Quantitative trait locus mapping of root exudate metabolome in a Solanum lycopersicum Moneymaker x S. pimpinellifolium RIL population and their putative links to rhizosphere microbiome
Authors: Kim, B., Kramer, G., Leite, M. F. A., Snoek, B. L., Zancarini, A., Bouwmeester, H.
The study used untargeted metabolomics and QTL mapping in a tomato recombinant inbred line population to characterize root exudate composition and identify genetic loci controlling specific metabolites. It reveals domestication-driven changes in exudate profiles and links metabolic QTLs with previously reported microbial QTLs, suggesting a genetic basis for shaping the root microbiome.
The authors used a bottom‑up thermodynamic modelling framework to investigate how plants decode calcium signals, starting from Ca2+ binding to EF‑hand proteins and extending to higher‑order decoding modules. They identified six universal Ca2+-decoding modules that can explain variations in calcium sensitivity among kinases and provide a theoretical basis for interpreting calcium signal amplitude and frequency in plant cells.
Evaluation of combined root exudate and rhizosphere microbiota sampling approaches to elucidate plant-soil-microbe interaction
Authors: Escudero-Martinez, C., Browne, E. Y., Schwalm, H., Santangeli, M., Brown, M., Brown, L., Roberts, D. M., Duff, A. M., Morris, J., Hedley, P. E., Thorpe, P., Abbott, J. C., Brennan, F., Bulgarelli, D., George, T. S., Oburger, E.
The study benchmarked several sampling approaches for simultaneous profiling of root exudates and rhizosphere microbiota in soil-grown barley, revealing consistent exudate chemistry across methods but variation in root morphology and nitrogen exudation. High‑throughput amplicon sequencing and quantitative PCR showed protocol‑specific impacts on microbial composition, yet most rhizosphere-enriched microbes were captured by all approaches. The authors conclude that different protocols provide comparable integrated data, though methodological differences must be aligned with experimental objectives.
The study combined ecometabolomics of root exudates with fungal community profiling to assess how abiotic (soil moisture, temperature legacy) and biotic (microbial inoculum, plant density) treatments shape metabolite diversity and fungal assemblages in Guarea guidonia seedlings. While soil microbial legacy and moisture drove metabolite diversity, antimicrobial treatments altered metabolite composition, and fungal community structure was linked to metabolite profiles, revealing metabolite‑fungal associations as early indicators of plant response to disturbance.
Tomato leaf transcriptomic changes promoted by long-term water scarcity stress can be largely prevented by a fungal-based biostimulant
Authors: Lopez-Serrano, L., Ferez-Gomez, A., Romero-Aranda, R., Jaime Fernandez, E., Leal Lopez, J., Fernandez Baroja, E., Almagro, G., Dolezal, K., Novak, O., Diaz, L., Bautista, R., Leon Morcillo, R. J., Pozueta Romero, J.
Foliar application of Trichoderma harzianum cell‑free culture filtrates (CF) increased fruit yield, root growth, and photosynthesis in a commercial tomato cultivar under prolonged water deficit in a Mediterranean greenhouse. Integrated physiological, metabolite, and transcriptomic analyses revealed that CF mitigated drought‑induced changes, suppressing about half of water‑stress responsive genes, thereby reducing the plant’s transcriptional sensitivity to water scarcity.
The study investigated how plant roots promote water infiltration through dry soil layers using dye tracing in model soil microcosms. Results indicate that dissolved root exudates, possibly by altering surface tension, are the primary drivers of infiltration, with root architecture also contributing. These insights suggest that root traits influencing exudation and structure could improve drought resistance in crops.
The study examined how altering ethylene biosynthesis (ACO1) or perception (etr1.1) in a hybrid poplar (P. tremula × P. tremuloides T89) influences the assembly of root and shoot fungal and bacterial communities, using amplicon sequencing and confocal microscopy. Ethylene modulation had limited impact on the sterile plant metabolome but triggered distinct primary and secondary metabolic changes in microbe‑colonized plants, correlating with reduced fungal colonisation of shoots and increased root fungal colonisation, while arbuscular mycorrhizal fungi and bacterial communities were largely unchanged.
Transcriptome responses of two Halophila stipulacea seagrass populations from pristine and impacted habitats, to single and combined thermal and excess nutrient stressors, reveal local adaptive features and core stress-response genes
Authors: Nguyen, H. M., Yaakov, B., Beca-Carretero, P., Procaccini, G., Wang, G., Dassanayake, M., Winters, G., Barak, S.
The study examined transcriptomic responses of the tropical seagrass Halophila stipulacea from a pristine and an impacted site under single and combined thermal and excess nutrient stress in mesocosms. Combined stress caused greater gene reprogramming than individual stresses, with thermal effects dominating and the impacted population showing reduced plasticity but higher resilience. Core stress‑response genes were identified as potential early field indicators of environmental stress.