Plant Physiology Research Articles

L-Theanine Metabolism in Tea Plants: Biological Functions and Stress Tolerance Mechanisms

L-theanine, a unique non-protein amino acid predominantly found in tea plants (Camellia sinensis), plays a pivotal role in plant responses to abiotic stress and significantly influences tea quality. In this review, the metabolism and transport mechanisms of L-theanine are comprehensively discussed, highlighting its spatial distribution in tea plants, where it is most abundant in young leaves and less so in roots, stems, and older leaves. The biosynthesis of L-theanine occurs through the enzymatic conversion of glutamate and ethylamine, catalyzed by theanine synthase, primarily in the roots, from where it is transported to aerial parts of the plant for further catabolism. Environmental factors such as temperature, light, drought, elevated CO2, nutrient unavailability, and heavy metals significantly affect theanine biosynthesis and hydrolysis, with plant hormones and transcription factors playing crucial regulatory roles. Furthermore, it has been demonstrated that applying L-theanine exogenously improves other crops’ resistance to a range of abiotic stresses, suggesting its potential utility in improving crop resilience amid climate change. This review aims to elucidate the physiological mechanisms and biological functions of L-theanine metabolism under stress conditions, providing a theoretical foundation for enhancing tea quality and stress resistance in tea cultivation.

Metabolites induced by citrus tristeza virus and ‘Candidatus Liberibacter asiaticus’ influence the feeding behavior of Diaphorina citri: an electrical penetration graph and LC–MS/MS study

Citrus Huanglongbing and Citrus tristeza are two diseases that affect the citrus industry worldwide. The pathogens causing these diseases are the phloem-limited bacteria ‘Candidatus Liberibacter spp.’ (mainly Ca. L. asiaticus, CLas) and citrus tristeza virus (CTV). We recently found that both CLas and CTV could be acquired and retained by the Asian citrus psyllid Diaphorina citri. However, the mechanism through which CLas and CTV interact with the insect vectors and plant hosts has not been defined. In this study, an electrical penetration graph was used to study the feeding behavior of D. citri adults on four groups of Citrus reticulata Blanco cv. Hongjü plants: healthy, CLas-infected, CTV-infected, and CTV-CLas coinfected plants. Liquid chromatography with tandem mass spectrometry (LC–MS/MS) was applied to analyze the metabolites of the four groups of plants. The combined results are as follows: (1) The lowest number of metabolites were enriched in CTV-infected plants, which hardly influenced the feeding behavior of D. citri, suggesting that mild CTV strain (CT31) infection caused limited disorders in citrus plants compared with CLas infection; (2) Increased levels of L-arabinose and kaempferol in CTV-infected and CLas-CTV coinfected plants were suggested to contribute to increased penetration time during feeding of D. citri. CLas-infection increases the difficulty of finding appropriate feeding sites by the vector and results in xylem feeding for certain duration; (3) A significant reduction in α-linolenic acid metabolism in CLas-infected plants was found to be related to methyl jasmonate signaling, which induced resistance to D. citri and increased the duration of salivation. This effect was reversed by coinfection with CTV and was consistent with the phloem structure and carbohydrate accumulation alteration; (4) Stress response-associated 2'-hydroxygenistein and sakuranetin were highly upregulated flavonoid in CTV-CLas coinfected plants. This combinged with the anatomical alterations might interfere with D. citri feeding in the citrus phloem, as reflected by the time reduction of sap-sucking there. These findings will provide new insights into the interactions between CTV and CLas in citrus and the insect vector D. citri that transmiting these pathogens.

Salicylic Acid Modulates Volatile Organic Compound Profiles During CEVd Infection in Tomato Plants

Background:Citrus Exocortis Viroid (CEVd) is a non-coding RNA pathogen capable of infecting a wide range of plant species, despite its lack of protein-coding ability. Viroid infections induce significant alterations in various physiological and biochemical processes, particularly impacting plant metabolism. This study shows the metabolic changes upon viroid infection in tomato plants (Solanum lycopersicum var. ‘MoneyMaker’) exhibiting altered levels of salicylic acid (SA), a key signal molecule involved in the plant defence against this pathogen. Methods: Transgenic RNAi_S5H lines, which have the salicylic acid 5-hydroxylase gene silenced to promote SA accumulation, and NahG lines, which overexpress a salicylate hydroxylase to degrade SA into catechol and prevent its accumulation, were used to establish different SA levels in plants, resulting in varying degrees of resistance to viroid infection. The analysis was performed by using gas chromatography–mass spectrometry (GC-MS) to explore the role of volatile organic compounds (VOCs) in plant immunity against this pathogen. Results: Our results revealed distinct volatile profiles associated with plant immunity, where RNAi_S5H-resistant plants showed significantly enhanced production of monoterpenoids upon viroid infection. Moreover, viroid-susceptible NahG plants emitted a broad range of VOCs, whilst viroid-tolerant RNAi_S5H plants exhibited less variation in VOC emission. Conclusions: This study demonstrates that SA levels significantly influence metabolic responses and immunity in tomato plants infected by CEVd. The identification of differential emitted VOCs upon CEVd infection could allow the development of biomarkers for disease or strategies for disease control.

IMPACT OF PATHOGENS ON THE GERMINATION AND INITIAL GROWTH OF WHEAT CULTIVARS: EVALUATION OF THE SEED DISINFESTATION METHOD

Wheat (Triticum aestivum L.) production faces challenges caused by abiotic and biotic factors, with diseases transmitted by contaminated seeds being a risk for pathogen-free areas. This study assessed the presence of pathogens in five wheat cultivars: Tbio Sinuelo, Tbio Toruk, ORS Madreperola, Tbio Ponteiro and LG Cromo. The “blotter test” method was used to assess the influence of these pathogens using the Hiltner test. The following variables were analyzed in seeds disinfected and not disinfected with 1% hypochlorite: germination (%), seed-to-seedling transmission, mean root length (MRL), mean shoot length (SPL), root fresh mass (RRM), root dry mass (RSM), shoot fresh mass (SPF) and shoot dry mass (SPD). The experiment, conducted at the Plant Physiology Laboratory of the Federal University of the Southern Frontier, followed a completely randomized design in a 5x2 factorial scheme. The sanitary analysis revealed the presence of the genera Fusarium, Aspergillus, Penicillium, Rhizopus and Alternaria. Although germination and seed-to-seedling transmission showed no significant difference between disinfected and non-disinfected seeds, there were statistical differences in the ARL, SPL, FRM, DRM, FRM and DSM components, with disinfected seeds showing higher averages.

Microclimates growing and watering volumes influences the physiological traits of chili pepper cultivars in combating abiotic stress.

Chili peppers are a staple food for countries worldwide and are loaded with vitamins and antioxidants. One of the world's largest chili consumers, Indonesia faces climate adversities and cash-crop pest infestations that affect its horticulture market. The present research explores microclimatic and watering for physiological performances in different chili cultivars, useful in suggesting the strategies of cultivation with a climate-resilient perception. The research was done in the Bale Tatanen, Padjadjaran University, using a Factorial Randomized Complete Block Design to analyze chili plant physiology. According to statistical analyses, cultivars did not significantly affect absolute growth rate (AGR), but growing microclimates and watering volumes did significantly affect AGR and water use efficiency (WUE). The rain shelter and screen house had the highest WUE and AGR values. Growing microclimates and cultivars significantly affected transpiration rate, stomatal conductance to water vapor and total conductance to CO2, with the screen house exhibiting the highest values. All three factors significantly affected the photosynthetic rate, with the greenhouse showing the highest rate. The photosynthetic photon flux density (PPFD) was likewise highest in the greenhouse. This study aimed to systematically assess these factors and it tried suggesting practices that might assist in combating the effects of abiotic stress on chili production, for its sustainability. The findings of this research would help in conceptualizing the most efficient microclimate and watering volume for chili cultivation particularly, when considering climate change challenges as well; these results could also be applied to develop guidelines which might serve helpful at resource-poor farming.

Microbial engineering for monocyclic aromatic compounds production.

Aromatic compounds, serve pivotal roles in plant physiology and exhibit antioxidative and antimicrobial properties, leading to their widespread application such as in food preservation and pharmaceuticals. However, direct plant extraction and petrochemical synthesis often struggles to meet current needs due to low yield or facing economic and environmental hurdles. In the past decades, systems metabolic engineering enabled eco-friendly production of various aromatic compounds, with some reached industrial levels. In this review, we highlight monocyclic aromatic chemicals, which have relatively simple structures and are currently the primary focus of microbial synthesis research. We then discuss systems metabolic engineering at the enzyme, pathway, cellular and bioprocess levels to improve the production of these chemicals. Finally, we overview the current limitations and potential resolution strategies, aiming to provide reference for future studies on the biosynthesis of aromatic products.

TGG1 and TGG2 mutations impair allyl isothiocyanate-mediated stomatal closure in Arabidopsis thaliana.

Myrosinase, referred to as thioglucoside glucohydrolase (TGG), plays a crucial role in plant physiology through catalyzing the hydrolysis of glucosinolates into bioactive isothiocyanates. In Arabidopsis thaliana, the myrosinases TGG1 and TGG2 are essential for abscisic acid- and methyl jasmonate-induced stomata closure. Allyl isothiocyanate (AITC), one of myrosinase products, triggers stomatal closure in A. thaliana. We investigated stomatal responses to AITC to clarify the role of TGG1 and TGG2 in Arabidopsis guard-cell signaling. Allyl isothiocyanate at 50μM and 100μM induced stomatal closure in the tgg1 and tgg2 single mutants but not in the tgg1 tgg2 double mutant. Furthermore, AITC at 50μM induced the production of reactive oxygen species and nitric oxide, cytosolic alkalization, and oscillations in cytosolic free calcium concentration in guard cells of both wild-type and mutant plants. These findings suggest that TGG1 and TGG2 are involved in AITC signaling pathway through interaction with signal component(s) downstream of these signaling events, which is not accompanied by hydrolysis of glucosinolates because of the difference in subcellular localization between enzymes (myrosinases) and substrates (glucosinolates).

HTD: a targetome database for plant physiology and regulation in HPPD family.

HTD: a targetome database for plant physiology and regulation in HPPD family.

Metabolome profiling dissects the oat (Avena sativa L.) innate immune response to Pseudomonas syringae pathovars.

One of the most important characteristics of successful plant defence is the ability to rapidly identify potential threats in the surrounding environment. Plants rely on the perception of microbe-derived molecular pattern chemicals for this recognition, which initiates a number of induced defence reactions that ultimately increase plant resistance. The metabolome acts as a metabolic fingerprint of the biochemical activities of a biological system under particular conditions, and therefore provides a functional readout of the cellular mechanisms involved. Untargeted metabolomics was applied to decipher the biochemical processes related to defence responses of oat plants inoculated with pathovars of Pseudomonas syringae (pathogenic and non-pathogenic on oat) and thereby identify signatory markers that are involved in host or nonhost defence responses. The strains were P. syringae pv. coronafaciens (Ps-c), P. syringae pv. tabaci, P. syringae pv. tomato DC3000 and the hrcC mutant of DC3000. At the seedling growth stage, metabolic alterations in the Dunnart oat cultivar (tolerant to Ps-c) in response to inoculation with the respective P. syringae pathovars were examined following perception and response assays. Following inoculation, plants were monitored for symptom development and harvested at 2-, 4- and 6 d.p.i. Methanolic leaf extracts were analysed by ultra-high-performance liquid chromatography (UHPLC) connected to high-definition mass spectrometry. Chemometric modelling and multivariate statistical analysis indicated time-related metabolic reconfigurations that point to host and nonhost interactions in response to bacterial inoculation/infection. Metabolic profiles derived from further multivariate data analyses revealed a range of metabolite classes involved in the respective defence responses, including fatty acids, amino acids, phenolic acids and phenolic amides, flavonoids, saponins, and alkaloids. The findings in this study allowed the elucidation of metabolic changes involved in oat defence responses to a range of pathovars of P. syringae and ultimately contribute to a more comprehensive view of the oat plant metabolism under biotic stress during host vs nonhost interactions.

Soil data from the Barbastro-Balaguer gypsum belt, NE Spain.

The dataset [1] hosts pedological info and images of the lands -locally known as chesas- of the outcropping gypsiferous core of the Barbastro-Balaguer anticline (Fig. 1). It stands out in the landscape for the linear reliefs due to outcrops of dipping strata with differential resistance to erosion, and also because of its whitish color (Fig. 2) and gypsophilous vegetation. This gypsum outcrop was named in the 19th Century [2] as a gypseous belt, and has been further studied by other geologists like [3,4] and by civil engineers e.g. Hué and Llamas [5]. Traditionally chesas were rangeland, with sparse almond and olive trees and rainfed winter cereals confined at the flat -and often terraced- valley bottoms, or vales as known in NE Spain. The chesas have attracted the attention of botanists [[6], [7], [8]], foresters [9,10], and soil hydrophysical properties researchers [11]. Moreover, public interest is increasing as the administrations are establishing rules for nature protection in the gypseous lands, e.g., a demarcation of 137 km2 set within the chesas was declared a Special Conservation Area "ES2410074 Yesos de Barbastro", and then protected by the Habitats Directive of European Union. Also, plant physiologists are focusing on the adaptations of plants to gypsum as reviewed by Escudero et al. [12]. No soil map is available, but according to [13,14] the Gypsic Haploxerepts [15] are dominant. In the absence of a soil map, our dataset can help in the decisions to be made by the authorities, as is the case for water allocation to irrigated estates both in operation and planned, or for authorizations for the spreading of pig slurry. The herein presented soil data were collected with the classical techniques of pedological prospection. The dataset [1] contains the scans in .TIFF format of 150 whole thin sections of the soils, under both plane polarized light (PPL) and cross polarized light (XPL). Moreover, this dataset directs to a freely downloadable book [16] with the corresponding pedological descriptions, chemical and physical analyses, hydrophysical data, and scanning electron microscope images of the soils, plus micrographs of relevant pedofeatures of thin sections seen under petrographic microscope. The dataset [1] also presents a .xlsx file with an English translation of all figure captions of [16], including those of micrographs, and two more .xlsx files with analytical data. All data can be reused directly by naturalists, engineers, technicians and public servants in charge of environmental law development and enforcement, as well as by people involved in citizen science activities. Thin sections remain stored at EEAD and can be examined at our premises upon request.

Accumulation, translocation and transformation of artificial sweeteners in plants: A critical review.

Artificial sweeteners (ASs) have become an increasingly significant concern as an emerging contaminant. The widespread utilization has given rise to environmental consequences that are progressively harder to disregard. ASs infiltrate both aquatic and terrestrial ecosystems through the discharge of wastewater effluents and the application of manure and biosolids. These compounds can be absorbed and accumulated by plants from soil, water and the atmosphere, posing potential risks to ecological systems and human health. However, limited data available on plant absorption, translocation, and metabolism of ASs hinders a comprehensive understanding of their impact on ecosystem. This study aims to comprehensively summarize the global distribution of ASs, along with elucidating patterns of their uptake and accumulation within plants. Furthermore, it seeks to elucidate the pivotal factors governing ASs absorption and translocation, encompassing hydrophilicity, ionic nature, plant physiology, and environmental conditions. Notably, there remains a significant knowledge gap in understanding the biodegradation of ASs within plants, with their specific degradation pathways and mechanisms largely unexplored, thereby necessitating further investigation. Additionally, this review provides valuable insights into the ecotoxicological effects of ASs on plants. Finally, it identifies research gaps and outlines potential avenues for future research, offering a forward-looking perspective on this critical issue.

Beyond red and blue: Unveiling the hidden action of green wavelengths on plant physiology, metabolisms and gene regulation in horticultural crops

Beyond red and blue: Unveiling the hidden action of green wavelengths on plant physiology, metabolisms and gene regulation in horticultural crops

The role of nitric oxide and nitrogen in mediating copper stress in Brassica juncea L.

Copper (Cu) holds a significant importance in plant metabolism as it serves as an essential micronutrient but becomes toxic at higher concentrations. Nitric oxide (NO), a key signaling molecule, and nitrogen (N) play essential roles in combating toxicity of some metals. This study explores the potential of interactive effects of NO as 100µM SNP (sodium nitroprusside, NO source) and N (80mgN kg-1 soil) in mitigating Cu (100mg Cu kg-1 soil) stress in mustard (Brassica juncea L.) plants. The impaired physio-biochemical changes, photosynthetic efficiency, and the expression level of genes associated with photosynthesis, and N assimilation under Cu stress were ameliorated with the exogenous application of NO and N. The combined treatment of NO and N conspicuously lowered reactive oxygen species (ROS) and its related impacts. It also enhanced the activity and relative expression of antioxidant enzymes, including ascorbate peroxidase (APX), glutathione reductase (GR), and superoxide dismutase (SOD) as well as N assimilation enzymes, such as nitrate reductase (NR) and nitrite reductase (NiR). The supplementation of NO and N also triggered the expression of rbcL (large subunit of Rubisco), photosystem (photosystem II D1 protein; psbA and photosystem II protein B; psbB) and markedly improved photosynthetic capacity under Cu stress. The study highlights the significance of NO and N as a potential strategy to counteract Cu-induced stress in crops. It suggests a synergistic or interactive effect between the two substances as a phytoremediation strategy for enhancing crop growth and productivity in Cu-contaminated soils. Understanding the mechanisms behind NO and N mediated stress alleviation could facilitate the development of targeted approaches to enhance plant resilience against heavy metal stress.

Transcriptome datasets of salt-stressed tomato plants treated with zinc oxide nanoparticles.

Salinity diminishes agricultural productivity and quality, resulting in overall economic losses on a worldwide scale. Zinc oxide nanoparticles (ZnO-NPs) have been found to enhance plant physiological and metabolic processes, as well as increase overall resilience to abiotic stressors. A research study was undertaken to assess the effects of foliar application of chemically produced ZnO-NPs on tomato plants, both in the presence and absence of a NaCl stressor. The datasets were obtained through the utilization of the shallow mRNA sequencing technology. Six datasets from the SRA were uploaded to NCBI. The aforementioned datasets encompass the Transcriptome Shotgun Assembly (TSA), the contigs that underwent blasting, mapping, and annotation from the pre-processed datasets, and the count table derived from the quantification of RNA-seq reads. All the aforementioned data is encompassed under the Mendeley database. Moving forward, the utilization of databases will facilitate the examination of modifications in plant biochemical reactions at the level of gene expression.

Possible role of autophagy in microbial volatile pollutant-induced starch degradation and expression of hypoxia responsive genes.

Autophagy is thought to be critically involved in the regulation of nutrient metabolism and gene expression. Nevertheless, little is known about its role in regulating starch metabolism and hypoxia responsive genes in plants exposed to microbial volatile pollutants. In the present study, we found that exposure of Arabidopsis to Enterobacter aerogene (E. aerogene) volatile pollutants induced autophagy, as indicated by autophagosome formation. The exposure also caused upregulation of autophagy-associated genes, such as ATGs, NBR1, ATI1, and ATG8e-regulating transcription factors. Additionally, exposure to E. aerogenes volatile pollutants induced starch degradation in the roots of Arabidopsis seedlings. Finally, we found that ATG7-deficiency negatively affected the expression of hypoxia-responsive genes (i.e HRE1, HRA1, and ADH1) and starch degradation induced by E. aerogenes volatile pollutants. Overall, our study reveals that microbial volatile pollutants can induce starch degradation and autophagy, which participates in the regulation of some hypoxia-responsive genes and starch metabolism. These findings help to define the role of autophagy in plant nutrient metabolism and regulation of gene expression under microbial volatile pollutant exposure. The insights gained may contribute to agricultural management when living organisms face challenges from microbial volatile pollutants.

Alternative transcriptional initiation of OsβCA1 produces three distinct subcellular localization isoforms involved in stomatal response regulation and photosynthesis in rice.

Plants adjust the size of their stomatal openings to balance CO2 intake and water loss. Carbonic anhydrases (CAs) facilitate the conversion between CO2 and HCO3 -, and theOsβCA1 mutant in rice (Oryza sativa) shows similar traits in carbon fixation and stomatal response to CO2 as the dual βCA mutants in Arabidopsis thaliana. However, the exact role of OsβCA1 in these processes was unclear. We used gene editing, molecular biology, and plant physiology to study how OsβCA1 contributes to carbon fixation, stomatal opening, and CO2 responses. OsβCA1 produces three isoforms (OsβCA1A, OsβCA1B, and OsβCA1C) through alternative transcriptional initiation, which localize to the chloroplast, cell membrane, and cytosol, respectively. Protein measurements revealed that OsβCA1A/C and OsβCA1B contribute 97 and 3% to OsβCA1, respectively. By creating specific mutants for each isoform, our results found that the chloroplast and cell membrane isoforms independently participate in carbon fixation and regulation of stomatal aperture. Furthermore, the complete knockout of OsβCA1 caused a delayed response to low CO2. Our findings provide new insights into the generation and function of different OsβCA1 isoforms, clarifying their roles in CO2 diffusion, CO2 fixation and stomatal regulation in rice.

Short-term airborne ultrasound induced cell death in tobacco cells and changed their wall components

The effects of low-intensity ultrasound on plants such as piezoelectric and ultrasonic water baths, on plants have been extensively studied. However, the specific effect of airborne ultrasound on plant cells has yet to be reported. The present study was conducted to elucidate the physiological responses of plant cells to airborne US. Homogeneous suspension-cultured tobacco cells (Nicotiana tabacum L. cv Burley 21) were subjected to airborne US at 24 kHz in two pulsatile and continuous modes for 10 and 20 s. The study’s outcome revealed that airborne US triggered the production of H2O2, elevated internal calcium concentration, and reduced antioxidant capacity upon cavitation. Alteration of covalently bound peroxidase and other wall-modifying enzyme activities was accompanied by reduced cellulose, pectin, and hemicellulose B but increased lignin and hemicellulose A. The biomass and viability of tobacco cells were also significantly decreased by airborne US, which ultimately resulting in PCD and secondary necrosis. The results highlight the potential risks of even short-time exposure to the airborne US on plant physiology and cell wall chemical composition raising significant concerns about its implications.

Harnessing Spectral Libraries From AVIRIS-NG Data for Precise PFT Classification: A Deep Learning Approach.

The generation of spectral libraries using hyperspectral data allows for the capture of detailed spectral signatures, uncovering subtle variations in plant physiology, biochemistry, and growth stages, marking a significant advancement over traditional land cover classification methods. These spectral libraries enable improved forest classification accuracy and more precise differentiation of plant species and plant functional types (PFTs), thereby establishing hyperspectral sensing as a critical tool for PFT classification. This study aims to advance the classification and monitoring of PFTs in Shoolpaneshwar wildlife sanctuary, Gujarat, India using Airborne Visible/Infrared Imaging Spectrometer-Next Generation (AVIRIS-NG) and machine learning techniques. A comprehensive spectral library was developed, encompassing data from 130 plant species, with a focus on their spectral features to support precise PFT classification. The spectral data were collected using AVIRIS-NG hyperspectral imaging and ASD Handheld Spectroradiometer, capturing a wide range of wavelengths (400-1600 nm) to encompass the key physiological and biochemical traits of the plants. Plant species were grouped into five distinct PFTs using Fuzzy C-means clustering. Key spectral features, including band reflectance, vegetation indices, and derivative/continuum properties, were identified through a combination of ISODATA clustering and Jeffries-Matusita (JM) distance analysis, enabling effective feature selection for classification. To assess the utility of the spectral library, three advanced machine learning classifiers-Parzen Window (PW), Gradient Boosted Machine (GBM), and Stochastic Gradient Descent (SGD)-were rigorously evaluated. The GBM classifier achieved the highest accuracy, with an overall accuracy (OAA) of 0.94 and a Kappa coefficient of 0.93 across five PFTs.

Hidden hunger: from a plant biologist's perspective.

In recent years, changes in dietary patterns from an omnivore diet to a moderate-to-restrictive diet that includes more plant food are becoming popular for various reasons and the associated health benefits. Despite the increased consumption of plant food as recommended by these seemingly healthy diets, micronutrient deficiency is still prevalent particularly among the health-conscious populations. The aim of this review is to help guide interventions by understanding micronutrient deficiency trends from a dietary habit and plant physiology context. In this review, the author discusses how modern agricultural practices coupled with climate change, and with particular emphasis on the extreme dietary habits that lack variation and excessive consumption, may contribute to an increased ingestion of antinutrients which in turn potentially exacerbate vitamin and mineral deficiencies. While plants possess a wide range of secondary metabolites that exert beneficial health effects, some of these compounds are also antinutrients that interfere with the digestion and absorption of nutrients and micronutrients. Furthermore, the article also raises questions concerning the fate of antinutrient traits in future crops that were to be redesigned with improved stress tolerance, and the impacts it may have on human nutrition and the environment. © 2025 Society of Chemical Industry.

Nitro-fatty acids modulate germination onset through S-nitrosothiol metabolism.

-Nitro-fatty acids (NO2-FAs) have emerged as key components of nitric oxide (NO) signalling in eukaryotes. We previously described how nitro-linolenic acid (NO2-Ln), the major NO2-FA detected in plants, regulates S-nitrosoglutathione (GSNO) levels in Arabidopsis (Arabidopsis thaliana). However, the underlying molecular mechanisms remain undefined. Here, we used a combination of physiological, biochemical, and molecular approaches to provide evidence that NO2-Ln modulates S-nitrosothiol (SNO) content through S-nitrosylation of S-nitrosoglutathione reductase1 (GSNOR1) and its impact on germination onset. The aer mutant (a knockout mutant of the alkenal reductase enzyme; AER) exhibits higher NO2-Ln content and lower GSNOR1 transcript levels, reflected by higher SNO content and S-nitrosylated proteins. Given its capacity to release NO, NO2-Ln mediates the S-nitrosylation of GSNOR1, demonstrating that NO2-FAs can indirectly modulate total SNO content in plants. Moreover, the ectopic application of NO2-Ln to dormant seeds enhances germination success similarly to the aer germination rate, which is mediated by the degradation of master regulator ABSCISIC ACID INSENSITIVE 5 (ABI5). Our results establish that NO2-FAs regulate plant development through NO and SNO metabolism and reveal a role of NO2-FAs in plant physiology.