Signaling Molecule In Plants Research Articles

Atmospheric cold plasma alters plant traits and negatively affects the growth and development of fall armyworm in rice

Plasma is considered as the fourth state of matter, and atmospheric cold plasma (cold plasma) is a type of plasma consisting of ionized gases containing excited species of atoms, molecules, ions, and free radicals at near room temperature. Cold plasma is generated by applying high voltage to gases, causing it to ionize thus forming plasma. Although cold plasma has been found to break seed dormancy and improve germination rate, only a few studies have explored the potential of cold plasma against insect herbivory. Given that cold plasma produces reactive oxygen and nitrogen species that can activate plant signalling molecules, it is plausible that cold plasma can have differential effects against insect herbivores. To test this, we evaluated the effectiveness of cold plasma on a polyphagous lepidopteran pest, Fall armyworm (FAW) [Spodoptera frugiperda (Lepidoptera: Noctuidae)] on rice (Oryza sativa L.) using an atmospheric plasma jet reactor that generated cold plasma using ambient air as the source gas. We treated rice seeds from two commonly grown Arkansas cultivars (Jewel and Diamond) with cold plasma, followed by irrigation with Cold Plasma-Activated Water (PAW). We then independently tested FAW growth on an artificial diet partially made with PAW. Our results show that cold plasma significantly affected the feeding, growth, and development of FAW, irrespective of the rice varieties. The effects of cold plasma treatment resulted in reduced damage by FAW, lower mass gain and longer pupation period on FAW compared to the untreated control. However, the effects of cold plasma on rice growth and development were dependent on the rice varieties. Cold plasma treatment also induced detrimental effects on FAW leading to ~ 25% mortality on cold plasma-treated plants when compared to untreated controls. Collectively, these findings offer significant evidence of the potential of cold plasma as a novel component for sustainable pest management.

Monitoring CO as a plant signaling molecule under heavy metal stress using carbon nanodots.

Carbon monoxide (CO) is widely recognized as a significant environmental pollutant and is associated with numerous instances of accidental poisoning in humans. However, it also serves a pivotal role as a signaling molecule in plants, exhibiting functions analogous to those of other gaseous signaling molecules, including nitric oxide (NO) and hydrogen sulfide (H2S). In plant physiology, CO is synthesized as an integral component of the defense mechanism against oxidative damage, particularly under abiotic stress conditions such as drought, salinity, and exposure to heavy metals. Current research methodologies have demonstrated a lack of effective tools for monitoring CO dynamics in plants during stress conditions, particularly in relation to heavy metal accumulation across various developmental stages. Therefore, development of a sensor capable of detecting CO in living plant tissues is essential, as it would enable a deeper understanding of its biological functions, underlying mechanisms, and metabolic pathways. In response to this gap, the present study introduces a novel technique for monitoring CO production and activity in plants using nitrogen-doped carbon quantum dots (N-CQDs). These nanodots exhibited exceptional biocompatibility, low toxicity, and environmentally sustainable characteristics, rendering them an optimal tool for CO detection via fluorescence quenching mechanism, with a detection limit (LOD) of 0.102 μM. This innovative nanomarker facilitated the detection of trace quantities of CO within plant cells, providing new insights into plant stress responses to heavy metals such as Cu, Zn, Pb, Ru, Cr, Cd, and Hg, as well as the processes involved in seed germination. Additionally, confocal microscopy validated the interaction between CO and N-CQDs, yielding visual evidence of CO binding within plant cells, further enhancing the understanding of CO's role in plant biology.

Synergist effects of some PGPR bacteria and sodium nitroprusside in pepper plant

Plant growth promoting rhizobacteria (PGPR) represent promotes plant growth by increasing the supply or availability of nutrients to the host plant. These bacterial applications are environmentally friendly techniques and their use has become widespread recently. Some PGPRs can increase nitrogen (N) fixation and have phosphate (P) solubilizing property. In the current study, we evaluated the synergistic effects of some useful bacteria and sodium nitroprusside (SNP, a nitric oxide donor) in pepper plant. Nitric oxide (NO) acts as a signal molecule in plants and has important role in plant-bacteria symbiosis interaction. Three PGPR strains namely, Enterobacter cloacae (ZE-2), Pseudomonas putida (ZE-12) and Acinetobacter calcoaceticus (ZE-13) were used and the bacteria possess phosphorous-solubilizing and nitrogen-fixing properties. The applications of PGPRs alone and with combination of SNP (0.1 mM) were performed to the plant rhizosphere (the roots) through irrigation two times with two weeks interval starting with seedling planting. End of the study, many morphological parameters including stem diameter, plant height and biomass were improved by all applications compared to control. Root:shoot dry weight ratio decreased by the applications. Stem diameter, plant height and biomass were significantly increased with all treatments compared to control. The yield was found higher in all applications compared to control and the highest increase in the yield was provided by Enterobacter cloacae (ZE-2) application. Dry matter allocation in upper part of the plants provided higher plant yield. The applications significantly affected cell expansion and division. SNP increased the effect of Acinetobacter calcoaceticus (ZE-13) bacteria on cell division in leaf cells and midrib size. Furthermore, Pseudomonas putida (ZE-12) increased the yield combining with SNP compared to alone use. The increase in the plant growth is related with the midrib size. The application of PGPR with SNP could be a promising approach in plant growing.

Differential microRNA and Target Gene Expression in Scots Pine (Pinus sylvestris L.) Needles in Response to Methyl Jasmonate Treatment.

Background/objectives: Methyl jasmonate is a plant signaling molecule involved in a wide range of functions, including stress responses. This study investigates the relative differential expression of microRNAs and their target genes in response to methyl jasmonate treatment of Scots pine needles. Methods: A combined strategy of high-throughput sequencing and in silico prediction of potential target genes was implemented. Results: a total of 58 differentially expressed (DE) microRNAs (miRNAs) (43 up-regulated and 15 down-regulated), belonging to 29 miRNA families, were identified. The 41 DE miRNAs from 17 families were conifer-specific miRNA families-miR946, miR947, miR950, miR1312, miR1313, miR1314, miR3693, miR3107, miR11452, miR11466, miR11487, miR11490, miR11504, miR11511, miR11532, miR11544, and miR11551. The other DE miRNAs (miR159, miR164, miR169, miR396, miR397, miR398, miR408, miR535) were conserved miRNAs, which are also found in angiosperm species. Transcriptome analysis identified 389 gene transcripts with 562 miRNA-target sites targeted by 57 of the 58 DE miRNAs. Of these, 250 target genes with 138 different GO annotations were found for the 41 DE conifer-specific conserved miRNAs. Conclusions: The 26 DE miRNAs from 14 DE miRNA families, of which almost all (12 families, 24 miRNAs) are conifer specific, and were associated with 68 disease resistance and TMV resistance proteins, TIR-NBS-LRR, LRR receptor-like serine/threonine-protein kinase, putative CC-NBS-LRR protein, and putative NBS-LRR protein target transcripts with 29 target gene GO term descriptions. Some of the genes targeted by conifer-specific miRNAs have been previously reported to be targeted by other miRNAs in angiosperms, indicating that the miRNA-target gene regulation system can vary between species.

Improving Soybean Germination and Nodule Development with Nitric Oxide-Releasing Polymeric Nanoparticles

Nitric oxide (NO) is a multifunctional signaling molecule in plants, playing key roles in germination, microbial symbiosis, and nodule formation. However, its instability requires innovative approaches, such as using nanoencapsulated NO donors, to prolong its effects. This study evaluated the impact of treating soybean (Glycine max) seeds with the NO donor S-nitrosoglutathione (GSNO), encapsulated in polymeric nanoparticles, on the germination, nodulation, and plant growth. Seeds were treated with free GSNO, chitosan nanoparticles with/without NO (NP CS-GSNO/NP CS-GSH, where GSH is glutathione, the NO donor precursor), and alginate nanoparticles with/without NO (NP Al-GSNO/NP Al-GSH). Chitosan nanoparticles (positive zeta potential) were smaller and released NO faster compared with alginate nanoparticles (negative zeta potential). The seed treatment with NP CS-GSNO (1 mM, related to GSNO concentration) significantly improved germination percentage, root length, number of secondary roots, and dry root mass of soybean compared with the control. Conversely, NP CS-GSH resulted in decreased root and shoot length. NP Al-GSNO enhanced shoot dry mass and increased the number of secondary roots by approximately threefold at the highest concentrations. NP CS-GSNO, NP Al-GSNO, and NP Al-GSH increased S-nitrosothiol levels in the roots by approximately fourfold compared with the control. However, NP CS-GSNO was the only treatment that increased the nodule dry mass of soybean plants. Therefore, our results indicate the potential of chitosan nanoparticles to improve the application of NO donors in soybean seeds.

Molecular evolution and interaction of ROS with ion transport for plant abiotic stresses

AbstractReactive oxygen species (ROS) serve as crucial signaling molecules in plants, enabling rapid responses to environmental stresses such as abiotic factors. ROS production primarily stems from the activation of enzymes such as nicotinamide adenine dinucleotide phosphate (NADPH) oxidases and peroxidases, as well as disruptions in the respiratory and photosynthetic electron transport chains. This oxidative stress triggers signaling pathways that involve in calcium ion (Ca2+) influx across cell membranes, altering ionic conductance. ROS encompass hydroxyl radicals (OH•) and hydrogen peroxide (H2O2), which activate hyperpolarization‐activated Ca2+ channels and influence ion transport dynamics. Our review focuses on the mechanisms driving ROS generation and ion transport during plant responses to abiotic stress. We explore the regulation, characteristics, and potential structures of ROS‐activated ion channels in plants. Specifically, we examine the molecular responses and evolutionary adaptations of Shaker‐type K+ channels (AKT/KAT/GORK/SKOR) under stress conditions. Comparative genetic analyses highlight the conservation of these channels and other ROS‐regulated proteins (e.g., MDHAR, POX, and RBOH), suggesting their essential roles in plant to adapt to diverse stresses. This study underscores the significance of ROS‐regulated proteins in plant stress responses, advocating for further research to elucidate their fundamental roles.

Polyamines: The valuable bio-stimulants and endogenous signaling molecules for plant development and stress response.

Polyamines (PAs) are nitrogenous and polycationic compounds containing more than two amine residues. Numerous investigations have demonstrated that cellular PA homeostasis plays a key role in various developmental and physiological processes. The PA balance, which may be affected by many environmental factors, is finely maintained by the pathways of PA biosynthesis and degradation (catabolism). In this review, the advances in PA transport and distribution and their roles in plants were summarized and discussed. In addition, the interplay between PAs and phytohormones, NO, and H2O2 were detailed during plant growth, senescence, fruit repining, as well as response to biotic and abiotic stresses. Moreover, it was elucidated how environmental signals such as light, temperature, and humidity modulate PA accumulation during plant development. Notably, PA has been shown to exert a potential role in shaping the domestication of rice. The present review comprehensively summarizes these latest advances, highlighting the importance of PAs as endogenous signaling molecules in plants, and as well proposes future perspectives on PA research.

Genome-Wide Identification of the RALF Gene Family and Expression Pattern Analysis in Zea mays (L.) under Abiotic Stresses.

Rapid Alkalization Factor (RALF) is a signaling molecule in plants that plays a crucial role in growth and development, reproductive processes, and responses to both biotic and abiotic stresses. Although RALF peptides have been characterized in Arabidopsis and rice, a comprehensive bioinformatics analysis of the ZmRALF gene family in maize is still lacking. In this study, we identified 20 RALF genes in the maize genome. Sequence alignment revealed significant structural variation among the ZmRALF family genes. Phylogenetic analysis indicates that RALF proteins from Arabidopsis, rice, and maize can be classified into four distinct clades. Duplication events suggest that the expansion of the RALF gene family in maize primarily relies on whole-genome duplication. ZmRALF genes are widely expressed across various tissues; ZmRALF1/15/18/19 are highly expressed in roots, while ZmRALF6/11/14/16 are predominantly expressed in anthers. RNA-seq and RT-qPCR demonstrated that the expression levels of ZmRALF7, ZmRALF9, and ZmRALF13 were significantly up-regulated and down-regulated in response to PEG and NaCl stresses, respectively. Overall, our study provides new insights into the role of the RALF gene family in abiotic stress.

The Different Concentrations of Applied Exogenous Sugars Widely Influence the Specificity, Significance and Physiological Relevance of Study Outcomings.

Plant growth and development are governed via signal networks that connect inputs from nutrient status, hormone signals, and environmental cues. Substantial researches have indicated a pivotal role of sugars as signalling molecules in plants that integrate external environmental cues and other nutrients with intrinsic developmental programmes regulated via multiple plant hormones. Therefore, plant growth and development are controlled through complication signalling networks. However, in many studies, to obtain more obviously experimental findings, excess concentrations of applied exogenous sugars have aggravated the complexity of this signalling networks. Once researchers underestimate this complexity, a series of contradictory or contrasting findings will be generated. More importantly, in terms of these contradictory findings, more contradictory study outcomings are derived. In this review, we carefully analyze some reports, and find that these reports have confused or neglected that the sugar-antagonism of ethylene signalling is specific or conditional. As a result, many contradictory conclusions are generated, which will in turn misdirect the scientific community.

Elucidating the downstream pathways triggered by H2S signaling in Arabidopsis thaliana under drought stress via transcriptome analysis

ABSTRACT Hydrogen sulfide (H2S) is a crucial signaling molecule in plants. Recent studies have shown that H2S plays an equally important role as nitric oxide (NO) and hydrogen peroxide (H2O2) in plant signaling. Previous studies have demonstrated the involvement of H2S in regulating drought and other stressful environmental conditions, but the exact downstream molecular mechanisms activated by the H2S signaling molecule remain unclear. In this study, we conducted a comprehensive genome-wide transcriptomic analysis of both wild type (WT) and double mutant (lcd/des1). Arabidopsis thaliana plants were exposed to 40% polyethylene glycol (PEG) to induce drought stress and 20 µM sodium hydrosulfide (NaHS). The resulting transcriptome data were analyzed for differentially significant genes and their statistical enrichments in the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. The results indicated significant upregulation of genes related to photosynthesis, carbon fixation, plant secondary metabolite biosynthesis, inositol and phosphatidylinositol signaling pathways, and stress-responsive pathways in mutant plants under drought stress. Mutant plants with impaired H2S signaling mechanisms displayed greater susceptibility to drought stress compared to wild-type plants. In summary, all findings highlight the pivotal role of H2S signaling in stimulating other drought-responsive signaling pathways.

Nucleotides and nucleotide derivatives as signal molecules in plants.

In reaction to a stimulus, signaling molecules are made, generate a response, and are then degraded. Nucleotides are classically associated with central metabolism and nucleic acid biosynthesis, but there are a number of nucleotides and nucleotide derivatives in plants to which this simple definition of a signaling molecule applies in whole or at least in part. These include cytokinins and chloroplast guanosine tetraposphate (ppGpp), as well as extracellular canonical nucleotides such as extracellular ATP (eATP) and NAD+ (eNAD+). In addition, there is a whole series of compounds derived from NAD+ such as ADP ribose (ADPR), and ATP-ADPR dinucleotides and their hydrolysis products (e.g. pRib-AMP) together with different variants of cyclic ADPR (cADPR, 2´-cADPR, 3´-cADPR), and also cyclic nucleotides such as 3´,5´-cAMP and 2´,3´-cyclic nucleoside monophosphates. Interestingly, some of these compounds have recently been shown to play a central role in pathogen defense. In this review, we highlight these exciting new developments. We also review nucleotide derivatives that are considered as candidates for signaling molecules, for example purine deoxynucleosides, and discuss more controversial cases.

Interorgan, intraorgan and interplant communication mediated by nitric oxide and related species.

Plant survival to a potential plethora of diverse environmental insults is underpinned by coordinated communication amongst organs to help shape effective responses to these environmental challenges at the whole plant level. This interorgan communication is supported by a complex signal network that regulates growth, development and environmental responses. Nitric oxide (NO) has emerged as a key signalling molecule in plants. However, its potential role in interorgan communication has only recently started to come into view. Direct and indirect evidence has emerged supporting that NO and related species (S-nitrosoglutathione, nitro-linolenic acid) are mobile interorgan signals transmitting responses to stresses such as hypoxia and heat. Beyond their role as mobile signals, NO and related species are involved in mediating xylem development, thus contributing to efficient root-shoot communication. Moreover, NO and related species are regulators in intraorgan systemic defence responses aiming an effective, coordinated defence against pathogens. Beyond its in planta signalling role, NO and related species may act as ex planta signals coordinating external leaf-to-leaf, root-to-leaf but also plant-to-plant communication. Here, we discuss these exciting developments and emphasise how their manipulation may provide novel strategies for crop improvement.

OsCYP706C2 diverts rice strigolactone biosynthesis to a noncanonical pathway branch.

Strigolactones exhibit dual functionality as regulators of plant architecture and signaling molecules in the rhizosphere. The important model crop rice exudes a blend of different strigolactones from its roots. Here, we identify the inaugural noncanonical strigolactone, 4-oxo-methyl carlactonoate (4-oxo-MeCLA), in rice root exudate. Comprehensive, cross-species coexpression analysis allowed us to identify a cytochrome P450, OsCYP706C2, and two methyl transferases as candidate enzymes for this noncanonical rice strigolactone biosynthetic pathway. Heterologous expression in yeast and Nicotiana benthamiana indeed demonstrated the role of these enzymes in the biosynthesis of 4-oxo-MeCLA, which, expectedly, is derived from carlactone as substrate. The oscyp706c2 mutants do not exhibit a tillering phenotype but do have delayed mycorrhizal colonization and altered root phenotype. This work sheds light onto the intricate complexity of strigolactone biosynthesis in rice and delineates its role in symbiosis and development.

Understanding pyrethrin biosynthesis: toward and beyond natural pesticide overproduction.

Pyrethrins are natural insecticides biosynthesised by Asteraceae plants, such as Tanacetum cinerariifolium and have a long history, dating back to ancient times. Pyrethrins are often used as low-persistence and safe insecticides to control household, horticultural, and agricultural insect pests. Despite its long history of use, pyrethrin biosynthesis remains a mystery, presenting a significant opportunity to improve yields and meet the growing demand for organic agriculture. To achieve this, both genetic modification and non-genetic methods, such as chemical activation and priming, are indispensable. Plants use pyrethrins as a defence against herbivores, but pyrethrin biosynthesis pathways are shared with plant hormones and signal molecules. Hence, the insight that pyrethrins may play broader roles than those traditionally expected is invaluable to advance the basic and applied sciences of pyrethrins.

A review on the application of advanced soil and plant sensors in the agriculture sector

Sensors implemented in agriculture play a significant role in soil and plant growth and enable real-time physical and chemical interactions in the environment, such as temperature, moisture/humidity, pH, and contaminant levels. Additionally, these sensors provide essential data that can enhance crop growth scenarios, resist biotic and abiotic stresses, and improve crop production. This article provides a thorough examination of the evolving landscape of agricultural sensor technologies, perspectives, and challenges in the field. Currently, some of the key soil sensors used in agricultural programs, include those that measure moisture, temperatures, pH, organic matter components, insects, and soil pollutants. On the other hand, nanobiotechnology sensors implement optical, wireless, or electrical signals to provide information about plant signaling molecules related to the conditions of agronomic equipment. We shed more light on the use of nanomaterial-facilitated transport of genetically encoded sensors as devices for the investigation and advancement of advanced plant sensors. Innovative technologies, including wireless sensor networks and plant wearables, are also addressed with regard to their potential for precision agriculture. The paper concludes by presenting future perspectives and difficulties in the fields of soil sensors and intelligent agriculture. In summary, we provide a comprehensive and forward-looking perspective on the potential of nanotechnology to facilitate the development of intelligent plant sensors. These sensors are capable of communicating with and controlling electrical equipment, with the aim of tracking and improving the output and resources applied to individual plants.

Exogenous melatonin alleviates sodium chloride stress and increases vegetative growth in Lonicera japonica seedlings via gene regulation

Melatonin (Mt) functions as a growth regulator and multifunctional signaling molecule in plants, thereby playing a crucial role in promoting growth and orchestrating protective responses to various abiotic stresses. However, the mechanism whereby exogenous Mt protects Lonicera japonica Thunb. (L. japonica) against salt stress has not been fully elucidated. Therefore, this study aimed to elucidate how exogenous Mt alleviates sodium chloride (NaCl) stress in L. japonica seedlings. Salt-sensitive L. japonica seedlings were treated with an aqueous solution containing 150 mM of NaCl and aqueous solutions containing various concentrations of Mt. The results revealed that treatment of NaCl-stressed L. japonica seedlings with a 60 µM aqueous solution of Mt significantly enhanced vegetative plant growth by scavenging reactive oxygen species and thus reducing oxidative stress. The latter was evidenced by decreases in electrical conductivity and malondialdehyde (MDA) concentrations. Moreover, Mt treatment led to increases in the NaCl-stressed L. japonica seedlings’ total chlorophyll content, soluble sugar content, and flavonoid content, demonstrating that Mt treatment improved the seedlings’ tolerance of NaCl stress. This was also indicated by the NaCl-stressed L. japonica seedlings exhibiting marked increases in the activities of antioxidant enzymes (superoxide dismutase, peroxidase, catalase, and ascorbate peroxidase) and in photosynthetic functions. Furthermore, Mt treatment of NaCl-stressed L. japonica seedlings increased their expression of phenylalanine ammonia-lyase 1 (PAL1), phenylalanine ammonia-lyase 2 (PAL2), calcium-dependent protein kinase (CPK), cinnamyl alcohol dehydrogenase (CAD), flavanol synthase (FLS), and chalcone synthase (CHS). In conclusion, our results demonstrate that treatment of L. japonica seedlings with a 60 µM aqueous solution of Mt significantly ameliorated the detrimental effects of NaCl stress in the seedlings. Therefore, such treatment has substantial potential for use in safeguarding medicinal plant crops against severe salinity.

The Key Targets of NO-Mediated Post-Translation Modification (PTM) Highlighting the Dynamic Metabolism of ROS and RNS in Peroxisomes.

Nitric oxide (NO) has been firmly established as a key signaling molecule in plants, playing a significant role in regulating growth, development and stress responses. Given the imperative of sustainable agriculture and the urgent need to meet the escalating global demand for food, it is imperative to safeguard crop plants from the effects of climate fluctuations. Plants respond to environmental challenges by producing redox molecules, including reactive oxygen species (ROS) and reactive nitrogen species (RNS), which regulate cellular, physiological, and molecular processes. Nitric oxide (NO) plays a crucial role in plant stress tolerance, acting as a signaling molecule or free radical. NO is involved in various developmental processes in plants through diverse mechanisms. Exogenous NO supplementation can alleviate the toxicity of abiotic stresses and enhance plant resistance. In this review we summarize the studies regarding the production of NO in peroxisomes, and how its molecule and its derived products, (ONOO-) and S-nitrosoglutathione (GSNO) affect ROS metabolism in peroxisomes. Peroxisomal antioxidant enzymes including catalase (CAT), are key targets of NO-mediated post-translational modification (PTM) highlighting the dynamic metabolism of ROS and RNS in peroxisomes.

(Invited) Carbon Nanostructures for Targeted Delivery and Health Monitoring in Plants

To meet the demand for food and bioenergy of a rapidly growing global population requires novel and convergent approaches to enhance photosynthetic organism function. Nanotechnology is enabling the development of targeted and species independent tools for advancing plant bioengineering and precision agriculture.My research group has developed carbon nanotube-based sensors capable of real-time sensing of plant signaling molecules. These nanosensors enabled the creation of plant sentinels that communicate the health status of plants to electronic devices. Near-infrared (nIR) fluorescent single-walled carbon nanotubes (SWCNTs) were designed and interfaced with plant leaves to report hydrogen peroxide (H2O2), a key signaling molecule associated with the onset of plant stress. The sensor nIR fluorescence response (>900 nm) is quenched by H2O2 with selectivity against other stress-associated signaling molecules and within the plant physiological range (10–100 H2O2 μM). In vivo remote nIR imaging of H2O2 sensors enabled optical monitoring of plant health in response to stresses including UV-B light (−11%), high light (−6%), and a pathogen-related peptide (flg22) (−10%), but not mechanical leaf wounding (<3%). The sensor’s high biocompatibility was reflected on similar leaf cell death (<5%) and photosynthetic rates to controls without SWCNT. These optical nanosensors report early signs of stress and will improve our understanding of plant stress communication, provide novel tools for precision agriculture, and optimize the use of agrochemicals in the environment.We also developed targeted carbon-based nanomaterials as tools for precise chemical delivery (carbon dots, CDs) and gene delivery platforms (SWCNTs) to plant organelles (chloroplasts) and vasculature (phloem). A biorecognition approach of coating the nanomaterials with a rationally designed chloroplast targeting peptide improved the delivery of CDs with molecular baskets (TP-β-CD) for delivery of agrochemicals and of plasmid DNA coated SWCNT (TP-pATV1-SWCNT) from 47% to 70% and from 39% to 57% of chloroplasts in leaves, respectively. Plants treated with TP-β-CD (20 mg/L) and TP-pATV1-SWCNT (2 mg/L) had a low percentage of dead cells, 6% and 8%, respectively, similar to controls without nanoparticles, and no permanent cell and chloroplast membrane damage after 5 days of exposure. Orthogonally, the surfaces of carbon dot nanocarriers were functionalized with sucrose, enabling rapid and efficient foliar delivery into the plant phloem, a vascular tissue that transports sugars, signaling molecules, and agrochemicals through the whole plant. The chemical affinity of sucrose molecules to sugar membrane transporters on the phloem cells enhances the uptake of biocompatible carbon dots with β-cyclodextrin molecular baskets (suc-β-CD) that can carry a wide range of agrochemicals. The nanoparticle fluorescence emission properties allowed detection and monitoring of rapid translocation (<40 min) in the vasculature of wheat leaves by confocal and epifluorescence microscopy. The suc-β-CDs more than doubled the delivery of chemical cargoes into the leaf vascular tissue. The sucrose coating of nanoparticles approach enables unprecedented targeted delivery to roots with ≈70% of phloem-loaded nanoparticles delivered to roots.The use of plant biorecognition molecules mediated delivery provides an approach for guiding nanocarriers with their cargoes to plant organelles, cells and tissues and whole plants and engineering safer and efficient agrochemical and biomolecule delivery tools. Communication and actuation of plants mediated by nanosensors and targeted nanostructures can turn plants into technology and lead to a more precise and sustainable agriculture with reduced environmental impact.

Based on BODIPY fluorescent probe for detecting NO in tumour cells, zebrafish and rice roots under abiotic stresses

As a ubiquitous signaling molecule in organisms and plants, NO plays an important role in their physiological and pathological processes. To date, numerous fluorescent probes have been successfully developed for the detection of NO. However, there are still limitations in the ability to simultaneously detect fluctuations of NO in vivo and plants. In this study, we have developed a fluorescent probe (BZD) specifically probe that reacts with NO under aerobic conditions, leading to a disruption of the photoinduced electron transfer (PeT) process from the secondary amine to the core of BODIPY. This disruption results in the emission of a distinct fluorescent signal. The tests showed that BZD had the advantages of low detection limit (28.4 nM), fast detection time (60 s), and successfully demonstrated good imaging ability in cell, zebrafish. Moreover, the probe was used to detect the changes in NO content in rice roots under abiotic stresses, such as heavy metals and salt stress for the first time. Thus, BZD has significant potential to analyze and detect NO in animal cells and insights into the role of NO in plant signaling.

Hydrogen sulfide enhances kiwifruit resistance to soft rot by regulating jasmonic acid signaling pathway

As the third active gas signal molecule in plants, hydrogen sulfide (H2S) plays important roles in physiological metabolisms and biological process of fruits and vegetables during postharvest storage. In the present study, the effects of H2S on enhancing resistance against soft rot caused by Botryosphaeria dothidea and the involvement of jasmonic acid (JA) signaling pathway in kiwifruit during the storage were investigated. The results showed that 20 μL L−1 H2S fumigation restrained the disease incidence of B. dothidea-inoculated kiwifruit during storage, and delayed the decrease of firmness and the increase of soluble solids (SSC) content. H2S treatment increased the transcription levels of genes related to JA biosynthesis (AcLOX3, AcAOS, AcAOC2, and AcOPR) and signaling pathway (AcCOI1, AcJAZ5, AcMYC2, and AcERF1), as well as the JA accumulation. Meanwhile, H2S promoted the expression of defense-related genes (AcPPO, AcSOD, AcGLU, AcCHI, AcAPX, and AcCAT). Correlation analysis revealed that JA content was positively correlated with the expression levels of JA biosynthesis and defense-related genes. Overall, the results indicated that H2S could promote the increase of endogenous JA content and expression of defense-related genes by regulating the transcription levels of JA pathway-related genes, which contributed to the inhibition on the soft rot occurrence of kiwifruit.