The widespread use of agrochemicals raises concerns about long-term environmental and health effects, increasing the demand for sustainable alternatives. Peptide-hormone signalling, particularly those regulating senescence, holds promise for developing such alternatives in postharvest technologies, however most research remains focused on model species. This study identifies the Lactuca sativa CLAVATA3/ENDOSPERM-SURROUNDING REGION-related (CLE) peptide, LsCLE12p, as a potential postharvest regulator in crops and ornamentals. LsCLE12p interacts with high salinity, abscisic acid (ABA), and ethylene pathways, influencing lettuce development and morphology. Notably, LsCLE12p induces stomatal closure similarly to ABA and transcriptionally modulates immune responses, fluid transport, and senescence-related pathways, suggesting a regulatory role in leaf aging. Consistent with these molecular functions, LsCLE12p delays dark-induced senescence in lettuce and extends the longevity of cut roses. These findings highlight the potential of CLE peptides in non-model species to enhance postharvest shelf life in crops and ornamentals.

Abstract Hyperspectral imaging is an imaging technique that allows for acquisition of high-resolution spectral information beyond that of the visible spectrum. When applied to plants, it effectively enables non-invasive characterization of physiological status and has been widely used in agricultural settings. Marchantia is a model bryophyte species whose flat morphology and visually distinct stress-response phenotypes makes it an ideal candidate for imaging studies. Here, we provide a comprehensive protocol for hyperspectral imaging for Marchantia plants, which encompasses hardware configuration, data acquisition, and computations processing. This protocol features a streamlined data processing pipeline hosted on a web-based development platform that automates 1) the segmentation of plant area into spatially distinct regions for localized analysis of intra-specimen physiological gradients, and 2) classification of plant pixels based on their spectral signatures. All results are exported as structured CSV files for ease of further analysis as desired by the user.

Designing biomaterials compatible with plants and specific payloads enables new technologies for precision agriculture, including targeted and efficient agrochemical delivery. However, broader implementation requires a systematic understanding of the complex interactions among payloads, biomaterial properties, and plant responses to establish foundational design principles that support a sustained biotic–abiotic interface. Using microneedles made of different polymers and microstructures, this study investigates plant–biomaterial interactions to develop effective compound delivery strategies. Biodegradation studies show that microneedle biomaterials impart distinct mechanical strength, hydrophilicity, and surface charge, which influence the release profiles of bioactive cargo. Transcriptomic analyses following microneedle injection reveal mostly universal, but some variable acute responses related to immunity and metabolism, depending on inherent biomaterial properties. Despite these responses, microneedle treatments caused minimal effects on plant growth, chlorophyll content, stomatal conductance, and quantum efficiency of photosystem II. Finally, we demonstrate how biomaterial properties influence the delivery of agrochemicals with distinct chemical and functional characteristics, using hydrophilic plant growth regulator gibberellic acid (GA3) and hydrophobic herbicide pelargonic acid (PA), into tomato and lettuce, supporting the broad applicability of technology. These findings establish principles for engineering plant-biomaterial interfaces to accommodate payloads with diverse characteristics while ensuring plant safety.

Recent advancements in plant sensing technologies have significantly improved agricultural productivity while reducing resource inputs, resulting in higher yields by enabling early disease detection, precise diagnostics, and optimized fertilizer and pesticide applications. Each adopted technology offers unique advantages suitable for various farm operations, breeding programs, and laboratory research. This review article first summarizes key target traits, endogenous structures, and metabolites that serve as focal points for plant diagnostic and sensing technologies. Next, conventional plant sensing technologies based on light reflectance and fluorescence, which rely on foliar phytopigments and fluorophores such as chlorophylls are discussed. These methods, along with advanced analytical strategies incorporating machine learning, enable accurate stress detection and classification beyond general assessments of plant health and stress status. Advanced optical techniques such as Fourier transform infrared spectroscopy (FT-IR) and Raman spectroscopy, which allow specific measurements of various plant metabolites and structural components are then highlighted. Furthermore, the design and applications of nanotechnology chemical sensors capable of highly sensitive and selective detection of specific phytochemicals, including phytohormones and signaling second messengers, which regulate physiological and developmental processes at micro- to sub-micromolar concentrations are introduced. By selecting appropriate sensing methodologies, agricultural production, and relevant research activities can be significantly improved.

Biomaterials bridging the biotic-abiotic interface in plants offer the opportunity to precisely deliver agrochemicals and continuously monitor plant health, with the goals of increasing resilience to climate change, enhancing crop production and mitigating environmental impact. In this study we report the manipulation of silk fibroin assembly with inorganics nucleation at their phase front to nanomanufacture porous and hollow microneedles that can be interfaced with plants. Plant growth analysis and quantification of wounding gene expression show a non-significant systemic wounding response to the injection of silk microneedles in tomato plants. Microneedles with a hollow structure enable the systemic delivery of plant micronutrients to treat chlorosis in tomato plants and crop biofortification through transport of human micronutrients injected in the petiole and loaded into tomato fruits. Hollow microneedles also provide access to plant vasculature for sap sampling, enabling continuous monitoring and early detection of phytoaccumulation of environmental contaminants such as cadmium.

Mediator, a transcriptional coactivator, regulates plant growth and development by interacting with various transcriptional regulators. MEDIATOR15 (MED15) is a subunit in the Mediator complex potentially involved in developmental control. To uncover molecular functions of Arabidopsis MED15 in development, we searched for its interactors. MED15 was found to interact with DELLA proteins, which negatively regulate gibberellic acid (GA) signaling and positively regulate GA biosynthesis. Mutants and overexpressors of MED15 exhibited multiple GA-related growth phenotypes, which resembled the phenotypes of the DELLA overexpressor and mutant, respectively. Consistent with this observation, DELLA protein levels were inversely correlated with MED15 protein levels, suggesting that MED15 activates GA signaling through DELLA degradation. MED15 was required not only for DELLA-mediated induction of GA-biosynthesis gene expression but also for GA-mediated degradation of DELLA. Therefore, MED15 facilitates DELLA destruction not only by promoting GA biosynthesis but also by accelerating DELLA turnover. Furthermore, MED15-mediated GA signaling was required for timely developmental responses to dark and warm conditions. Our results provide insight into developmental control by Mediator via precise regulation of DELLA stability. These findings are potentially useful for the generation of new crop cultivars with ideal body architecture.

This paper highlights the role of various signaling hormones in drought stress tolerance. It explains how phytohormones act and interact under drought conditions. Drought stress significantly impairs plant growth, development and productivity. The likelihood of adverse impacts of drought will increase due to variations in global climate patterns. Phytohormones serve as key regulators of drought tolerance mechanisms in plants. The in-depth understanding of the role and signaling of such hormones is thus of great significance for plant stress management. In this review, we conducted a bibliometric analysis and thematic mapping of recent research on drought and phytohormones, and phytohormone interactions. It is assumed that different classes of phytohormones such as abscisic acid (ABA), auxins (IAA), cytokinins (CTK), ethylene (ETH), gibberellic acid (GA), brassinosteroids (BRs), salicylates (SA), jasmonates (JA), and strigolactones (SLs) play a pivotal role in drought resistance mechanisms in many crops. The present work highlights recent advances in plant responses to drought and uncovers the recent functions of phytohormones in the establishment of drought-specific tolerance strategies. It also deciphers the various interactions between phytohormones allowing plant adaptation to drought stress. Overall, this review highlights recent and original discoveries useful for developing new strategies to improve plant resistance to drought.

Gamma-aminobutyric acid (GABA) is a metabolite involved in plant growth and stress responses, with its synthesis regulated by glutamate decarboxylase (GAD). Plant GAD enzymes have an autoinhibitory α-helix at the C-terminus, which calmodulin (CaM) binding typically relieves. Eliminating this C-terminal motif usually increases GABA levels in crops. In this case study, we generated a CRISPR/Cas9-edited lettuce line with a 14-amino acid deletion in the C-terminal helix of LsGAD2, the isozyme primarily expressed in most tissues. This targeted truncation removes CaM-binding residues while retaining the key Lys cluster (Lys489, Lys490, Lys491) responsible for autoinhibition, resulting in a significant reduction in GABA content without affecting growth. The LsGAD1/2-ΔC line showed a transcriptomic profile resembling stress responses in the wildtype under unstressed conditions. Reduced GABA levels appeared to upregulate genes involved in stress perception, signalling, and defense-related metabolic and hormonal changes, potentially mediated by WRKY-family transcription factors. Likely due to lower GABA levels and altered defense responses, LsGAD1/2-ΔC plants showed increased Agrobacterium-mediated transient expression of β-glucuronidase. Overall, our study suggests that targeted genetic manipulation of the C-terminal helix of GAD enzymes can reduce GABA levels while enhancing transformation efficiency in lettuce, thus presenting a means for engineering for such purposes.

Fluorescent nanosensors operating in planta have shown recent success toward informing basic plant biology and agricultural applications. We developed near-infrared (NIR) fluorescent nanosensors using the Corona Phase Molecular Recognition (CoPhMoRe) technique that distinguish Fe(II) and Fe(III) species with limit of detection as low as 10 nM. An anionic poly(p-phenyleneethynylene) (PPE) polyelectrolyte wrapped single-walled carbon nanotube (SWNT) shows up to 200% turn-on and 85% turn-off responses to Fe(II) and Fe(III), respectively, allowing spatial and temporal analysis of iron uptake in both foliar and root-to-shoot pathways. Our findings reveal species-dependent iron uptake efficiency, mobility, and utilization rates, which we show is primarily affected by the chelation status of iron source and by plant physiological conditions such as iron deficiency and treatment with the stress hormone, abscisic acid (ABA). The broad applicability of this sensor across important plant species highlights the potential of nanotechnology-enabled sensors to enable precise and sustainable nutrient management.

The broad-spectrum herbicide L-phosphinothricin (PPT) irreversibly inhibits glutamine synthetase (GS) activity. Here we present cationic amino acid transporters (CAT) as mediators of PPT accumulation and susceptibility. Comparative analysis of Arabidopsis thaliana, Marchantia polymorpha, rice, and Klebsormidium nitens reveals conserved responses to GS inhibition, with absence of efficient PPT uptake underlying resistance in M. polymorpha. Transcriptomic analysis identifies four candidate transporters in A. thaliana which, when overexpressed in M. polymorpha, confer varying levels of sensitivity corresponding with PPT accumulation. AtCAT1 and AtCAT5 confer the greatest sensitivities and are required for glutamic acid uptake and endogenous nitrogen metabolism in A. thaliana, and PPT susceptibility. Molecular dynamics simulation of AtCAT5 identifies key residues involved in PPT binding, which induce the rotational flexibility of helices H1 and H6 which form an intracellular access tunnel. These findings highlight the natural diversity underlying PPT accumulation and susceptibility, which can guide herbicide resistance management strategies.

Leaf color patterns in nature, shaped by genetic and environmental factors, can be analyzed using hyperspectral reflectance imaging. This protocol details step-by-step procedures for hyperspectral image acquisition, correction of uneven lighting, and spectral component analysis to reveal distinct and sometimes previously undetectable features on leaves. We outline how to identify key spectral components and project hyperspectral cubes onto them to highlight specific spectral traits. For complete details of this protocol, please refer to Krishnamoorthi et al.1.

Protein phosphorylation regulates G protein signaling in plants. AtRGS1 primarily modulates AtGPA1, the canonical Gα subunit in the heterotrimeric G protein complex. AtRGS1 possesses both a seven-transmembrane (7TM) domain connected to a cytoplasmic Regulator of G Protein Signaling domain (RGS box domain) by a flexible linker region. This study presents the novel function of a highly conserved, known phosphorylation site, Ser278, within this linker region utilizing molecular dynamics (MD) simulations with in vivo experimental validation. We show that phosphorylation at Ser278 is crucial for establishing specific AtRGS1 interactions with AtGPA1, primarily by stabilizing the positioning and orientation of the RGS domain within the membrane. Phosphorylation at Ser278 enhances the formation of stable hydrogen bonds between phosphorylated Ser278 and conserved residues within the RGS box domain, influencing the flexibility of RGS domain mobility and thus modulating its interface to AtGPA1. Consistent with the MD simulations, in vivo assays demonstrated that this phosphorylation reduced the binding of AtRGS1 to AtGPA1 and conferred changes in physiology. Specifically, the non-phosphorylation mutation of Ser278 decreased both plant immune responses and AtRGS1 endocytosis evoked by the bacterial effector, flg22. MD simulations and sequence analysis of diverse plant 7TM-RGS proteins suggest conservation of this mechanism across land plants, emphasizing the critical role of this previously overlooked linker region.

Heterotrimeric G proteins,composed of the α,β,and γ subunits,mediate cellular signal pathways in response to external stimuli.The Gα subunit is traditionally viewed as a molecular switch,cycling between a GDP-bound inactive state,where it forms a stable heterotrimer with Gβγ,and a GTP-bound active state,which promotes the dissociation of the heterotrimer into two active signaling components:GTP-bound Gα and the Gβγ dimer.In humans,four distinct Gα protein subtypes interact with specific upstream G protein-coupled receptors and downstream effec-tors to regulate diverse signaling pathways.This signaling spec-ificity arises from gene duplication and subsequent sequence divergence,which enabled distinct coupling preferences to their binding partners.However,such gene expansion and diversifica-tion are absent in the plant G protein system:the Arabidopsis genome encodes only a single canonical Gα gene,GPA1,although there are three atypical extra-large Gα genes,XLG1,-2,and-3.Despite this genetic simplicity,plant heterotrimeric G proteins mediate a wide range of physiological processes,from seed germination and early development to responses against abiotic and biotic stresses.How plants achieve such functional diversity with a single canonical Gα gene has remained a long-standing question(Urano and Jones,2014).

Accurate detection of nutrient deficiency in plant leaves is essential for precision agriculture, enabling early intervention in fertilization, disease, and stress management. This study presents a deep learning framework for leaf anomaly segmentation using multispectral imaging and an enhanced YOLOv5 model with a transformer-based attention head. The model is tailored for processing nine-channel multispectral input and uses self-attention mechanisms to better capture subtle, spatially-distributed symptoms. The plants in the experiments were grown under controlled nutrient stress conditions for evaluation. We carry out extensive experiments to benchmark the proposed model against the baseline YOLOv5. Extensive experiments show that the proposed model significantly outperforms the baseline YOLOv5, with an average Dice score and IoU (Intersection over Union) improvement of about 12

AbstractCovalent organic frameworks designed as chromatic sensors offer opportunities to probe biological interfaces, particularly when combined with biocompatible matrices. Particularly compelling is the prospect of chemical tomography – or the 3D spatial mapping of chemical detail within the complex environment of living systems. Herein, we demonstrate a chromic Covalent Organic Framework (COF) integrated within silk fibroin (SF) microneedles that probe plant vasculature, sense the alkalization of vascular fluid as a biomarker for drought stress, and provide a 3D in-vivo mapping of chemical gradients using smartphone technology. A series of Schiff base COFs with tunable pKa ranging from 5.6 to 7.6 enable conical, optically transparent SF microneedles with COF coatings of 120 to 950 nm to probe vascular fluid and the surrounding tissues of tobacco and tomato plants. The conical design allows for 3D mapping of the chemical environment (such as pH) at standoff distances from the plant, enabling in-vivo chemical tomography. Chromatic COF sensors of this type will enable multidimensional chemical mapping of previously inaccessible and complex environments.

The microbe-associated molecular pattern f1g22 is recognized in a f1agellin-sensitive 2-dependent manner in root tip cells. Here, we show a rapid and massive change in protein abundance and phosphorylation state of the Arabidopsis root cell proteome in WT and a mutant deficient in heterotrimeric G-protein-coupled signaling. f1g22induced changes fall on proteins comprising a subset of this proteome, the heterotrimeric G protein interactome, and on highly-populated hubs of the immunity network. Approximately 95% of the phosphorylation changes in the heterotrimeric G-protein interactome depend, at least partially, on a functional G protein complex. One member of this interactome is ATB alpha, a substrate-recognition subunit of a protein phosphatase 2A complex and an inter- actor to Arabidopsis thaliana Regulator of G Signaling 1 protein (AtRGS1), a f1g22-phosphorylated, 7transmembrane spanning modulator of the nucleotide- binding state of the core G-protein complex. A null mutation of ATB alpha strongly increases basal endocytosis of AtRGS1. AtRGS1 steady-state protein level is lower in the atb alpha mutant in a proteasome-dependent manner. We propose that phosphorylation-dependent endocytosis of AtRGS1 is part of the mechanism to degrade AtRGS1, thus sustaining activation of the heterotrimeric G protein complex required for the regulation of system dynamics in innate immunity. The PP2A(ATB alpha) complex is a critical regulator of this signaling pathway.

Plant responses to nitrate, phosphate and sucrose form a complex molecular network crucial for terrestrial adaptation. However, the origins, functional diversity and evolvability of this network during plant terrestrialization remain scarcely understood. Here we compare the transcriptomic response to these nutrients in the bryophyte Marchantia polymorpha and the streptophyte alga Klebsormidium nitens. We show that the largely species-specific nutrient response pattern is driven by gene regulatory network (GRN) alterations. Intriguingly, while pathways governing the GRNs exhibit modest conservation, M. polymorpha GRNs exhibit more regulatory connections through the redeployment of ancient transcription factor CSD. In M. polymorpha, functional analyses reveal the involvement of pre-existing cytokinin machineries in downstream targets, orchestrating plastic morpho-physiological responses to nutrient status. Our findings implicate the genetic co-option events facilitating successful land plant establishment. The first land plant faced environmental challenges during terrestrial colonization. This study shows how the co-option of gene regulatory networks contributes to nutrient responses, facilitating the terrestrial adaptation of ancestral land plants.

mRNA translation relies on identifying translation initiation sites (TISs) in mRNAs. Alternative TISs are prevalent across plant transcriptomes, but the mechanisms for their recognition are unclear. Using ribosome profiling and machine learning, we developed models for predicting alternative TISs in the tomato (Solanum lycopersicum). Distinct feature sets were predictive of AUG and nonAUG TISs in 5 ' untranslated regions and coding sequences, including a novel CU-rich sequence that promoted plant TIS activity, a translational enhancer found across dicots and monocots, and humans and viruses. Our results elucidate the mechanistic and evolutionary basis of TIS recognition, whereby cis-regulatory RNA signatures affect start site selection. The TIS prediction model provides global estimates of TISs to discover neglected protein-coding genes across plant genomes. The prevalence of cis-regulatory signatures across plant species, humans, and viruses suggests their broad and critical roles in reprogramming the translational landscape.

Foliar pigmentation patterns vary among plant species and growth conditions. In this study, we utilize hyperspectral imaging to assess foliar pigmentation in the bryophyte Marchantia polymorpha under nutrient stress and identify associated genetic factors. Using singular value decomposition (SVD) for feature selection, we quantitate color variations induced by deficiencies in phosphate, nitrate, magnesium, calcium, and iron. Pseudo-colored thallus images show that disrupting MpWRKY10 causes irregular pigmentation with auronidin accumulation. Transcriptomic profiling shows that MpWRKY10 regulates phenylpropanoid pathway enzymes and R2R3-MYB transcription factors during phosphate deficiency, with MpMYB14 upregulation preceding pigment accumulation. MpWRKY10 is downregulated in older, pigmented thalli under phosphate deficiency but maintained in young thalli, where it suppresses pigmentation genes. This downregulation is absent in pigmented thalli due to aging. Comparative transcriptome analysis suggests similar WRKY and MYB roles in nutrient response and pigmentation in red-leaf lettuce, alluding to conserved genetic factors controlling foliar pigmentation patterns under nutrient deficiency.