, and highlighted introgressed segments from wild Helianthus species that contribute to broomrape resistance.
The study presents an optimized Agrobacterium-mediated transformation protocol for bread wheat that incorporates a GRF4‑GIF1 fusion to enhance regeneration and achieve genotype‑independent transformation across multiple cultivars. The approach consistently improves transformation efficiency while limiting pleiotropic effects, offering a versatile platform for functional genomics and gene editing in wheat.
Comparative gene regulatory network mapping of Brassicaceae members with differential drought tolerance
Authors: Pandiarajan, R., Lin, C.-W., Sauer, M., Rothballer, S. T., Marin-de la Rosa, N., Schwehn, P., Papadopoulou, E., Mairhormann, B., Falter-Braun, P.
The study mapped drought‑responsive gene regulatory networks in Arabidopsis thaliana, its tolerant relative Arabidopsis lyrata, and Eutrema salsugineum using yeast one‑hybrid screens of orthologous promoters, revealing higher network connectivity and specific TF‑promoter interactions in the tolerant species. Notable findings include an Esa‑specific expansion of bZIP interactions, differential ABA‑signalling edges, and the identification of ASIL2 as a novel stress‑responsive factor, providing a comparative framework for improving crop drought tolerance.
An Axiom SNP genotyping array for potato: development, evaluation and applications
Authors: Baig, N., Thelen, K., Ayenan, M. A. T., Hartje, S., Obeng-Hinneh, E., Zgadzaj, R., Renner, J., Muders, K., Truberg, B., Rosen, A., Prigge, V., Bruckmueller, J., Luebeck, J., Van Inghelandt, D., Stich, B.
The study reports the creation and validation of a high‑density Axiom SNP array for Solanum tuberosum, based on 10X Genomics sequencing of 108 diverse clones and integration of existing Illumina markers. The array demonstrated high reproducibility and, after filtering, provided 206,616 informative markers for population structure analysis, GWAS of polyphenol oxidase activity, and genomic prediction with accuracies up to 0.86.
Identification of a novel link connecting indole-3-acetamide with abscisic acid biosynthesis and signaling
Authors: Moya-Cuevas, J., Ortiz-Garcia, P., Gonzalez Ortega-Villizan, A., Viguera-Leza, I., Perez-Gonzalez, A., Paz-Ares, J., Alonso-Blanco, C., Vicente-Carbajosa, J., Pollmann, S.
A genome-wide association study of 166 Iberian Arabidopsis accessions identified loci, including ABA3 and GA2ox2, that modulate the inhibitory effect of the auxin precursor indole-3-acetamide (IAM) on primary root elongation. Integrating sequence analysis, transcriptomics, 3D protein modeling, and mutant physiology revealed that IAM promotes ABA biosynthesis and signaling, uncovering a novel node of hormone crosstalk.