Engineered nanoparticles are materials between 1 and 100 nm and exist as metalloids, metallic oxides, nonmetals, and carbon nanomaterials and as functionalized dendrimers, liposomes, and quantum ...dots. Their small size, large surface area, and high reactivity have enabled their use as bactericides fungicides and nanofertilizers. Nanoparticles can be designed as biosensors for plant disease diagnostics and as delivery vehicles for genetic material, probes, and agrichemicals. In the past decade, reports of nanotechnology in phytopathology have grown exponentially. Nanomaterials have been integrated into disease management strategies and diagnostics and as molecular tools. Most reports summarized herein are directed toward pathogen inhibition using metalloid metallic oxide nanoparticles as bactericides fungicides and as nanofertilizers to enhance health. The use of nanoparticles as biosensors in plant disease diagnostics is also reviewed. As global demand for food production escalates against a changing climate, nanotechnology could sustainably mitigate many challenges in disease management by reducing chemical inputs and promoting rapid detection of pathogens.
Various nano-enabled strategies are proposed to improve crop production and meet the growing global demands for food, feed and fuel while practising sustainable agriculture. After providing a brief ...overview of the challenges faced in the sector of crop nutrition and protection, this Review presents the possible applications of nanotechnology in this area. We also consider performance data from patents and unpublished sources so as to define the scope of what can be realistically achieved. In addition to being an industry with a narrow profit margin, agricultural businesses have inherent constraints that must be carefully considered and that include existing (or future) regulations, as well as public perception and acceptance. Directions are also identified to guide future research and establish objectives that promote the responsible and sustainable development of nanotechnology in the agri-business sector.
Nanotechnology could make agriculture more efficient and more sustainable, but more systematic understanding of the mechanisms involved is necessary to prove the potential of nano-enabled ...agrochemicals.
Novel versatile nanomaterials may facilitate strategies for simultaneous soil remediation and agricultural production, but a thorough and mechanistic assessment of efficacy and safety is needed. We ...have established a new soil remediation strategy using nanoscale zero-valent iron (nZVI) coupled with safe rice production in paddy soil contaminated with pentachlorophenol (PCP). In comparison with rice cultivation in contaminated soil with 100 mg PCP per kg soil but without nZVI, the addition of 100 mg nZVI per kg soil increased grain yield by 47.1-55.0%, decreased grain PCP content by 83.6-86.2% and increased the soil PCP removal rate from 49.9 to 83.9-89.0%. The specific role of nZVI-derived root iron plaque formation in the safe production of rice has been elucidated, and the synergistic effect of nZVI treatment and rice cultivation identified in the nZVI-facilitated rhizosphere microbial degradation of PCP. This work opens a new strategy for the application of nanomaterials in soil remediation that could simultaneously enable safe crop production in contaminated lands.
Graphene-family nanomaterials (GFNs) including pristine graphene, reduced graphene oxide (rGO) and graphene oxide (GO) offer great application potential, leading to the possibility of their release ...into aquatic environments. Upon exposure, graphene/rGO and GO exhibit different adsorption properties toward environmental adsorbates, thus the molecular interactions at the GFN–water interface are discussed. After solute adsorption, the dispersion/aggregation behaviors of GFNs can be altered by solution chemistry, as well as by the presence of colloidal particles and biocolloids. GO has different dispersion performance from pristine graphene and rGO, which is further demonstrated from surface properties. Upon exposure in aquatic environments, GFNs have adverse impacts on aquatic organisms (e.g., bacteria, algae, plants, invertebrates, and fish). The mechanisms of GFNs toxicity at the cellular level are reviewed and the remaining unclear points on toxic mechanisms such as membrane damage are presented. Moreover, we highlight the transformation routes of GO to rGO. The degradation of GFNs upon exposure to UV irradiation and/or biota is also reviewed. In view of the unanswered questions, future research should include comprehensive characterization of GFNs, new approaches for explaining GFNs aggregation, environmental behaviors of metastable GO, and the relationship between dispersion of GFNs and the related adsorption properties.
The potential risks from metal-based nanoparticles (NPs) in the environment have increased with the rapidly rising demand for and use of nanoenabled consumer products. Plant’s central roles in ...ecosystem function and food chain integrity ensure intimate contact with water and soil systems, both of which are considered sinks for NPs accumulation. In this review, we document phytotoxicity caused by metal-based NPs exposure at physiological, biochemical, and molecular levels. Although the exact mechanisms of plant defense against nanotoxicity are unclear, several relevant studies have been recently published. Possible detoxification pathways that might enable plant resistance to oxidative stress and facilitate NPs detoxification are reviewed herein. Given the importance of understanding the effects and implications of metal-based NPs on plants, future research should focus on the following: (1) addressing key knowledge gaps in understanding molecular and biochemical responses of plants to NPs stress through global transcriptome, proteome, and metablome assays; (2) designing long-term experiments under field conditions at realistic exposure concentrations to investigate the impact of metal-based NPs on edible crops and the resulting implications to the food chain and to human health; and (3) establishing an impact assessment to evaluate the effects of metal-based NPs on plants with regard to ecosystem structure and function.
Although nanomaterials (NMs) may inhibit viral pathogens, the mechanisms governing plant–virus–nanomaterial interactions remain unknown. Nicotiana benthamiana plants were treated with nanoscale ...titanium dioxide (TiO2) and silver (Ag), C60 fullerenes, and carbon nanotubes (CNTs) at 100, 200 and 500 mg L−1 for a 21-day foliar exposure before inoculation with GFP-tagged tobacco mosaic virus (TMV). Plants treated with CNTs and C60 (200 mg L−1) exhibited normal phenotype and viral symptomology was not evident at 5 days post-infection. TiO2 and Ag failed to suppress viral infection. RT-qPCR analysis revealed that viral coat protein transcript abundance and GFP mRNA expression were reduced 74–81% upon CNTs and C60 treatment. TEM revealed that the chloroplast ultrastructure in carbon NM-treated plants was unaffected by TMV infection. Fluorescence measurement of CNTs and C60 (200 mg L−1) treated plants indicated photosynthesis equivalent to healthy controls. CNTs and C60 induced upregulation of the defense-related phytohormones abscisic acid and salicylic acid by 33–52%; the transcription of genes responsible for phytohormone biosynthesis was elevated by 94–104% in treated plants. Our findings demonstrate the protective role of carbon-based NMs, with suppression of TMV symptoms via hindered physical movement and viral replication. Given the lack of viral phytopathogen treatment options, this work represents a novel area of nano-enabled agriculture.
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•Current study reveals the mechanisms governing plant–virus–nanomaterial interactions.•Carbon-based NMs play a protective role against single-stranded RNA TMV.•Early foliar exposure of carbon-based NMs at 200 mg L−1 inhibits TMV replication and systemic infection of apical tissues.•NMs augment the plant’s immunity by improving photosynthetic performance and triggering defense responses against TMV.
Engineered nanomaterials (ENMs) have huge potential for improving use efficiency of agrochemicals, crop production, and soil health; however, the behavior and fate of ENMs and the potential for ...negative long‐term impacts to agroecosystems remain largely unknown. In particular, there is a lack of clear understanding of the transformation of ENMs in both soil and plant compartments. The transformation can be physical, chemical, and/or biological, and may occur in soil, at the plant interface, and/or inside the plant. Due to these highly dynamic processes, ENMs may acquire new properties distinct from their original profile; as such, the behavior, fate, and biological effects may also differ significantly. Several essential questions in terms of ENMs transformation are discussed, including the drivers and locations of ENM transformation in the soil–plant system and the effects of ENM transformation on analyte uptake, translocation, and toxicity. The main knowledge gaps in this area are highlighted and future research needs are outlined so as to ensure sustainable nanoenabled agricultural applications.
Transformation of engineered nanomaterials (ENMs) determines their environmental fate and impacts. Several essential questions including the drivers and locations of ENM transformation in the soil–plant system and the effects of ENMs transformation on their uptake, translocation, and toxicity are discussed. The main knowledge gaps in this area are highlighted and future research needs are outlined so as to ensure sustainable nanoenabled agricultural applications.
CuO nanoparticles (NPs) (20, 50 mg L–1) inhibited seedling growth of different Arabidopsis thaliana ecotypes (Col-0, Bay-0, and Ws-2), as well as the germination of their pollens and harvested seeds. ...For most of growth parameters (e.g., biomass, relative growth rate, root morphology change), Col-0 was the more sensitive ecotype to CuO NPs compared to Bay-0 and Ws-2. Equivalent Cu2+ ions and CuO bulk particles had no effect on Arabidopsis growth. After CuO NPs (50 mg L–1) exposure, Cu was detected in the roots, leaves, flowers and harvested seeds of Arabidopsis, and its contents were significantly higher than that in CuO bulk particles (50 mg L–1) and Cu2+ ions (0.15 mg L–1) treatments. Based on X-ray absorption near-edge spectroscopy analysis (XANES), Cu in the harvested seeds was confirmed as being mainly in the form of CuO (88.8%), which is the first observation on the presence of CuO NPs in the plant progeny. Moreover, after CuO NPs exposure, two differentially expressed genes (C-1 and C-3) that regulated root growth and reactive oxygen species generation were identified, which correlated well with the physiological root inhibition and oxidative stress data. This current study provides direct evidence for the negative effects of CuO NPs on Arabidopsis, including accumulation and parent-progeny transfer of the particles, which may have significant implications with regard to the risk of NPs to food safety and security.
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