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 engineers Type‑B response regulators to alter their transcriptional activity and cytokinin sensitivity, enabling precise modulation of cytokinin‑dependent traits. Using tissue‑specific promoters, the synthetic transcription factors were deployed in Arabidopsis thaliana to reliably increase or decrease lateral root numbers, demonstrating a modular platform for controlling developmental phenotypes.
Exogenous Hormone Treatments Reveal Species-Specific Regulation of Individual Components of Root Architecture and Salt Ion Accumulation in Cultivated and Wild Tomatoes
Authors: Rahmati-Ishka, M., Craft, E., Pineros, M., Julkowska, M. M.
The study examined how individual hormone treatments (auxin, ethylene, gibberellin) influence root architecture and ion accumulation under salt stress in three tomato accessions, revealing species-specific hormonal effects on lateral root development and Na/K ratios. Genetic analyses using Arabidopsis mutants and a tomato ethylene‑perception mutant (nr) identified novel hormonal signaling components that modulate salt stress responses, highlighting potential strategies to improve crop performance.
The study performs a bibliometric analysis of 1,702 Scopus-indexed tomato omics publications over two decades, revealing a rapid surge in output after 2017 and highlighting dominant fields such as biochemistry, genetics, and molecular biology. Citation and co‑authorship network analyses identify key contributions in microRNA research and genome sequencing, major research hubs, and collaborative clusters, while keyword mapping underscores stress response, fruit quality, and immunity as priority topics.
The study characterizes the tomato class B heat shock factor SlHSFB3a, revealing its age‑dependent expression in roots and its role in enhancing lateral root density by modulating auxin homeostasis. Overexpression of SlHSFB3a increases lateral root emergence, while CRISPR‑mediated knockouts produce the opposite phenotype, indicating that SlHSFB3a regulates auxin signaling through repression of auxin repressors and activation of the ARF7/LOB20 pathway.
The study evaluated how light, vapor pressure deficit, and temperature affect carbon assimilation in four Brazilian Saccharum officinarum varieties over a 530‑day field trial, using diurnal measurements and statistical modeling. Polynomial and multiple linear regression models accurately predicted photosynthetic rates, identifying optimal conditions (PAR ~1800 µmol m⁻² s⁻¹, VPD 2.34 kPa, temperature ~32.5 °C) and explaining up to 60% of the variability.
The study functionally characterizes three tomato CNR/FWL proteins (SlFWL2, SlFWL4, SlFWL5) and demonstrates that SlFWL5 localizes to plasmodesmata, where it regulates leaf size and morphology by promoting cell expansion likely through cell‑to‑cell communication. Gain‑ and loss‑of‑function transgenic tomato lines reveal that SlFWL5 is a key regulator of organ growth via modulation of plasmodesmatal signaling.
The study develops an updated genome-scale metabolic model of tomato leaf (CBZ_iSL3433) incorporating carbamazepine (CBZ) transformation reactions to simulate the pollutant's stress impact under phototrophic conditions. Constraint-based analysis predicts significant reductions in biomass and altered fluxes in nutrient assimilation and secondary metabolism, which are largely ameliorated by biostimulants such as proline, spermine, glycerol, and ethanol. This framework demonstrates a systems-level approach for screening strategies to mitigate pharmaceutical pollutant stress in crops.