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During agricultural production, significant quantities of copper-based nanopesticides (CBNPs) may be released into terrestrial ecosystems through foliar spraying, thereby posing a potential risk of biological transmission via food chains. Consequently, we investigated the trophic transfer of two commonly available commercial CBNPs, Reap2000 (RP) and HolyCu (HC), in a plant-caterpillar terrestrial food chain and evaluated impacts on host microbiota. Upon foliar exposure (with 4 rounds of spraying, totaling 6.0 mg CBNPs per plant), leaf Cu accumulation levels were 726 ± 180 and 571 ± 121 mg kg–1for RP and HC, respectively. HC exhibited less penetration through the cuticle compared to RP (RP: 55.5%; HC: 32.8%), possibly due to size exclusion limitations. While caterpillars accumulated higher amounts of RP, HC exhibited a slightly higher trophic transfer factor (TTF; RP: 0.69 ± 0.20; HC: 0.74 ± 0.17, p> 0.05) and was more likely to be transferred through the food chain. The application of RP promoted the dispersal of phyllosphere microbes and perturbed the original host intestinal microbiota, whereas the HC group was largely host-modulated (control: 65%; RP: 94%; HC: 34%). Integrating multiomics analyses and modeling approaches, we elucidated two pathways by which plants exert bottom-up control over caterpillar health. Beyond the direct transmission of phyllosphere microbes, the leaf microbiome recruited upon exposure to CBNPs further influenced the ingestion behavior and intestinal microbiota of caterpillars via altered leaf metabolites. Elevated Proteobacteriaabundance benefited caterpillar growth with RP, while the reduction of Proteobacteriawith HC increased the risk of lipid metabolism issues and gut disease. The recruited Bacteroidotain the RP phyllosphere proliferated more extensively into the caterpillar gut to enhance stress resistance. Overall, the gut microbes reshaped in RP caterpillars exerted a strong regulatory effect on host health. These findings expand our understanding of the dynamic transmission of host-microbiota interactions with foliar CBNPs exposure, and provide critical insight necessary to ensure the safety and sustainability of nanoenabled agricultural strategies.

Nanoplastics (NPs) are widely detected in the atmosphere and are likely to be deposited on plant leaves. However, our understanding of their foliar uptake, translocation, and trophic transfer profiles is limited due to a lack of quantitative analytical tools to effectively probe mechanisms of action. Here, using synthesized deuterium (2H) stable isotope-labeled polystyrene nanoplastics (2H-PSNPs), the foliar accumulation and translocation of NPs in lettuce and the dynamics of NP transfer along a lettuce–snail terrestrial food chain were investigated. Raman imaging and scanning electron microscopy demonstrated that foliar-applied NPs aggregated on the leaf surface, entered the mesophyll tissue via the stomatal pathway, and eventually translocated to root tissues. Quantitative analysis showed that increasing levels of foliar exposure to 2H-PSNPs (0.1, 1, and 5 mg/L in spray solutions, equivalent to receiving 0.15, 1.5, and 7.5 μg/d of NPs per plant) enhanced NP accumulation in leaves, with concentrations ranging from 0.73 to 15.6 μg/g (dw), but only limited translocation (<5%) to roots. After feeding on 5 mg/L 2H-PSNP-contaminated lettuce leaves for 14 days, snails accumulated NPs at 0.33 to 10.7 μg/kg (dw), with an overall kinetic trophic transfer factor of 0.45, demonstrating trophic dilution in this food chain. The reduced ingestion rate of 3.18 mg/g/day in exposed snails compared to 6.43 mg/g/day can be attributed to the accumulation of 2H-PSNPs and elevated levels of chemical defense metabolites in the lettuce leaves, which decreased the palatability for snails and disrupted their digestive function. This study provides critical quantitative information on the characteristics of airborne NP bioaccumulation and the associated risks to terrestrial food chains.

Nanocarriers (NCs) that can precisely deliver active agents, nutrients and genetic materials into plants will make crop agriculture more resilient to climate change and sustainable. As a research field, nano-agriculture is still developing, with significant scientific and societal barriers to overcome. In this Review, we argue that lessons can be learned from mammalian nanomedicine. In particular, it may be possible to enhance efficiency and efficacy by improving our understanding of how NC properties affect their interactions with plant surfaces and biomolecules, and their ability to carry and deliver cargo to specific locations. New tools are required to rapidly assess NC–plant interactions and to explore and verify the range of viable targeting approaches in plants. Elucidating these interactions can lead to the creation of computer-generated in silico models (digital twins) to predict the impact of different NC and plant properties, biological responses, and environmental conditions on the efficiency and efficacy of nanotechnology approaches. Finally, we highlight the need for nano-agriculture researchers and social scientists to converge in order to develop sustainable, safe and socially acceptable NCs.

Drought is among the most damaging climatic hazards affecting crop productivity and nutritional quality. Here, we investigated the influence of Cu-based materials at mitigating drought stress in soybeans (Glycine max) during the reproductive stage in order to elucidate effects on productivity. Commercial copper oxide (CuO) nanoparticles (NPs), in-house synthesized copper sulfide (CuS) NPs, and copper sulfate (CuSO4) were foliar applied at 10 mg Cu/L daily for 1 week to soybean that were exposed to water deficit at the onset of flowering, and plants were harvested 5 days after exposure. Drought inhibited flower production by 27% compared to the nondrought treatment. Notably, both CuS NPs and ionic Cu mitigated the drought-induced inhibition of flower production, showing 41.7 and 33.3% improvement. CuS NPs exhibited the most positive impact on restoring shoot biomass, pod biomass, and shoot moisture content, increasing values by 53, 96, and 10%, respectively, compared to the drought control plants. The Cu-based materials maintained photosynthetic parameters under drought conditions and modulated oxidative damage by enhancing reactive oxygen species-scavenging enzyme activities. Furthermore, CuO NP treatment increased shoot and pod Cu levels by 624 and 54%, respectively, compared to the drought control plants. Taken together, these findings suggest that Cu-based materials modulate plant protective mechanisms against drought stress during the flowering stage, offering a potentially important nanoenabled strategy to promote biofortified climate resilient crops.

Micro- and nano-plastics (NPs) are found in human milk, blood, tissues, and organs and associate with aberrant health outcomes including inflammation, genotoxicity, developmental disorders, onset of chronic diseases, and autoimmune disorders. Yet, interfacial interactions between plastics and biomolecular systems remain underexplored. Here, we have examined experimentally, in vitro, in vivo, and by computation, the impact of polystyrene (PS) NPs on a host of biomolecular systems and assemblies. Our results reveal that PS NPs essentially abolished the helix-content of the milk protein β-lactoglobulin (BLG) in a dose-dependent manner. Helix loss is corelated with the near stoichiometric formation of β-sheet elements in the protein. Structural alterations in BLG are also likely responsible for the nanoparticle-dependent attrition in binding affinity and weaker on-rate constant of retinol, its physiological ligand (compromising its nutritional role). PS NP-driven helix-to-sheet conversion was also observed in the amyloid-forming trajectory of hen egg-white lysozyme (accelerated fibril formation and reduced helical content in fibrils). Caenorhabditis elegansexposed to PS NPs exhibited a decrease in the fluorescence of green fluorescent protein-tagged dopaminergic neurons and locomotory deficits (akin to the neurotoxin paraquat exposure). Finally, in silico analyses revealed that the most favorable PS/BLG docking score and binding energies corresponded to a pose near the hydrophobic ligand binding pocket (calyx) of the protein where the NP fragment was found to make nonpolar contacts with side-chain residues via the hydrophobic effect and van der Waals forces, compromising side chain/retinol contacts. Binding energetics indicate that PS/BLG interactions destabilize the binding of retinol to the protein and can potentially displace retinol from the calyx region of BLG, thereby impairing its biological function. Collectively, the experimental and high-resolution in silico data provide new insights into the mechanism(s) by which PS NPs corrupt the bimolecular structure and function, induce amyloidosis and onset neuronal injury, and drive aberrant physiological and behavioral outcomes.

There is a need to develop new and sustainable agricultural technologies to help provide global food security, and nanoscale materials show promising results in this area. In this study, mesoporous silica nanoparticles (MSNs) and chitosan-coated mesoporous silica nanoparticles (CTS-MSNs) were synthesized and applied to soybeans (Glycine max) by two different strategies in greenhouse and field studies to study the role of dissolved silicic acid and chitosan in enhancing plant growth and suppressing disease damage caused by Fusarium virguliforme. Plant growth and health were assessed by measuring the soybean biomass and chlorophyll content in both healthy and Fusarium-infected plants at harvest. In the greenhouse study, foliar and seed applications with 250 mg/L nanoparticle treatments were compared. A single seed treatment of MSNs reduced disease severity by 30% and increased chlorophyll content in both healthy and infected plants by 12%. Based on greenhouse results, seed application was used in the follow-up field study and MSNs and CTS-MSNs reduced disease progression by 12 and 15%, respectively. A significant 32% increase was observed for chlorophyll content for plants treated with CTS-MSNs. Perhaps most importantly, nanoscale silica seed treatment significantly increased (23–68%) the micronutrient (Zn, Mn, Mg, K, B) content of soybean pods, suggesting a potential sustainable strategy for nano-enabled biofortification to address nutrition insecurity. Overall, these findings indicate that MSN and CTS-MSN seed treatments in soybeans enable disease suppression and increase plant health as part of a nano-enabled strategy for sustainable agriculture.

In the current work, the foliar application of selenium nanomaterials (Se0NMs) suppressed sheath blight in rice (Oryza sativa). The beneficial effects were nanoscale specific and concentration dependent. Specifically, foliar amendment of 5 mg/L Se0NMs decreased the disease severity by 68.8% in Rhizoctonia solani-infected rice; this level of control was 1.57- and 2.20-fold greater than that of the Se ions with equivalent Se mass and a commercially available pesticide (Thifluzamide). Mechanistically, (1) the controlled release ability of Se0NMs enabled a wider safe concentration range and greater bioavailability to Se0NMs, and (2) transcriptomic and metabolomic analyses demonstrated that Se0NMs simultaneously promoted the salicylic acid- and jasmonic-acid-dependent acquired disease resistance pathways, antioxidative system, and flavonoid biosynthesis. Additionally, Se0NMs improved rice yield by 31.1%, increased the nutritional quality by 6.4–7.2%, enhanced organic Se content by 44.8%, and decreased arsenic and cadmium contents by 38.7 and 42.1%, respectively, in grains as compared with infected controls. Human simulated gastrointestinal tract model results showed that the application of Se0NMs enhanced the bioaccessibility of Se in grains by 22.0% and decreased the bioaccessibility of As and Cd in grains by 20.3 and 13.4%, respectively. These findings demonstrate that Se0NMs can serve as an effective and sustainable strategy to increase food quality and security.

Nanoenabled strategies have recently attracted attention as a sustainable platform for agricultural applications. Here, we present a mechanistic understanding of nanobiointeraction through an orthogonal investigation. Pristine (nS) and stearic acid surface-modified (cS) sulfur nanoparticles (NPs) as a multifunctional nanofertilizer were applied to tomato (Solanum lycopersicumL.) through soil. Both nS and cS increased root mass by 73% and 81% and increased shoot weight by 35% and 50%, respectively, compared to the untreated controls. Bulk sulfur (bS) and ionic sulfate (iS) had no such stimulatory effect. Notably, surface modification of S NPs had a positive impact, as cS yielded 38% and 51% greater shoot weight compared to nS at 100 and 200 mg/L, respectively. Moreover, nS and cS significantly improved leaf photosynthesis by promoting the linear electron flow, quantum yield of photosystem II, and relative chlorophyll content. The time-dependent gene expression related to two S bioassimilation and signaling pathways showed a specific role of NP surface physicochemical properties. Additionally, a time-dependent Global Test and machine learning strategy applied to understand the NP surface modification domain metabolomic profiling showed that cS increased the contents of IA, tryptophan, tomatidine, and scopoletin in plant leaves compared to the other treatments. These findings provide critical mechanistic insights into the use of nanoscale sulfur as a multifunctional soil amendment to enhance plant performance as part of nanoenabled agriculture.

Copper (Cu) is an element widely used as a pesticide for the control of plant diseases. Cu is also known to influence a range of plant secondary metabolisms. However, it is not known whether Cu influences the levels of the major metabolites in hemp (Cannabis sativaL.), tetrahydrocannabinol (THC) and cannabidiol (CBD). This study investigated the impact of Cu on the levels of these cannabinoids in two hemp cultivars, Wife and Merlot, under field conditions, as a function of harvest time (August–September), Cu type (nano, bulk, or ionic), and dose (50, 100, and 500 ppm). In Wife, Cu caused significant temporal increases in THC and CBD production during plant growth, reaching increases of 33% and 31% for THC and 51% and 16.5% for CBD by harvests 3 and 4, respectively. CuO nanoparticles at 50 and 100 ppm significantly increased THC and CBD levels, compared to the control, respectively, by 18% and 27% for THC and 19.9% and 33.6% for CBD. These nanospecific increases coincided with significantly more Cu in the inflorescences (buds) than in the control and bulk CuO treatments. Contrarily, no temporal induction of the cannabinoids by Cu was noticed in Merlot, suggesting a cultivar-specific response to Cu. However, overall, in Merlot, Cu ions, but not particulate Cu, induced THC and CBD levels by 27% and 36%, respectively, compared to the control. Collectively, our findings provide information with contrasting implications in the production of these cannabinoids, where, dependent on the cultivar, metabolite levels may rise above the 0.3% regulatory threshold for THC but to a more profitable level for CBD. Further investigations with a wider range of hemp cultivars, CuO nanoparticle (NP) doses, and harvest times would clarify the significance and broader implications of the findings.

La2O3nanoparticles (NPs) have shown great potential in agriculture, but cracking of plant sensitive tissue could occur during application, resulting in a poor appearance, facilitating entry for insects and fungi, and increasing economic losses. Herein, exocarp cracking mechanisms of tomato (Solanum lycopersicumL.) fruit in response to La2O3NPs were investigated. Tomato plants were exposed to La2O3NPs (0–40 mg/L, 90 days) by a split-root system under greenhouse condition. La2O3NPs with high concentrations (25 and 40 mg/L) increased the obvious cracking of the fruit exocarp by 20.0 and 22.7%, respectively. After exposure to 25 mg/L La2O3NPs, decreased thickness of the cuticle and cell wall and lower wax crystallization patterns of tomato fruit exocarp were observed. Biomechanical properties (e.g., firmness and stiffness) of fruit exocarp were decreased by 34.7 and 25.9%, respectively. RNA-sequencing revealed that the thinner cuticle was caused by the downregulation of cuticle biosynthesis related genes; pectin remodeling, including the reduction in homogalacturonan (e.g., LOC101264880) and rhamnose (e.g., LOC101248505), was responsible for the thinner cell wall. Additionally, genes related to water and abscisic acid homeostasis were significantly upregulated, causing the increases of water and soluble solid content of fruit and elevated fruit inner pressure. Therefore, the thinner fruit cuticle and cell wall combined with the higher inner pressure caused fruit cracking. This study improves our understanding of nanomaterials on important agricultural crops, including the structural reconstruction of fruit exocarp contributing to NPs-induced cracking at the molecular level.

Anaplastic lymphoma kinase (ALK)-fusion sarcomas are rare part of the emerging theoretically targetable tyrosine kinase RAS::MAPKpathway fusion myopericytic-ovoid sarcomas. We report our clinicopathologic and treatment experience with an ALKfusion sarcoma. A novel ELKS/RAB6-interacting/CAST family member 1–unaligned ALKfusion infiltrative nonmetastatic low-grade sarcoma of the right hand of a 15-month-old male was treated with crizotinib, an ALKtyrosine kinase inhibitor as oral monotherapy, inducing complete radiographic and clinical resolution by 10 months and sustained response now over 12 months after elective discontinuation. Crizotinib can successfully be used to treat unresectable novel ALKfusion sarcomas.

The continued acquisition and propagation of antibiotic resistance genes (ARGs) in the environment confound efforts to manage the global rise in antibiotic resistance. Here, CRISPR-Cas9/sgRNAs carried by nitrogen-doped carbon dots (NCDs) were developed to precisely target multi-“high-risk” ARGs (tet, cat, and aph(3′)-Ia) commonly detected in the environment. NCDs facilitated the delivery of Cas9/sgRNAs to Escherichia coli(E. coli) without cytotoxicity, achieving sustained elimination of target ARGs. The elimination was optimized using different weight ratios of NCDs and Cas9 protein (1:1, 1:20, and 1:40), and Cas9/multi sgRNAs were designed to achieve multi-cleavage of ARGs in either a single strain or mixed populations. Importantly, NCDs successfully facilitated Cas9/multi sgRNAs for resensitization of antibiotic-resistant bacteria in soil (approaching 50%), whereas Cas9/multi sgRNAs alone were inactivated in the complex environment. This work highlights the potential of a fast and precise strategy to minimize the reservoir of antibiotic resistance in agricultural system.

Molybdenum disulfide (nano-MoS2) nanomaterials have shown great potential for biomedical and catalytic applications due to their unique enzyme-mimicking properties. However, their potential agricultural applications have been largely unexplored. A key factor prior to the application of nano-MoS2in agriculture is understanding its behavior in a complex soil–plant system, particularly in terms of its transformation. Here, we investigate the distribution and transformation of two types of nano-MoS2(MoS2nanoparticles and MoS2nanosheets) in a soil–soybean system through a combination of synchrotron radiation-based X-ray absorption near-edge spectroscopy (XANES) and single-particle inductively coupled plasma mass spectrometry (SP-ICP-MS). We found that MoS2nanoparticles (NPs) transform dynamically in soil and plant tissues, releasing molybdenum (Mo) and sulfur (S) that can be incorporated gradually into the key enzymes involved in nitrogen metabolism and the antioxidant system, while the rest remain intact and act as nanozymes. Notably, there is 247.9 mg/kg of organic Mo in the nodule, while there is only 49.9 mg/kg of MoS2NPs. This study demonstrates that it is the transformation that leads to the multifunctionality of MoS2, which can improve the biological nitrogen fixation (BNF) and growth. Therefore, MoS2NPs enable a 30% increase in yield compared to the traditional molybdenum fertilizer (Na2MoO4). Excessive transformation of MoS2nanosheets (NS) leads to the overaccumulation of Mo and sulfate in the plant, which damages the nodule function and yield. The study highlights the importance of understanding the transformation of nanomaterials for agricultural applications in future studies.

A variety of atmospheric lead-based chalcogenide particles (PbXn, where X = S or O) present a significant risk to environmental and public health. Foliar uptake dominates atmospheric Pb contamination of crops, although the precise mechanisms are unclear, particularly for different types of PbXn. In this paper, the effects of 5 atmospheric PbXn(PbS-S, PbS-Q, Pb3O4, PbO2and PbO) properties, including particle lateral size, hydrodynamic size, zeta potential, contact angle, BET surface area and Ksp, on the adhesion and absorption of eggplant (Solanum melongenaL.) leaves were studied. The adhesion and absorption of PbXnin leaves were quantitatively distinguished by a water–EDTA-2Na solution step-by-step rinsing method. Adhesion accounted for 33–98% of the total foliar uptake and caused overestimation to a varying extent of total foliar absorption of different PbXn(uptake includes adhesion and absorption). The contribution of stomata and cuticle to PbXnparticle absorption was also tested. Cuticular pathway contributed to 19–69% of the total absorption. Multiple linear regression and path analyses revealed that zeta potential and hydrodynamic size were the two most positive factors for leaf adhesion, while for absorption it was the opposite. BET surface area was the most important property of PbXnto be absorbed through the cuticular/stomatal pathway. This study provides an important insight into foliar uptake mechanisms of common atmospheric lead-based particles and can be used to construct more accurate and environmentally ecological risk assessments of Pb contaminants.

Enhancing the delivery efficiency of NPK fertilizers benefits both crops and the environment through moderating the supplied dosage of nutrients in the soil, avoiding side reactions, maximizing absorption by the plant, and minimizing leaching and runoff. Bio-based materials such as cellulose are ideal scaffolds for nutrient delivery due to their inherent biocompatibility, biodegradability, and significant water uptake. In this work, nanocellulose-based hydrogels were regenerated from mixed softwood in acidic media and loaded with NPK by immersion in varied concentrations of an NPK-rich fertilizer solution. High loading of NPK was achieved within the hydrogel, but immersion in the matrix provided only slight slowing of nutrient release compared to rapid solubility of conventional formulations. Densification, crosslinking, and coating of the hydrogels with beeswax were ineffective strategies to further slow NPK release. Following these results, both gas and solution-phase esterification reactions of the cellulosic matrix with hexanoyl chloride were performed after NPK loading to introduce a hydrophobic surface layer. While solution-phase modification led to phosphorus leaching and was overall ineffective in altering nutrient release, the gas-phase modification slowed the release of P and K by more than an order of magnitude. Moreover, it was found that varying both the properties of the hydrophobic surface layer and the nutrient loading provide a means to tune release rates. Overall, this work demonstrates the potential of nanocellulose-based hydrogels to be used as an environmentally safe and sustainable vehicle for the controlled release of nutrients in agricultural applications.

Nanotechnology applications in agriculture have received considerable attention with the aim of improving crop production, nutritional quality and food safety. The comparative effects of four different iron-based nanomaterials (Fe NMs, 50 mg Fe L−1) on wheat were investigated following foliar application in a Cd-contaminated field trial. The results showed that α-Fe2O3NMs, γ-Fe2O3NMs and Fe3O4NMs significantly reduced the Cd concentration in wheat grain (by 60.9%, 44.7% and 50.1%, respectively) below the established Cd safety threshold (0.1 mg kg−1), but only γ-Fe2O3NMs could simultaneously improve grain yield (by 8.6%) and the PA/Fe molar ratio in white flour (17.9%) compared to the control. Furthermore, α-Fe2O3, γ-Fe2O3and Fe3O4NMs significantly lowered the dietary Cd exposure and health risk by 44.2–57.9% by reducing Cd concentrations and bioaccessibility in wheat flour. The ionomic analysis demonstrated that with the exception of nZVI, elemental homeostasis was more sensitive to Fe NMs in the wheat leaf and glume, and a significant negative correlation between Cd and P, as well as Mo and Ca were observed. Overall, these findings highlight the significant potential of γ-Fe2O3NMs as an effective foliar agent for safe wheat production and biofortification in nano-enabled agriculture.

Phosphorus (P) is critical for crop production but has a high nutrient use inefficiency. Tomato was grown in soil amended with five P-sources, used as-is, or embedded within a biodegradable polymer, polyhydroxyalkanoate (PHA). Correlation analysis identified treatments that maintain plant growth, improve bioavailable soil P, and reduce P loss. Three performance classes were identified: (i) micro- and nanohydroxyapatite, which did not increase bioavailable P, plant P-uptake, or change P in runoff/leaching compared to controls; (ii) monocalcium phosphate (MCP), dicalcium phosphate (DCP), calcium pyrophosphate nanoparticles (CAP), and PHA-MCP that increased P-uptake and/or bioavailable P but also increased P loss in runoff/leaching; and (iii) PHA-DCP and PHA-CAP, where increased bioavailable P and plant P-uptake were achieved with minimal P loss in runoff/leaching. In addition to identifying treatments that maintain plant growth, increase bioavailable P, and minimize nutrient loss, correlation plots also revealed that (i) bioavailable P was a good indicator of plant P-uptake; (ii) leached P could be predicted from water solubility; and (iii) P loss through runoff versus leaching showed similar trends. This study highlights that biopolymers can promote plant P-uptake and improve bioavailable soil P, with implications for mitigating the negative environmental impacts of P loss from agricultural systems.

Rapid population growth, global conflict, and the COVID-19 pandemic are all contributing to the surge in global food insecurity.Nanoparticles (NPs) show promise toward alleviating food insecurity as several NPs used in greenhouse and field studies are outperforming conventional agrochemicals.NP characteristics determine their uptake and translocation into plants.Literature precedent demonstrates that it is possible to tune critical NP properties such as size, surface charge, shape, surface modifications, and transformations to impact the NP’s performance within the plant.While studies done to date are promising, more systematic studies with the most promising NPs are needed to achieve the full potential benefit of NP-enabled agriculture.

To investigate the mechanisms by which g-C3N4alleviates metal(loid)-induced phytotoxicity, rice seedlings were exposed to 100 and 250 mg/kg graphitic carbon nitride (g-C3N4) with or without coexposure to 10 mg/kg Cd and 50 mg/kg As for 30 days. Treatment with 250 mg/kg g-C3N4significantly increased shoot and root fresh weight by 22.4–29.9%, reduced Cd and As accumulations in rice tissues by 20.6–26.6%, and elevated the content of essential nutrients (e.g., K, S, Mg, Cu, and Zn) compared to untreated controls. High-throughput sequencing showed that g-C3N4treatment increased the proportion of plant-growth-promoting endophytic bacteria, including Streptomyces, Saccharimonadales, and Thermosporothrix, by 0.5–3.30-fold; these groups are known to be important to plant nutrient assimilation, as well as metal(loid) resistance and bioremediation. In addition, the population of Deinococcuswas decreased by 72.3%; this genus is known to induce biotransformation As(V) to As(III). Metabolomics analyses highlighted differentially expressed metabolites (DEMs) involved in the metabolism of tyrosine metabolism, pyrimidines, and purines, as well as phenylpropanoid biosynthesis related to Cd/As-induced phytotoxicity. In the phenylpropanoid biosynthesis pathway, the increased expression of 4-coumarate (1.13-fold) and sinapyl alcohol (1.26-fold) triggered by g-C3N4coexposure with Cd or As played a critical role in promoting plant growth and enhancing rice resistance against metal(loid) stresses. Our findings demonstrate the potential of g-C3N4to enhance plant growth and minimize the Cd/As-induced toxicity in rice and provide a promising nanoenabled strategy for remediating heavy metal(loid)-contaminated soil.

With the widespread use of nanoenabled agrochemicals, it is essential to evaluate the food safety of nanomaterials (NMs)-treated vegetable crops in full life cycle studies as well as their potential impacts on human health. Tomato seedlings were foliarly sprayed with 50 mg/L ZnO NMs, including ZnO quantum dots (QDs) and ZnO nanoparticles once per week over 11 weeks. The foliar sprayed ZnO QDs increased fruit dry weight and yield per plant by 39.1% and 24.9, respectively. It also significantly increased the lycopene, amino acids, Zn, B, and Fe in tomato fruits by 40.5%, 15.1%, 44.5%, 76.2%, and 12.8%, respectively. The tomato fruit metabolome of tomatoes showed that ZnO NMs upregulated the biosynthesis of unsaturated fatty acids and sphingolipid metabolism and elevated the levels of linoleic and arachidonic acids. The ZnO NMs-treated tomato fruits were then digested in a human gastrointestinal tract model. The results of essential mineral release suggested that the ZnO QDs treatment increased the bioaccessibility of K, Zn, and Cu by 14.8–35.1% relative to the control. Additionally, both types of ZnO NMs had no negative impact on the α-amylase, pepsin, and trypsin activities. The digested fruit metabolome in the intestinal fluid demonstrated that ZnO NMs did not interfere with the normal process of human digestion. Importantly, ZnO NMs treatments increased the glycerophospholipids, carbohydrates, amino acids, and peptides in the intestinal fluids of tomato fruits. This study suggests that nanoscale Zn can be potentially used to increase the nutritional value of vegetable crops and can be an important tool to sustainably increase food quality and security.

The increase in the global use of phosphorus (P) fertilizers for crop production has generated a series of unintended negative consequences. In response, there is growing interest in developing new fertilizers that curb adverse effects. Among them, amorphous calcium phosphate (ACP) is a viable alternative because of its tunable solubility for P release, high specific surface area, and ability to be doped with vital microelements essential for crops. Herein, we prepared a series of citrate-stabilized ACP nanoparticles (ACPc) doped with micronutrients (B, Cu, Mg, and Zn) and analyzed their dissolution and nutrient release characteristics. Comparative analysis of undissolved ACPc, released ions, and pH of eluted buffer showed a strong positive correlation between the P release rate and the corresponding change in buffer pH. The competitive advantage of ACPc against a monocalcium phosphate (MCP), a conventional commercial fertilizer, for providing P nutrition to plants was tested in lettuce (Lactuca sativa) plants in a greenhouse study. The results showed that undoped ACPc stimulated a 20% higher lettuce crop yield than that of MCP, and the doping with multimicronutrients increased the yield by 22%. More importantly, P resource use efficiency (RUE), calculated based on crop yield and P lost in leachate, was significantly higher in all ACPc than MCP and was about an order of magnitude higher in undoped and multimicronutrient doped ACPc. These results demonstrate that multimicronutrient doping in ACPc is a more efficient and sustainable approach for the dual delivery of P and micronutrients and thus contributes toward meeting the global food demands while minimizing the negative environmental impacts of agriculture.

Although silicon‐based nanomaterials (Si‐based NMs) can promote crop yield and alleviate biotic and abiotic stress, the underlying performance mechanisms are unknown. In the present study, the effect of the root application of Si‐based NMs on the physiological responses of cherry radish (Raphanus sativusL.) was evaluated in a life cycle experiment. Root exposure to 0.1% (w/w) Si‐based NMs significantly increased total fresh weight, total chlorophyll and carotenoids by 36.0%, 14.2% and 18.7%, respectively, relative to untreated controls. The nutritional content of the edible tissue was significantly enhanced, with an increase of 23.7% in reducing sugar, 24.8% in total sugar, and 232.7% in proteins; in addition, a number of nutritional elements (Cu, Mn, Fe, Zn, K, Ca, and P) were increased. Si‐based NMs exposure positively altered the phytohormone network and decreased abscisic acid content, both of which promoted radish fresh weight. LC‐MS‐based metabolomic analysis shows that Si‐based NMs increased the contents of most carbohydrates (e.g., α‐D‐glucose, acetylgalactosamine, lactose, fructose, etc.) and amino acids (e.g., asparagine, glutamic acid, glutamine, valine, arginine, etc.), subsequently improving overall nutritional values. Overall, nanoscale Si‐based agrochemicals have significant potential as a novel strategy for the biofortification of vegetable crops in sustainable nano‐enabled agriculture. The present work investigates the underlying mechanisms by which Si‐based nanosheets enhance the yield and quality of vegetable crops. The results suggest that Si‐based nanosheets positively altered the phytohormone networks and enhanced the overall nutritional quality in the edible portions of cherry radish. Thus, nanoscale agrochemicals have exhibited significant potential impacts on sustainable agriculture.

In the current study, foliar spray with lanthanum (La) based nanomaterials (La10Si6O27nanorods, La10Si6O27nanoparticle, La(OH)3nanorods, and La2O3nanoparticle) suppressed the occurrence of sheath blight (Rhizoctonia solani) in rice. The beneficial effects were morphology-, composition-, and concentration-dependent. Foliar application of La10Si6O27nanorods (100 mg/L) yielded the greatest disease suppression, significantly decreasing the disease severity by 62.4% compared with infected controls; this level of control was 2.7-fold greater than the commercially available pesticide (Thifluzamide). The order of efficacy was as follows: La10Si6O27nanorods > La10Si6O27nanoparticle > La(OH)3nanorods > La2O3nanoparticle. Mechanistically, (1) La10Si6O27nanorods had greater bioavailability, slower dissolution, and simultaneous Si nutrient benefits; (2) transcriptomic and metabolomic analyses revealed that La10Si6O27nanorods simultaneously strengthened rice systemic acquired resistance, physical barrier formation, and antioxidative systems. Additionally, La10Si6O27nanorods improved rice yield by 35.4% and promoted the nutritional quality of the seeds as compared with the Thifluzamide treatment. A two-year La10Si6O27nanorod exposure had no effect on soil health based on the evaluated chemical, physical, and biological soil properties. These findings demonstrate that La based nanomaterials can serve as an effective and sustainable strategy to safeguard crops and highlight the importance of nanomaterial composition and morphology in terms of optimizing benefit.

Soybean (Glycine max) is a crop of global significance and has low reliance on N fertilizers due to its biological nitrogen fixation (BNF) capacity, which harvests ambient N2as a critical ecosystem service. BNF can be severely compromised by abiotic stresses. Enhancing BNF is increasingly important not only to alleviate global food insecurity but also to reduce the environmental impact of agriculture by decreasing chemical fertilizer inputs. However, this has proven challenging using current genetic modification or bacterial nodulation methods. Here, we demonstrate that a single application of a low dose (10 mg/kg) of molybdenum disulfide nanoparticles (MoS2NPs) can enhance soybean BNF and grain yield by 30%, compared with conventional molybdate fertilizer. Unlike molybdate, MoS2NPs can more sustainably release Mo, which then is effectively incorporated as a cofactor for the synthesis of nitrogenase and molybdenum-based enzymes that subsequently enhance BNF. Sulfur is also released sustainably and incorporated into biomolecule synthesis, particularly in thiol-containing antioxidants. The superior antioxidant enzyme activity of MoS2NPs, together with the thiol compounds, protect the nodules from reactive oxygen species (ROS) damage, delay nodule aging, and maintain the BNF function for a longer term. The multifunctional nature of MoS2NPs makes them a highly effective strategy to enhance plant tolerance to abiotic stresses. Given that the physicochemical properties of nanomaterials can be readily modulated, material performance (e.g., ROS capturing capacity) can be further enhanced by several synthesis strategies. This study thus demonstrates that nanotechnology can be an efficient and sustainable approach to enhancing BNF and crop yield under abiotic stress and combating global food insecurity.

Molybdenum disulfide (MoS2) nanosheets are increasingly applied in several fields, but effective and accurate strategies to fully characterize potential risks to soil ecosystems are lacking. We introduce a coelomocyte-based in vivoexposure strategy to identify novel adverse outcome pathways (AOPs) and molecular endpoints from nontransformed (NTMoS2) and ultraviolet-transformed (UTMoS2) MoS2nanosheets (10 and 100 mg Mo/L) on the earthworm Eisenia fetidausing nontargeted lipidomics integrated with transcriptomics. Machine learning-based digital pathology analysis coupled with phenotypic monitoring was further used to establish the correlation between lipid profiling and whole organism effects. As an ionic control, Na2MoO4exposure significantly reduced (61.2–79.5%) the cellular contents of membrane-associated lipids (glycerophospholipids) in earthworm coelomocytes. Downregulation of the unsaturated fatty acid synthesis pathway and leakage of lactate dehydrogenase (LDH) verified the Na2MoO4-induced membrane stress. Compared to conventional molybdate, NTMoS2inhibited genes related to transmembrane transport and caused the differential upregulation of phospholipid content. Unlike NTMoS2, UTMoS2specifically upregulated the glyceride metabolism (10.3–179%) and lipid peroxidation degree (50.4–69.4%). Consequently, lipolytic pathways were activated to compensate for the potential energy deprivation. With pathology image quantification, we report that UTMoS2caused more severe epithelial damage and intestinal steatosis than NTMoS2, which is attributed to the edge effect and higher Mo release upon UV irradiation. Our results reveal differential AOPs involving soil sentinel organisms exposed to different Mo forms, demonstrating the potential of liposome analysis to identify novel AOPs and furthermore accurate soil risk assessment strategies for emerging contaminants.

The use of nanotechnology to suppress crop diseases has attracted significant attention in agriculture. The present study investigated the antifungal mechanism by which aloe vera extract gel-biosynthesized (AVGE) selenium nanoparticles (Se NPs) suppressed Fusarium-induced wilt disease in lettuce (Lactuca sativa). AVGE Se NPs were synthesized by utilizing sodium selenite as a Se source and AVGE as a biocompatible capping and reducing agent. Over 21 d, 2.75% of total AVGE Se NPs was dissolved into Se ions, which was more than 8-fold greater than that of bare Se NPs (0.34%). Upon exposure to soil applied AVGE Se NPs at 50 mg/kg, fresh shoot biomass was significantly increased by 61.6 and 27.8% over the infected control and bare Se NPs, respectively. As compared to the infected control, the shoot levels of citrate, isocitrate, succinate, malate, and 2-oxo-glutarate were significantly upregulated by 0.5–3-fold as affected by both Se NPs. In addition, AVGE Se NPs significantly increased the shoot level of khelmarin D, a type of coumarin, by 4.40- and 0.71-fold over infected controls and bare Se NPs, respectively. Additionally, AVGE Se NPs showed greater upregulation of jasmonic acid and downregulation of abscisic acid content relative to bare Se NPs in diseased shoots. Moreover, the diversity of bacterial endophytes was significantly increased by AVGE Se NPs, with the values of Shannon index 40.2 and 9.16% greater over the infected control and bare Se NPs. Collectively, these findings highlight the significant potential of AVGE Se NPs as an effective and biocompatible strategy for nanoenabled sustainable crop protection.

With a global population racing toward 10 billion people in the next 25 years, the challenge to global food production, storage, and distribution will be immense. There are a range of technologies and strategies that could, at least in theory, be successfully applied to improve food security in a sustainable way. Nanotechnology is one such strategy that is being increasingly recognized as having great potential. Here, we present examples of how nanotechnology can be applied from farm to fork and help to improve availability, access, and utilization of food. We also discuss major challenges associated with efficient production and deployment at industrial scale, regulatory and safety concerns, and consumer acceptance. Recognizing that issues of food security are highly contextual, we recommend increasing discipline convergence and multisectorial collaborations from a one-health perspective to guide the development and commercialization of impactful nano-enabled solutions that will combat global food insecurity.

Orthogonal techniques were used to track manganese nanoparticles (MnNPs) in Capsicum annuumL. leaf tissue and cell compartments and subsequently to explain the mechanism of uptake, translocation, and cellular interaction. C. annuumL was cultivated and foliarly exposed to MnNPs (100 mg/L, 50 mL/per leaf) before analysis by using scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDS) as well as dark-field hyperspectral and two-photon microscopy. We visualized the internalization of MnNP aggregates from the leaf surface and observed particle accumulation in the leaf cuticle and epidermis as well as spongy mesophyll and guard cells. These techniques enabled a description of how MnNPs cross different plant tissues as well as selectively accumulate and translocate in specific cells. We also imaged abundant fluorescent vesicles and vacuoles containing MnNPs, indicating likely induction of autophagy processes in C. annuumL., which is the bio-response upon storing or transforming the particles. These findings highlight the importance of utilizing orthogonal techniques to characterize nanoscale material fate and distribution with complex biological matrices and demonstrate that such an approach offers a significant mechanistic understanding that can inform both risk assessment and efforts aimed at applying nanotechnology to agriculture.

Increasing the capacity of biological nitrogen fixation (BNF) is an effective strategy to enhance food security while simultaneously reducing the carbon and nitrogen footprint of agriculture. Nanotechnology offers several pathways to enhance BNF successfully.

Nickel (Ni) is a trace element beneficial for plant growth and development and could improve crop yield by stimulating urea decomposition and nitrogen-fixing enzyme activity. A full life cycle study was conducted to compare the long-term effects of soil-applied NiO nanoparticles (n-NiO), NiO bulk (b-NiO), and NiSO4at 10–200 mg kg–1on plant growth and nutritional content of soybean. n-NiO at 50 mg kg–1significantly promoted the seed yield by 39%. Only 50 mg kg–1n-NiO promoted total fatty acid content and starch content by 28 and 19%, respectively. The increased yield and nutrition could be attributed to the regulatory effects of n-NiO, including photosynthesis, mineral homeostasis, phytohormone, and nitrogen metabolism. Furthermore, n-NiO maintained a Ni2+supply for more extended periods than NiSO4, reducing potential phytotoxicity concerns. Single-particle inductively coupled plasma mass spectrometry (sp-ICP-MS) for the first time confirmed that the majority of the Ni in seeds is in ionic form, with only 28–34% as n-NiO. These findings deepen our understanding of the potential of nanoscale and non-nanoscale Ni to accumulate and translocate in soybean, as well as the long-term fate of these materials in agricultural soils as a strategy for nanoenabled agriculture.

With the rapid increase in global population that is anticipated over the coming decades, more food will need to be produced to meet the increasing demand. The current agricultural production system is unable to meet this challenge, and as such, crop cultivation will need to occur under more marginal conditions. Soil salinization and the consequent salt stress on crops will become increasingly problematic. In this study, we prepared two kinds of biochar nanoparticles (NPs) (particle size 253 and 259 nm) from rice and corn straw at 350 °C and investigated their use as a soil amendment to alleviate salt stress (2000 mg kg−1biochar NPs; 1000/2000 mg kg−1NaCl) on tomato seedlings. After four weeks of growth, the biomass of tomato seedlings was reduced by 48.7% under 2000 mg kg−1NaCl treatment. With rice straw biochar NP application, the biomass increased by 13.1% over the stress controls. In addition, chlorophyll (SPAD value) was increased by 46.7% with rice straw biochar NPs. The rice straw biochar NPs inhibited the transfer of Na from roots to shoots; the Na translocation factor (TF) was 0.46, which is significantly lower than the corresponding value (0.72) for the saline stress controls. The corn straw biochar NPs also contributed to salt stress alleviation in tomato, although the effects were lower than those with rice straw biochar NPs, and there was no reduction in Na transport. However, at lower levels of salt stress with 1000 mg kg−1NaCl treatment, there was little difference in the effects of the two biochar nanoparticles. These findings suggest that straw-derived biochar may be an effective soil amendment to increase the salt stress tolerance of crop species and can serve as an effective tool to facilitate food production under marginal soil conditions.

Heavy metals with opposite charges (e.g., arsenic and lead) generally have opposite environmental behaviors. Nano-enabled strategies to concurrently inhibit their accumulation in crops remain elusive. Here, nano-TiO2with an anatase (NAT) or rutile (NRT) structure or bulk TiO2(BT) was used at 10, 100, and 1000 mg L−1to amend hydroponic rice seedling systems co-contaminated with arsenic (1 mg L−1) and lead (2 or 10 mg L−1) for mechanistic understanding of contaminant interactions. A simultaneous decrease of arsenic and lead bioaccumulation in rice plants and their retention in the root iron plaque were achieved by significant metal sorption to 1000 mg L−1NAT and NRT. The arsenic uptake mitigation by NRT (82–93%) was much higher than that by NAT (46–65%), while their lead uptake inhibition was comparable (47–89% for NRT vs.37–78% for NAT). When the lead/arsenic exposure ratio increased, 100 mg L−1nano-TiO2and BT at all doses also significantly reduced the root metal content, attributable to their enhanced sorption on TiO2and iron plaque. TiO2amendment posed no risk to the plant and completely alleviated oxidative stress from exposure thus restoring it to healthy control levels. Our findings highlight the potential application of 1000 mg L−1nano-TiO2, particularly with a rutile structure, for combined arsenic and lead reduction in rice, effectively enhancing both food safety and human health.

Loss of crop yield to pathogen damage seriously threatens efforts to achieve global food security. In the present work, lanthanum (La) based nanomaterials (NMs) with different morphologies and compositions, including LaPO4nanorods (NRs, 92.5 × 11.6 nm), LaPO4nanoparticles (NPs, 110.9 nm), La2S3NPs (38.6 nm), and La2O3NPs (55.5 nm), were investigated for their control of bacterial pathogen Ralstonia solanacearumon tomato (Solanum lycopersicum). Foliar application of LaPO4NRs (50–200 mg L−1) significantly suppressed pathogen infection, with 100 mg L−1decreasing disease incidence by 71.4% as compared with infected control. At 100 mg L−1, the disease control efficacy of different La based NMs followed the order of LaPO4NPs > LaPO4NRs La2S3NPs > La2O3NPs. Additionally, disease suppression efficacy with LaPO4NPs was 4.6-fold greater than the additive equivalent of La and P ions. Mechanistically, LaPO4NPs could steadily supply low level La ions to pathogen infected tomatoes to bind and activate calmodulin, with subsequent enhancement of phenylalanine ammonia lyase activity by 88.9%, as well as the upregulation of pathogenesis-related gene (e.g., PR1, PR-P2, and P4) expression by 13.3–742.1%. Additionally, La based NMs amendment enhanced the flavonoid and polyphenol content by 13.7–44.8%, and antioxidative enzyme activity by 11.4–124.3%, decreasing the oxidative stress in tomato shoots by 16.4–25.4%. The higher disease control ability of LaPO4NPs than other La based NMs was due to its greater bioavailability, slow-release ability, and simultaneous P nutrient supplement. The findings highlight the importance of tuning of nanomaterial morphology and composition to optimize sustainability and efficacy.

Zein nanoparticles (ZNPs) are proposed as effective delivery systems capable of enhancing the translocation of nonsystemic agrochemicals from the roots to the leaves of soybean plants. ZNPs with entrapped methoxyfenozide (MFZ) (209.0 ± 5.6 nm and −42.1 ± 2.1 mV) were formed via emulsion-evaporation and used to facilitate the translocation of MFZ from the roots to the leaves and stems, as measured by liquid chromatography-mass spectrometry (LC-MS), under hydroponic conditions. MFZ concentration increased within the leaves over time from 0.04 to 2.35 μg g–1at 0.2 mg mL–1ZNPs exposure, compared to free MFZ (<0.02 μg g–1) after 24 h of exposure. The MFZ release from ZNPs, as measured by high-performance liquid chromatography (HPLC), followed pseudo-first-order kinetics at 25 °C, with a faster release at lower ZNP concentrations than at higher concentrations. ZNPs may prove to be a versatile delivery system for other agrochemicals due to their ability to enhance translocation within plants.

Matricaria chamomillaflowers were incubated with gold nanoparticles of different sizes ranging from 1.4 to 94 nm. After different incubation times of 6, 12, 24, and 48 h, the gold distribution in the flowers was destructively measured by inductively coupled plasma mass spectrometry (ICP-MS) and non-destructively measured by X-ray fluorescence imaging (XFI) with high lateral resolution. As a control, the biodistribution of iodine ions or iodine-containing organic molecules (iohexol) was determined, in order to demonstrate the feasibility of mapping the distribution of several elements in parallel. The results show a clear size-dependent transport of the nanoparticles. In addition, the surface chemistry also plays a decisive role in disposition. Only the 1.6 nm nanoparticles coated with acetylcysteine could be efficiently transported through the stem of the flowers into the petals. In this case, almost 80% of the nanoparticles which were found within each flower were located in the petals. The study also highlights the potential of XFI for in siturecording of in vivoanalyte biodistribution.

The inefficient delivery of agrichemicals in agrifood systems is among the leading cause of serious negative planetary and public health impacts. Such inefficiency is mainly attributed to the inability to deliver the agrichemicals at the right place (target), right time, and right dose. In this study, scalable, biodegradable, sustainable, biopolymer-based multistimuli responsive core–shell nanostructures were developed for smart agrichemical delivery. Three types of responsive core/shell nanostructures incorporated with model agrichemicals (i.e., CuSO4and NPK fertilizer) were synthesized by coaxial electrospray, and the resulting nanostructures showed spherical morphology with an average diameter about 160 nm. Tunable agrichemical release kinetics were achieved by controlling the surface hydrophobicity of nanostructures. The pH and enzyme responsiveness was also demonstrated by the model analyte release kinetics (up to 7 days) in aqueous solution. Finally, the efficacy of the stimuli responsive nanostructures was evaluated in soil-based greenhouse studies using soybean and wheat in terms of photosynthesis efficacy and linear electron flow (LEF), two important metrics for seedling development and health. Findings confirmed plant specificity; for soybean, the nanostructures resulted in 34.3% higher value of relative chlorophyll content and 41.2% higher value of PS1 centers in photosystem I than the ionic control with equivalent agrichemical concentration. For wheat, the nanostructures resulted in 37.6% higher value of LEF than the ionic agrichemicals applied at 4 times higher concentration, indicating that the responsive core–shell nanostructure is an effective platform to achieve precision agrichemical delivery while minimizing inputs. Moreover, the Zn and Na content in the leaves of 4-week-old soybean seedlings were significantly increased with nanostructure amendment, indicating that the developed nanostructures can potentially be used to modulate the accumulation of other important micronutrients through a potential biofortification strategy.

Sustainable strategies for the management of iron deficiency in agriculture are warranted because of the low use efficiency of commercial iron fertilizer, which confounds global food security and induces negative environmental consequences. The impact of foliar application of differently sized γ-Fe2O3nanomaterials (NMs, 4–15, 8–30, and 40–215 nm) on the growth and physiology of soybean seedlings was investigated at different concentrations (10–100 mg/L). Importantly, the beneficial effects on soybean were size- and concentration-dependent. Foliar application with the smallest size γ-Fe2O3NMs (S-Fe2O3NMs, 4–15 nm, 30 mg/L) yielded the greatest growth promotion, significantly increasing the shoot and nodule biomass by 55.4 and 99.0%, respectively, which is 2.0- and 2.6-fold greater than the commercially available iron fertilizer (EDTA-Fe) with equivalent molar Fe. In addition, S-Fe2O3NMs significantly enhanced soybean nitrogen fixation by 13.2% beyond that of EDTA-Fe. Mechanistically, transcriptomic and metabolomic analyses revealed that (1) S-Fe2O3NMs increased carbon assimilation in nodules to supply more energy for nitrogen fixation; (2) S-Fe2O3NMs activated the antioxidative system in nodules, with subsequent elimination of excess reactive oxygen species; (3) S-Fe2O3NMs up-regulated the synthesis of cytokinin and down-regulated ethylene and jasmonic acid content in nodules, promoting nodule development and delaying nodule senescence. S-Fe2O3NMs also improved 13.7% of the soybean yield and promoted the nutritional quality (e.g., free amino acid content) of the seeds as compared with EDTA-Fe with an equivalent Fe dose. Our findings demonstrate the significant potential of γ-Fe2O3NMs as a high-efficiency and sustainable crop fertilizer strategy.

Achieving sustainable agricultural productivity and global food security are two of the biggest challenges of the new millennium. Addressing these challenges requires innovative technologies that can uplift global food production, while minimizing collateral environmental damage and preserving the resilience of agroecosystems against a rapidly changing climate. Nanomaterials with the ability to encapsulate and deliver pesticidal active ingredients (AIs) in a responsive (for example, controlled, targeted and synchronized) manner offer new opportunities to increase pesticidal efficacy and efficiency when compared with conventional pesticides. Here, we provide a comprehensive analysis of the key properties of nanopesticides in controlling agricultural pests for crop enhancement compared with their non-nanoscale analogues. Our analysis shows that when compared with non-nanoscale pesticides, the overall efficacy of nanopesticides against target organisms is 31.5% higher, including an 18.9% increased efficacy in field trials. Notably, the toxicity of nanopesticides toward non-target organisms is 43.1% lower, highlighting a decrease in collateral damage to the environment. The premature loss of AIs prior to reaching target organisms is reduced by 41.4%, paired with a 22.1% lower leaching potential of AIs in soils. Nanopesticides also render other benefits, including enhanced foliar adhesion, improved crop yield and quality, and a responsive nanoscale delivery platform of AIs to mitigate various pressing biotic and abiotic stresses (for example, heat, drought and salinity). Nonetheless, the uncertainties associated with the adverse effects of some nanopesticides are not well-understood, requiring further investigations. Overall, our findings show that nanopesticides are potentially more efficient, sustainable and resilient with lower adverse environmental impacts than their conventional analogues. These benefits, if harnessed appropriately, can promote higher crop yields and thus contribute towards sustainable agriculture and global food security.

The exogenous application of nanoscale biochar has great potential in agriculture to improve crop resistance to pathogens, although the mechanisms underlying this physiological response are unclear. We investigated the potential of nanoscale and conventional biochar amendment to induce resistance in Nicotiana benthamianaupon infection with the pathogen Phytophthora nicotianae. Nanoscale biochar synthesized at 350 °C (400 mg L−1) from corn straw with a particle size of ∼160 nm had a beneficial role in the active immunity of N. benthamianathrough the ethylene pathway to provide resistance to P. nicotianaeinfection; in leaf assays, lesion diameters were reduced by 9.26% as compared to controls. Mechanistically, a 20.3% increase in reactive oxygen species (ROS) from biochar NP amendment activated the ethylene pathway, followed by SA-induced systemic acquired resistance (SAR) expression. The SA-induced immunity increased over 10-fold in the two biochar NP treatments. In addition, the biochar NPs induced PR1-ato a significantly greater extent than did regular biochar particles. In an experiment with the plant elicitor 5-methoxyindole, biochar NPs served as a unique delivery platform to improve plant growth, over 105.3% in the shoot length and 41.2% in the root length after seed treatment with biochar NPs and 5-methoxyindole compared to the untreated controls. This study demonstrates the successful use of exogenous nanoscale biochar amendment to stimulate plant defense responses and subsequent resistance to the important pathogen P. nicotianae. This approach holds great promise as a new plant protection strategy in sustainable nano-enabled agriculture.

Physico-chemical characteristics of engineered nanomaterials are known to be important in determining the impact on organisms but effects are equally dependent upon the characteristics of the organism exposed. Species sensitivity may vary by orders of magnitude, which could be due to differences in the type or magnitude of the biochemical response, exposure or uptake of nanomaterials. Synthesizing conclusions across studies and species is difficult as multiple species are not often included in a study, and differences in batches of nanomaterials, the exposure duration and media across experiments confound comparisons. Here three model species, Danio rerio, Daphnia magnaand Chironomus riparius, that differ in sensitivity to lithium cobalt oxide nanosheets are found to differ in immune-response, iron–sulfur protein and central nervous system pathways, among others. Nanomaterial uptake and dissolution does not fully explain cross-species differences. This comparison provides insight into how biomolecular responses across species relate to the varying sensitivity to nanomaterials.

Here, we conducted a life-cycle study with rice grown in soil amended with different concentrations (0, 1 and 10 mg kg−1) of silver nanoparticles (AgNPs) for 120 days. A lower dose of AgNPs promoted rice tillering, resulting in a significant increase in grain yield (42.3%) and aerial biomass (19.7%) compared to an untreated control, while a higher dose of AgNPs significantly decreased grain yield (26.4%) and biomass (28.1%). Inductively coupled plasma-mass spectrometry (ICP-MS) data reveal that Ag was accumulated in roots and translocated into shoots. Importantly, Ag was detected in the rice seeds, but was primarily located in rice hull and bran, not reaching edible tissues (polished rice), suggesting a low dietary risk to human health. Gas chromatography-mass spectrometry (GC-MS) based metabolomics show that 1 mg kg−1AgNPs altered the grain metabolome, increasing the abundance of functional metabolites (naproxen, benzyl alcohol, and metharbital) and decreasing several primary metabolites (TCA cycle intermediates). In rice grains, the content of Fe and Mo was significantly decreased by 24.7% and 31.8%, respectively, upon exposure to 1 mg kg−1AgNPs, indicating a trade-off between grain yield and mineral nutrient content. In addition, AgNPs at 1 mg kg−1caused a significant increase (1.2–2.3 fold) in several putative plant-beneficial taxa, inlcuding Frankiales, Rhizobiales, Chitinophagales, and Saccharimonadia.Taken together, these results show that AgNPs at 1 mg kg−1are generally beneficial to plants and associated soil microbes, although additional work on material properties and amendment regimen is needed to optimize the agricultural benefits and minimize potential negative consequences on grain nutrient content.

Coriander (Coriandrum sativumL.) seedlings were cultivated in 50% Hoagland's nutrient solution amended with carbon dots (CDs) at different concentrations (0, 10, 20, 30 and 40 mg L−1) for 7 days to mechanistically explore impacts on carbohydrate, protein, vitamin C, and mineral nutrient content in the edible tissues. Amendment with 40 mg L−1CDs increased the soluble sugar and protein content in coriander leaves by 17.0 and 27.1% in comparison with controls, respectively. Also, 30 and 40 mg L−1CDs significantly increased the vitamin C content in coriander leaves by 22.8 and 26.0%, respectively. These increases are likely due to CDs promotion of photosynthesis. Further investigation revealed that CDs treatment increased chlorophyll content, rubisco activity, and photosystem II (PSII) activity by accelerating the electron transfer rate. Furthermore, in coriander shoots, CDs at 30 mg L−1significantly increased K and Mn content by 25.7 and 16.3%, respectively. CDs at 40 mg L−1increased the content of K by 64.3%, Ca by 21.0%, Mg by 26.2%, P by 12.8%, Mn by 56.0% and Fe by 125%, relative to untreated controls; these increases appear to be related to an increased transpiration rate with CDs amendment. Antioxidant response analysis revealed that CDs enhance plant stress resistance, which also benefits plant growth and productivity. These findings show that CDs promote photosynthesis and the uptake of essential elements, thereby improving crop nutritional quality, and may be a novel nano-enabled strategy to increase agricultural production.

The present study investigated the mechanisms by which large- and small-sized nanoscale hydroxyapatite (nHA) suppressed Fusarium-induced wilt disease in tomato. Both nHA sizes at 9.3 mg/L (low) and 46.5 mg/L (high dose) phosphorus (P) were foliar-sprayed on Fusarium-infected tomato leaf surfaces three times. Diseased shoot mass was increased by 40% upon exposure to the low dose of large-sized nHA compared to disease controls. Exposure to both nHA sizes significantly elevated phenylalanine ammonialyase activity and total phenolic content in Fusarium-infected shoots by 30–80% and 40–68%, respectively. Shoot salicylic acid content was also increased by 10–45%, suggesting the potential relationship between antioxidant and phytohormone pathways in nHA-promoted defense against fungal infection. Exposure to the high dose of both nHA sizes increased the root P content by 27–46%. A constrained analysis of principal coordinates suggests that high dose of both nHA sizes significantly altered the fatty acid profile in diseased tomato. Particularly, the diseased root C18:3 content was increased by 28–31% in the large-sized nHA treatments, indicating that nHA remodeled the cell membrane as part of defense against Fusariuminfection. Taken together, our findings demonstrate the important role of nHA in promoting disease suppression for the sustainable use of nHA in nanoenabled agriculture.

The use of nanotechnology to suppress crop diseases has attracted increasing attention in agriculture. The present work investigated the antifungal efficacy of copper oxide nanoparticle (CuO NP)-embedded hydrogels, which were synthesized by loading CuO nanoparticles (NPs) in hydrogels formed from cross-linked interaction between chitosan and acrylic acid, against Fusarium wilt of lettuce (Lactuca sativa) caused by Fusarium oxysporumf. sp. lactucae. In comparison with CuO NPs, 7-day Cu dissolution from CuO NP-embedded hydrogels was 34.2–94.8% slower regardless of media type, including water, potato dextrose broth, or a soil extract. In a greenhouse study, upon exposure to CuO NP-embedded hydrogels, CuO NPs, or Kocide 3000 with equivalent amounts of Cu (31 mg/kg), the fresh shoot biomass was significantly increased by 40.5, 26.1 and 27.2%, respectively, as compared to that of the infected control. Notably, CuO NP-embedded hydrogels enhanced uptake of P, Mn, Zn, and Mg and increased the levels of organic acids as compared to the diseased control. Increased salicylic acid (SA) and decreased jasmonic acid (JA) and abscisic acid (ABA) levels with the addition of different forms of Cu may have enhanced disease resistance. Taken together, our findings provide useful information and approach for improving the delivery efficiency of agrichemicals via nanoenabled strategies and an advanced understanding of plant defense mechanisms triggered by Cu-based NPs.

In this study, spinach plants exposed to fresh/unweathered (UW) or weathered (W) copper compounds in soil were analyzed for growth and nutritional composition. Plants were exposed for 45 days to freshly prepared or soil-aged (35 days) nanoparticulate CuO (nCuO), bulk-scale CuO (bCuO), or CuSO4at 0 (control), 400, 400, and 40 mg/kg of soil, respectively. Foliar health, gas exchange, pigment content (chlorophyll and carotenoid), catalase and ascorbate peroxidase enzymes, gene expression, and Cu bioaccumulation were evaluated along with SEM imagery for select samples. Foliar biomass was higher in UW control (84%) and in UW ionic treatment (87%), compared to the corresponding W treatments (p≤ 0.1). Root catalase activity was increased by 110% in UW bCuO treatment as compared to the W counterpart; the value for the W ionic treatment was increased by 2167% compared to the UW counterpart (p≤ 0.05). At 20 days post-transplantation, W nCuO-exposed plants had ∼56% lower carotenoid content compared to both W control and the UW counterpart (p≤ 0.05). The findings indicate that over the full life cycle of spinach plant the weathering process significantly deteriorates leaf pigment production under CuO exposure in particular and foliar health in general.

Rice is known to accumulate arsenic (As) in its grains, posing serious health concerns for billions of people globally. We studied the effect of nanoscale sulfur (NS) on rice seedlings and mature plants under As stress. NS application caused a 40% increase in seedling biomass and a 26% increase in seed yield of mature plants compared to untreated control plants. AsIII exposure caused severe toxicity to rice; however, coexposure of plants to AsIII and NS alleviated As toxicity, and growth was significantly improved. Rice seedlings treated with AsIII + NS produced 159 and 248% more shoot and root biomass, respectively, compared to plants exposed to AsIII alone. Further, AsIII + NS-treated seedlings accumulated 32 and 11% less As in root and shoot tissues, respectively, than the AsIII-alone treatment. Mature plants treated with AsIII + NS produced 76, 110, and 108% more dry shoot biomass, seed number, and seed yield, respectively, and accumulated 69, 38, 18, and 54% less total As in the root, shoot, flag leaves, and grains, respectively, compared to AsIII-alone-treated plants. A similar trend was observed in seedlings treated with AsV and NS. The ability of sulfur (S) to alleviate As toxicity and accumulation is clearly size dependent as NS could effectively reduce bioavailability and accumulation of As in rice via modulating the gene expression activity of As transport, S assimilatory, and glutathione synthesis pathways to facilitate AsIII detoxification. These results have significant environmental implications as NS application in agriculture has the potential to decrease As in the food chain and simultaneously enable crops to grow and produce higher yields on marginal and contaminated lands.

Although phosphorus (P) is an essential element, its availability to plants is often limited, and P-containing fertilizers must be supplemented to stimulate plant performance. However, the inefficiencies and negative environmental impacts associated with current nutrient delivery strategies have motivated interest in nanotechnology-enabled agriculture. Here, we synthesized biodegradable polymer nanocomposites (PNCs) containing polyhydroxyalkanoate (PHA) and calcium phosphate nanoparticles (Ca–P–NPs) and assessed their efficacy as a P-delivery vehicle, compared to a conventional P source (CaHPO4), using tomato as a test plant. The effectiveness of PHA–Ca–P PNCs was assessed by measuring plant biomass, fruit yield and quality, tissue elemental and chlorophyll content, and enzymatic biomarkers. Phosphorus in the leachate was used as a surrogate for runoff. PHA–Ca–P PNCs biodegraded as a result of microbial activity in the soil, controlling the release of P during the initial stages of plant growth. PHA–Ca–P PNCs supported plant performance comparably to the conventional P source, while significantly reducing the P loss from the soil by over 80%. Given the negative consequences of eutrophication driven by P-rich agricultural runoff, this significant reduction in lost P has broad implications. Our studies also highlight the need to improve the efficiency of P uptake by plants from exogenous P sources. Collectively, these findings demonstrate the significant potential of biodegradable PNCs as a nutrient delivery platform to simultaneously enhance crop productivity and reduce the negative impacts of agriculture on the environment.

Micronutrients applied as nanoparticles of metal oxides have shown efficacy in vegetable and other crops for improving yield and reducing Fusarium diseases, but their role in ornamental crop management has not been investigated. In 2017, 2018, and 2020, nanoparticles of CuO, Mn2O3, or ZnO were foliarly applied at 500 μg/mL (0.6 mg/plant) to chrysanthemum transplants and planted in potting soil noninfested or infested with Fusarium oxysporumf. sp. chrysanthemi. An untreated control and a commercial fungicide, Fludioxonil, was also included. Chrysanthemums treated with nanoscale CuO had a 55, 30, and 32% reduction in disease severity ratings compared to untreated plants in 2017, 2018, and 2020, respectively. Specifically, the average dry biomass for the three years was reduced 22% by disease, but treatment with nanoscale CuO led to a 23% increase when compared to controls. Similar trends with plant height were observed. Horticultural quality was improved 28% with nano CuO and was equal to the fungicide. Nanoscale Mn2O3and the fungicide did not consistently reduce disease ratings or increase dry biomass each year. Nanoscale ZnO was ineffective. Nanoscale CuO-treated plants had 24 to 48% more Cu/g tissue than controls (P< 0.001). These findings agree with past reports on food crops where single applications of nanoscale CuO improved plant health, growth, and yield and could offer significant impacts for managing plant diseases on ornamentals.