Nanotechnology has emerged as a transformative field in agriculture, offering innovative solutions to enhance plant growth and resilience against abiotic stresses. This review explores the diverse applications of nanomaterials in agriculture, focusing on their role in promoting plant development and improving tolerance to drought, salinity, heavy metals, and temperature fluctuations. The method classifies nanomaterials commonly employed in plant sciences and examines their unique physicochemical properties that facilitate interactions with plants. Key mechanisms of nanomaterial uptake, transport, and influence on plants at the cellular and molecular levels are outlined, emphasizing their effects on nutrient absorption, photosynthetic efficiency, and overall biomass production. The molecular basis of stress tolerance is examined, highlighting nanomaterial-induced regulation of reactive oxygen species, antioxidant activity, gene expression, and hormonal balance. Furthermore, this review addresses the environmental and health implications of nanomaterials, emphasizing sustainable and eco-friendly approaches to mitigate potential risks. The integration of nanotechnology with precision agriculture and smart technologies promises to revolutionize agricultural practices. This review provides valuable insights into the future directions of nanomaterial R&D, paving the way for a more resilient and sustainable agricultural system.

Heat stress caused by global warming adversely affects wheat yield through declining most nutritional quality attributes in grains, excluding grain protein content.

This research investigated the biochemical, physiological, and antioxidant responses of wheat plants under heat stress, focusing on the role of plant growth-promoting bacteria (Micromonospora sp.). Two wheat genotypes were studied: one heat-sensitive and one heat-tolerant, examining their responses to heat stress with and without bacterial inoculation.

Under heat stress, the sensitive cultivar experienced significant reductions in photosynthesis rate, chlorophyll content, and RuBisCO activity (57-61%), while the tolerant cultivar had milder reductions (24-28%). Micromonospora sp. treatment notably improved these parameters in the sensitive cultivar (+48-78%), resulting in a substantial increase in biomass production (+43-53%), which was not seen in the tolerant cultivar. Additionally, oxidative stress markers (H2O2 and MDA) were elevated more in the sensitive cultivar (82% and 90% higher) compared to the tolerant one. Micromonospora sp. treatment effectively reduced these markers in the sensitive cultivar (-28% and -27%). Enhanced activity of antioxidant enzymes and ASC-GSH pathway enzymes was particularly evident in Micromonospora sp.-treated sensitive plants. Carbohydrate metabolism shifted, with increased soluble sugars and significant rises in sucrose content in Micromonospora sp.-treated plants under stress.

The higher soluble sugar levels facilitated amino acid synthesis, contributing to biosynthesis of secondary metabolites, including flavonoids, polyphenols, and anthocyanins. This was reflected in increased activity of phenylalanine ammonia-lyase, cinnamate (CA) 4-hydroxylase, and chalcone synthase enzymes, indicating the activation of phenylpropanoid pathways. Overall, the findings suggest that Micromonospora sp. can mitigate heat stress effects by enhancing photosynthetic efficiency, antioxidant defense, and metabolic adaptations in heat-sensitive wheat cultivars.

The integration of nanotechnology in agriculture offers a transformative approach to improving crop yields, resource efficiency, and ecological sustainability. This review highlights the application of functional NM, such as nano-formulated agrochemicals, nanosensors, and slow-release fertilizers, which enhance the effectiveness of fertilizers and pesticides while minimizing environmental impacts. By leveraging the unique properties of NM, agricultural practices can achieve better nutrient absorption, reduced chemical runoff, and improved water conservation. Innovations like nano-priming can enhance seed germination and drought resilience, while nanosensors enable precise monitoring of soil and crop health. Despite the promising commercial potential, significant challenges persist regarding the safety, ecological impact, and regulatory frameworks for nanomaterial use. This review emphasizes the need for comprehensive safety assessments and standardized risk evaluation protocols to ensure the responsible implementation of nanotechnology in agriculture.

The mung bean crop (Vigna radiata (L.) R. Wilczek) is widely recognized as a key source of pulse food worldwide. However, this crop suffers substantial yield losses due to humid environments, particularly from infestations by the fungal pathogen Macrophomina phaseolina, which causes charcoal rot disease. This infestation results in significant agronomic losses, affecting both the crop's growth characteristics and overall yield. Previous research suggests that these losses can be mitigated through environmentally friendly soil amendments, such as biochar, as well as by applying various nanofungicides. This study aims to explore the potential of biochar and zinc oxide nanoparticles (ZnONPs) to reduce the severity of charcoal rot disease and enhance the agronomic traits and yield of mung bean plants affected by this disease. The experiment was conducted in triplicate, applying ZnONPs at three concentrations (5, 10, and 20 mg. L- 1) via foliar spraying, combined with two levels of biochar (20 g and 40 g per pot). Positive and negative control treatments were also included for comparison. The results demonstrated that applying 40 g of biochar per pot and 20 mg. L- 1 of foliar-applied ZnONPs increased the activities of the anti-oxidative defence enzymes. Additionally, this treatment strategy boosted the plants' disease resistance mechanisms, leading to lower mortality rates and reduced levels of malondialdehyde (MDA) and hydrogen peroxide (H₂O₂) by 61.7% and 49.23%. Moreover, the treatment positively impacted key growth parameters, increasing total chlorophyll content by 43%, plant height by 47%, and legume count per plant by 80.4%. The application of biochar and ZnONPs also improved seed protein content, reflecting an enhancement in nutritional quality. This study supports the use of biochar and ZnONPs as biostimulants to manage yield losses in mung bean crops affected by charcoal rot disease. The future prospects of using ZnONPs and biochar as treatments in agriculture are promising, as they offer innovative, eco-friendly solutions to enhance crop productivity, improve soil health, and reduce reliance on synthetic chemicals, paving the way for more sustainable and resilient agricultural systems.

At the dawn of new millennium, policy makers and researchers focused on sustainable agricultural growth, aiming for food security and enhanced food quality. Several emerging scientific innovations hold the promise to meet the future challenges. Nanotechnology presents a promising avenue to tackle the diverse challenges in agriculture. By leveraging nanomaterials, including nano fertilizers, pesticides, and sensors, it provides targeted delivery methods, enhancing efficacy in both crop production and protection. This integration of nanotechnology with agriculture introduces innovations like disease diagnostics, improved nutrient uptake in plants, and advanced delivery systems for agrochemicals. These precision-based approaches not only optimize resource utilization but also reduce environmental impact, aligning well with sustainability objectives. Concurrently, genetic innovations, including genome editing and advanced breeding techniques, enable the development of crops with improved yield, resilience, and nutritional content. The emergence of precision gene-editing technologies, exemplified by CRISPR/Cas9, can transform the realm of genetic modification and enabled precise manipulation of plant genomes while avoiding the incorporation of external DNAs. Integration of nanotechnology and genetic innovations in agriculture presents a transformative approach. Leveraging nanoparticles for targeted genetic modifications, nanosensors for early plant health monitoring, and precision nanomaterials for controlled delivery of inputs offers a sustainable pathway towards enhanced crop productivity, resource efficiency, and food safety throughout the agricultural lifecycle. This comprehensive review outlines the pivotal role of nanotechnology in precision agriculture, emphasizing soil health improvement, stress resilience against biotic and abiotic factors, environmental sustainability, and genetic engineering.

In this study, the impact of zinc oxide nanoparticles (ZnO-NPs) generated using rosemary extract, synthesized using environmentally friendly processes and integrated into a cross-linked polymer matrix, on growth performance of wheat is evaluated. Rosemary extract used as coating, stabilizing, and reducing agents in this green synthesis method. Fourier transform infrared spectroscopy analyses demonstrated the presence of phytochemical constituents of the plant extract that served as capping agents during the synthesis process. The nanoparticles are sprayed to the plant leaves. The effects of nanoparticles within the hydrogel on plant development are compared with the effects of nanoparticles in suspension. The percentage of seed germination is unaffected by either rosemary- or raw-ZnO-NPs; however, the root and shoot elongation are considerably impacted by the nanoparticle treatments. The threshold concentrations are determined as 3000 mg L-1 for rosemary-ZnO-NPs and 2000 mg L-1 for raw-ZnO-NPs. Additionally, antibacterial test results showed that the activity level on Escherichia coli is higher for rosemary-ZnO-NPs compared to raw-ZnO-NPs. The results of this research may provide guidance on how green synthesis methods and the use of nanoparticle-hydrogel composites in plant breeding can be used in future agricultural applications. This can be considered an important step in terms of agricultural innovations and sustainability.

In response to global agricultural challenges, this review examines the synergistic impact of bioslurry and biogenic nanoparticles on soil amelioration. Bioslurry, rich in N, P, K and beneficial microorganisms, combined with zinc oxide nanoparticles synthesized through eco-friendly methods, demonstrates remarkable soil improvement capabilities. Their synergistic effects include enhanced nutrient availability through increased soil enzymatic activities, improved soil structure via stable aggregate formation, stimulated microbial activity particularly beneficial groups, enhanced water retention due to increased organic matter and modified soil surface properties and reduced soil pH fluctuations. These mechanisms significantly impact soil physico-chemical properties including cation exchange capacity, electrical conductivity and nutrient dynamics. This review analyses these effects and their implications for sustainable agricultural practices, focusing on crop yield improvements, reduced chemical fertilizer dependence and enhanced plant stress tolerance. Knowledge gaps such as long-term nanoparticle accumulation effects and impacts on non-target organisms are identified. Future research directions include optimizing bioslurry-nanoparticle ratios for various soil types and developing "smart" nanoparticle-enabled biofertilizers with controlled release properties. This innovative approach contributes to environmentally friendly farming practices, potentially enhancing global food security and supporting sustainable agriculture transitions. The integration of bioslurry and biogenic nanoparticles presents a promising solution to soil degradation and agricultural sustainability challenges.

Lactation women, a highly concerned demographic in society, face health risks that deserve attention. Zinc oxide nanoparticles (ZnO NPs) are widely utilized in food and daily products due to their excellent physicochemical properties, leading to the potential exposure of lactating women to ZnO NPs. Hence, assessing the potential risks associated with ZnO NP exposure during lactation is critical. While studies have confirmed that exposure to ZnO NPs during lactation can induce toxic responses in multiple organs through blood circulation, the effects of lactational exposure on mammary tissue remain unclear. This research investigated the impairment of mammary tissue induced by ZnO NPs and its potential mechanisms. Through administering multiple injections of ZnO NPs into the tail vein of lactating ICR mice, our study revealed that ZnO NPs can deposit in the mammary tissues, downregulating key components of mammary epithelial barrier such as ZO-1, occludin, and claudin-3. In vivo, we also found that ZnO NPs can simultaneously induce apoptosis, necroptosis, and pyroptosis, called PANoptosis. Additionally, using EpH4-Ev cells to simulate an in vitro mammary epithelial barrier model, we observed that ZnO NPs effectively disrupted the integrity of mammary epithelial barrier and induced PANoptosis. Furthermore, we confirmed that PANoptosis was responsible for the mammary epithelial barrier disruption induced by ZnO NPs. Moreover, we identified that ZBP1 was the primary mechanism of ZnO NPs inducing PANoptosis. These discoveries are designed to enhance our comprehension of the mechanisms underlying mammary epithelial barrier disruption caused by ZnO NPs, and we aim to highlight the potential hazards associated with daily usage and therapeutic exposure to ZnO NPs during lactation.

The soil is a vital resource that hosts many microorganisms crucial in biogeochemical cycles and ecosystem health. However, human activities such as the use of metal nanoparticles (MNPs), pesticides and the impacts of global climate change (GCCh) can significantly affect soil microbial communities (SMC). For many years, pesticides and, more recently, nanoparticles have contributed to sustainable agriculture to ensure continuous food production to sustain the significant growth of the world population and, therefore, the demand for food. Pesticides have a recognized pest control capacity. On the other hand, nanoparticles have demonstrated a high ability to improve water and nutrient retention, promote plant growth, and control pests. However, it has been reported that their accumulation in agricultural soils can also adversely affect the environment and soil microbial health. In addition, climate change, with its variations in temperature and extreme water conditions, can lead to drought and increased soil salinity, modifying both soil conditions and the composition and function of microbial communities. Abiotic stressors can interact and synergistically or additively affect soil microorganisms, significantly impacting soil functioning and the capacity to provide ecosystem services. Therefore, this work reviewed the current scientific literature to understand how multiple stressors interact and affect the SMC. In addition, the importance of molecular tools such as metagenomics, metatranscriptomics, proteomics, or metabolomics in the study of the responses of SMC to exposure to multiple abiotic stressors was examined. Future research directions were also proposed, focusing on exploring the complex interactions between stressors and their long-term effects and developing strategies for sustainable soil management. These efforts will contribute to the preservation of soil health and the promotion of sustainable agricultural practices.

Nanotechnology holds revolutionary potential in the field of agriculture, with zinc oxide nanoparticles (ZnO NPs) demonstrating advantages in promoting crop growth. Enhanced photosynthetic efficiency is closely linked to improved vigor and superior quality in tea plants, complemented by the beneficial role of phyllosphere microorganisms in maintaining plant health. However, the effects of ZnO NPs on the photosynthesis of tea plants, the sprouting of new shoots, and the community of phyllosphere microorganisms have not been fully investigated.

This study investigated the photosynthetic physiological parameters of tea plants under the influence of ZnO NPs, the content of key photosynthetic enzymes such as RubisCO, chlorophyll content, chlorophyll fluorescence parameters, transcriptomic and extensive targeted metabolomic profiles of leaves and new shoots, mineral element composition in these tissues, and the epiphytic and endophytic microbial communities within the phyllosphere. The results indicated that ZnO NPs could enhance the photosynthesis of tea plants, upregulate the expression of some genes related to photosynthesis, increase the accumulation of photosynthetic products, promote the development of new shoots, and alter the content of various mineral elements in the leaves and new shoots of tea plants. Furthermore, the application of ZnO NPs was observed to favorably influence the microbial community structure within the phyllosphere of tea plants. This shift in microbial community dynamics suggests a potential for ZnO NPs to contribute to plant health and productivity by modulating the phyllosphere microbiome.

This study demonstrates that ZnO NPs have a positive impact on the photosynthesis of tea plants, the sprouting of new shoots, and the community of phyllosphere microorganisms, which can improve the growth condition of tea plants. These findings provide new scientific evidence for the application of ZnO NPs in sustainable agricultural development and contribute to advancing research in nanobiotechnology aimed at enhancing crop yield and quality.

A slight variation in ecological milieu of plants, like drought, heavy metal toxicity, abrupt changes in temperature, flood, and salt stress disturbs the usual homeostasis or metabolism in plants. Among these stresses, salinity stress is particularly detrimental to the plants, leading to toxic effects and reduce crop productivity. In a saline environment, the accumulation of sodium and chloride ions up to toxic levels significantly correlates with intracellular osmotic pressure, and can result in morphological, physiological, and molecular alterations in plants. Increased soil salinity triggers salt stress signals that activate various cellular-subcellular mechanisms in plants to enable their survival in saline conditions. Plants can adapt saline conditions by maintaining ion homeostasis, activating osmotic stress pathways, modulating phytohormone signaling, regulating cytoskeleton dynamics, and maintaining cell wall integrity. To address ionic toxicity, researchers from diverse disciplines have explored novel approaches to support plant growth and enhance their resilience. One such approach is the application of nanoparticles as a foliar spray or seed priming agents positively improve the crop quality and yield by activating germination enzymes, maintaining reactive oxygen species homeostasis, promoting synthesis of compatible solutes, stimulating antioxidant defense mechanisms, and facilitating the formation of aquaporins in seeds and root cells for efficient water absorption under various abiotic stresses. Thus, the assessment mainly targets to provide an outline of the impact of salinity stress on plant metabolism and the resistance strategies employed by plants. Additionally, the review also summarized recent research efforts exploring the innovative applications of zinc oxide nanoparticles for reducing salt stress at biochemical, physiological, and molecular levels.

The underlying mechanisms through which silicon oxide nanoparticles (SiNPs) can confer salinity resistance to plants are poorly understood. This study explored the efficacy of supplementing nutrient solution with SiNPs (20-30 nm; 10 mg kg-1 soil) to stimulate metabolism and alleviate the risks associated with salinity (0.73 g kg-1 soil) in basil seedlings. For this purpose, variations in photosynthetic indices, proline osmoprotectant, antioxidant markers, phenylpropanoid metabolism, and transcriptional behaviors of genes were investigated. SiNPs increased shoot fresh weight (38%) and mitigated the risk associated with the salinity stress by 14%. SiNPs alleviated the inhibitory effects of salinity on the total chlorophyll concentration by 15%. The highest increase (twofold) in proline content was recorded in the SiNP-treated seedlings grown under salinity. The nano-supplement enhanced the activity of enzymatic antioxidants, including peroxidase (2.5-fold) and catalase (4.7-fold). SiNPs induced the expression of gamma-cadinene synthase (CDS) and caffeic acid O-methyltransferase (COMT) genes by 6.5- and 18.3-fold, respectively. SiNPs upregulated the eugenol synthase (EGS1) and fenchol synthase (FES) genes by six- and nine-fold, respectively. Salinity transcriptionally downregulated the geraniol synthase (GES) gene, while this gene displayed an upward trend in response to SiNPs by eight-fold. The nano-supplement transcriptionally stimulated the R-linalool synthase (LIS) gene by 3.3-fold. The terpinolene synthase (TES) gene displayed a similar trend to that of the GES gene. The highest expression (25-fold) of the phenylalanine ammonia-lyase (PAL) gene was recorded in seedlings supplemented with SiNPs. The physiological and molecular assessments demonstrated that employing SiNPs is a sustainable strategy for improving plant primary/secondary metabolism and crop protection.

The extensive utilization of zinc oxide nanoparticles in consumer products and the industry has led to their substantial entry into the soil through air and surface runoff transportation, which causes ecotoxicity in agro-ecosystems and detrimental effects on crop production. Nanobubbles (diameter size < 1 µm) have many advantages, such as a high surface area, rapid mass transfer, and long retention time. In this study, wheat seedlings were irrigated with a 500 mg L-1 zinc oxide nanoparticle solution delivered in the form of nanobubble watering (nanobubble-ZnO-NPs). We found that nanobubble watering improved the growth and nutrient status of wheat exposed to zinc oxide nanoparticles, as evidenced by increased total foliar nitrogen and phosphorus, along with enhanced leaf dry mass per area. This effect can be attributed to nanobubbles disassembling zinc oxide aggregates formed due to soil organic carbon, thereby mitigating nutrient absorption limitations in plants. Furthermore, nanobubbles improved the capability of soil oxygen input, leading to increased root activity and glycolysis efficiency in wheat roots. This work provides valuable insights into the influence of nanobubble watering on soil quality and crop production and offers an innovative approach for agricultural irrigation that enhances the effectiveness and efficiency of water application.

Triclosan has been extensively used as a preservative in cosmetics and personal care products. However, its accumulation represents a real environmental threat. Thus, its phytotoxic impact needs more consideration. Our study was conducted to highlight the phytotoxic effect of triclosan on the growth, ROS homeostasis, and detoxification metabolism of two different plant species i.e., legumes (Glycine max) and grass (Avena sativa). Moreover, we investigated the potentiality of plant growth-promoting bacteria (ST-PGPB) in mitigating the phytotoxic effect of triclosan. Triclosan induced biomass (fresh and dry weights) reduction in both plants, but to a higher extent in oats. This decline was associated with a noticeable increment in the oxidative damage (e.g., MDA and H2O2) and detoxification metabolites such as metallothionein (MTC), phytochelatins (PCs), and glutathione-S-transferase (GST). This elevation was associated with a remarkable reduction in both enzymatic and non-enzymatic antioxidants. On the other hand, the bioactive strain of ST-PGPB, Salinicoccus sp. JzA1 significantly alleviated the harmful effect of triclosan on both soybean and oat plants by enhancing their biomass, photosynthesis, as well as levels of minerals (K, Ca, P, Mn, and Zn). In parallel, a striking quenching in oxidative damage and an obvious improvement in non-enzymatic (polyphenols, tocopherols, flavonoids) and enzymatic antioxidants were observed. Furthermore, Salinicoccus sp. JzA1 augmented the detoxification metabolism by enhancing the levels of phytochelatins, metallothionein, and glutathione-S-transferase (GST) activity in a species-specific manner which is more apparent in soybean rather than in oat plants. To this end, stress mitigating impact of Salinicoccus sp. JzA1 provides a basis to improve the resilience of crop species under cosmetics and personal care products toxicity.

Engineered nanomaterials (ENMs) are inevitably released into the environment with the exponential application of nanotechnology. Parts of ENMs eventually accumulate in the soil environment leading to potential adverse effects on soil ecology, crop production, and human health. Therefore, the safety application of ENMs on soil has been widely discussed in recent years. More detailed safety information and potential soil environmental risks are urgently needed. However, most of the studies on the environmental effects of metal-based ENMs have been limited to single-species experiments, ecosystem processes, or abiotic processes. The present review formulated the source and the behaviors of the ENMs in soil, and the potential effects of single and co-exposure ENMs on soil microorganisms, soil fauna, and plants were introduced. The toxicity mechanism of ENMs to soil organisms was also reviewed including oxidative stress, the release of toxic metal ions, and physical contact. Soil properties affect the transport, transformation, and toxicity of ENMs. Toxic mechanisms of ENMs include oxidative stress, ion release, and physical contact. Joint toxic effects occur through adsorption, photodegradation, and loading. Besides, future research should focus on the toxic effects of ENMs at the food chain levels, the effects of ENMs on plant whole-lifecycle, and the co-exposure and long-term toxicity effects. A fast and accurate toxicity evaluation system and model method are urgently needed to solve the current difficulties. It is of great significance for the sustainable development of ENMs to provide the theoretical basis for the ecological risk assessment and environmental management of ENMs.

The escalating release of zinc oxide nanoparticles (ZnO NPs) into the environment poses a substantial threat, potentially leading to increased concentrations of zinc (Zn) in the soil and subsequent phytotoxic effects. This study aimed to assess the effects of ZnO NPs on Raphanus sativus (R. sativus) concerning its tolerance levels, toxicity, and accumulation. ZnO NPs were synthesized by the wet chemical method and characterized by powder X-ray diffraction (PXRD), Fourier-transform infrared (FTIR) spectroscopy, ultraviolet-visible (UV-vis) spectroscopy, dynamic light scattering (DLS), and scanning electron microscopy (SEM). The effect of ZnO NPs (70 nm) on R. sativus grown in coir was evaluated. The application of 1,000 mg/L of ZnO NPs resulted in a significant increase (p < 0.05) in soluble protein content, carbohydrates, chlorophyll a (Chl-a), chlorophyll b (Chl-b), total chlorophylls, carotenoids, and antioxidants by 24.7%, 58.5%, 38.0%, 42.2%, 39.9%, 11.2%, and 7.7%, respectively. Interestingly, this dose had no impact on the indole acetic acid (IAA) content. Conversely, the use of 2,000 mg/L of ZnO NPs in the same medium led to a significant reduction (p < 0.05) in soluble protein content by 23.1%, accompanied by a notable increase in IAA by 31.1%, indicating potential toxicity. The use of atomic absorption spectroscopy confirmed the internalization of zinc in seedlings, with a statistically significant increase (p < 0.05). In control plants without ZnO NPs, Zn concentration was 0.36 mg/g, while at the highest ZnO NPs tested dose of 10,000 mg/L, it significantly rose to 1.76 mg/g, causing leaf chlorosis and stunted seedling growth. This suggests potential health risks related to Zn toxicity for consumers. Given the adverse effects on R. sativus at concentrations above 1000 mg/L, caution is advised in the application and release of ZnO NPs, highlighting the importance of responsible practices to mitigate harm to plant life and consumer health. The study demonstrated the tolerance of R. sativus to high Zn levels, classifying it as a Zn-tolerant species.

Cadmium stress is a major threat to plant growth and survival worldwide. The current study aims to green synthesis, characterization, and application of zinc-oxide nanoparticles to alleviate cadmium stress in maize (Zea mays L.) plants. In this experiment, two cadmium levels (0, 0.6 mM) were applied to check the impact on plant growth attributes, chlorophyll contents, and concentration of various primary metabolites and antioxidants under exogenous treatment of zinc-oxide nanoparticles (25 and 50 mg L-1) in maize seedlings. Tissue sampling was made 21 days after the zinc-oxide nanoparticles application. Our results showed that applying cadmium significantly reduced total chlorophyll and carotenoid contents by 52.87% and 23.31% compared to non-stress. In comparison, it was increased by 53.23%, 68.49% and 9.73%, 37.53% with zinc-oxide nanoparticles 25, 50 mg L-1 application compared with cadmium stress conditions, respectively. At the same time, proline, superoxide dismutase, peroxidase, catalase, and ascorbate peroxidase contents were enhanced in plants treated with cadmium compared to non-treated plants with no foliar application, while it was increased by 12.99 and 23.09%, 23.52 and 35.12%, 27.53 and 36.43%, 14.19 and 24.46%, 14.64 and 37.68% by applying 25 and 50 mg L-1 of zinc-oxide nanoparticles dosages, respectively. In addition, cadmium toxicity also enhanced stress indicators such as malondialdehyde, hydrogen peroxide, and non-enzymatic antioxidants in plant leaves. Overall, the exogenous application of zinc-oxide nanoparticles (25 and 50 mg L-1) significantly alleviated cadmium toxicity in maize. It provides the first evidence that zinc-oxide nanoparticles 25 ~ 50 mg L-1 can be a candidate agricultural strategy for mitigating cadmium stress in cadmium-polluted soils for safe agriculture practice.

The current investigation aimed at evaluating the impact of Azadirachta indica-mediated zinc oxide nanoparticles (Ai-ZnONPs) on the growth and biochemical characteristics of maize (sweet glutinous 3000) under exposure to 50 mg kg-1Ai-ZnONPs with Cr (VI) concentrations of 50 and 100 mg kg-1. The results indicate that plants exposed to Cr (VI) only experienced a decline in growth parameters. Conversely, the inclusion of Ai-ZnONPs caused a noteworthy increase in physiological traits. Specifically, shoot and root fresh weight increased by 28.02% and 16.51%, and 63.11% and 97.91%, respectively, when compared to Cr-50 and 100 treatments. Additionally, the SPAD chlorophyll of the shoot increased by 91.08% and 15.38% compared to Cr-50 and 100 treatments, respectively. Moreover, the antioxidant enzyme traits of plant shoot and root, such as superoxide dismutase (SOD 7.44% and 2.70%, and 4.45% and 3.53%), catalase (CAT 1.18% and 3.20%, and 5.03% and 5.78%), and peroxidase (POD 0.31% and 5.55%, and 4.72% and 3.61%), exhibited significant increases in Cr 50 and 100 treatments, respectively. The addition of Ai-ZnONPs to the soil also enhanced soil nutrient status and reduced Cr (VI) concentrations by 40.69% and 19.82% compared to Cr-50 and 100 treated soils. These findings suggest that Ai-ZnONPs can trigger the activation of biochemical pathways that enable biomass accumulation in meristematic cells. Further investigations are required to elucidate the mechanisms involved in growth promotion.

Fungal and bacterial pathogens represent some of the greatest challenges facing crop production globally and account for about 20-40 % crop losses annually. This review highlights the use of ZnO NPs as antimicrobial agents and explores their mechanisms of actions against disease causing plant fungal pathogens. The behavior of ZnO NPs in soil and their interactions with the soil components were also highlighted. The review discusses the potential effects of ZnO NPs on plants and their mechanisms of action on plants and how these mechanisms are related to their physicochemical properties. In addition, the reduction of ZnO NPs toxicity through surface modification and coating with silica is also addressed. Soil properties play a significant role in the dispersal, aggregation, stability, bioavailability, and transport of ZnO NPs and their release into the soil. The transport of ZnO NPs into the soil might influence soil components and, as a result, plant physiology. The harmful effects of ZnO NPs on plants and fungi are caused by a variety of processes, the most important of which is the formation of reactive oxygen species, lysosomal instability, DNA damage, and the reduction of oxidative stress by direct penetration/liberation of Zn2+ ions in plant/fungal cells. Based on these highlighted areas, this review concludes that ZnO NPs exhibit its antifungal activity via generations of reactive oxygen species, coupled with the inhibition of various metabolic pathways. Despite the numerous advantages of ZnO NPs, there is need to regulate its uses to minimize the harmful effects that may arise from its applications in the soil and plants.

Zinc oxide nanoparticles (ZnO NPs) have been widely used in agriculture as a new type of Zn fertilizer, and many studies were conducted to evaluate the effect of ZnO NPs on plant growth. However, there are relatively few studies on the effects of application methods and appropriate dosages of ZnO NPs on rice yield, quality, grain Zn content, and distribution. Therefore, in the 2019 and 2020, field trials were conducted with six ZnO NPs basal application dosages of no ZnO NPs, 3.75 kg hm-2, 7.5 kg hm-2, 15 kg hm-2, 30 kg hm-2, and 60 kg hm-2, and the effects of ZnO NPs application on rice yield, quality, grain Zn content, and distribution were investigated. The results demonstrated that applying ZnO NPs in Zn-deficient soils (available Zn < 1.0 mg kg-1) increased rice grain yield by 3.24%-4.86% and 3.51%-5.12% in 2019 and 2020, respectively. In addition, ZnO NPs improved the quality of rice by increasing the head milling rate, reducing chalky grain percentage, and increasing the taste value and breakdown of rice. In terms of Zn accumulation in rice, ZnO NPs application significantly increased the Zn content in both milled rice and brown rice, compared with no Zn treatment, in 2019 and 2020, Zn content in milled rice significantly increased by 20.46%-41.09% and 18.11%-38.84%, respectively, and in brown rice significantly increased by 25.78%-48.30% and 20.86%-42.00%, respectively. However, the Zn fertilizer utilization gradually decreased with increasing ZnO NPs application dosage. From the perspective of yield, rice quality, Zn fertilizer utilization, and Zn accumulation, basal application of 7.5 kg-30 kg hm-2 ZnO NPs is beneficial for rice yield and quality improvement and rice Zn accumulation. This study effectively demonstrated that ZnO NPs could be a potential high-performed fertilizer for enhancing rice yield, quality, and zinc content of edible grain fraction synergistically.

In this study, zinc and copper oxide nanoparticles (NPs) were synthesized using hemp (Cannabis sativa L.) leaves (ZnONP-HL and CuONP-HL), and their antifungal potential was assessed against Fusarium virguliforme in soybean (Glycine max L.). Hemp was selected because it is known to contain large quantities of secondary metabolites that can potentially enhance the reactivity of NPs through surface property modification. Synthesizing NPs with biologically derived materials allows to avoid the use of harsh and expensive synthetic reducing and capping agents. The ZnONP-HL and CuONP-HL showed average grain/crystallite size of 13.51 nm and 7.36 nm, respectively. The biologically synthesized NPs compared well with their chemically synthesized counterparts (ZnONP chem, and CuONP chem; 18.75 nm and 10.05 nm, respectively), confirming the stabilizing role of hemp-derived biomolecules. Analysis of the hemp leaf extract and functional groups that were associated with ZnONP-HL and CuONP-HL confirmed the presence of terpenes, flavonoids, and phenolic compounds. Biosynthesized NPs were applied on soybeans as bio-nano-fungicides against F. virguliforme via foliar treatments. ZnONP-HL and CuONP-HL at 200 μg/mL significantly (p < 0.05) increased (∼ 50%) soybean growth, compared to diseased controls. The NPs improved the nutrient (e.g., K, Ca, P) content and enhanced photosynthetic indicators of the plants by 100-200%. A 300% increase in the expression of soybean pathogenesis related GmPR genes encoding antifungal and defense proteins confirmed that the biosynthesized NPs enhanced disease resistance against the fungal phytopathogen. The findings from this study provide novel evidence of systemic suppression of fungal disease by nanobiopesticides, via promoting plant defense mechanisms.

Zinc (Zn) deficiency has caused nutritional disorders in 17% of the world's population; thus, producing Zn-enriched plants as a dietary source is necessary. Recently, nanofertilizers have gained much attention as a substitute for conventional fertilizers; however, soil application of polymer-coated Zn-based nanofertilizer has not been explored much. The present study depicts the green synthesis of ZnO nanoparticles using Melia azedarach L. leaf extract, whose phytoconstituents have reducing abilities. The synthesized nanoparticles were combined with gum acacia (GA) to form a ZnOGA nanocomposite. The structural and morphological properties of ZnOGA were studied using XRD, FTIR, FESEM, and EDX. A pot experiment study was carried out with Spinacia oleracea L. at various doses (3, 5, and 10 mg/kg) of the synthesized ZnOGA to evaluate its effectiveness as a slow-release fertilizer and was compared with a commercial Zn fertilizer. The plant growth studies revealed a significant increase in the phyto-morphological traits of the plants fertilized with ZnOGA compared to commercial fertilizer. The plants also displayed significantly higher contents of protein (17-47%), phenols (25-60%), proline (82-94%), total soluble sugar (20-31%), DPPH activity (70-72%), and Zn uptake (91-106%). The doses of ZnOGA played an imperative role in determining the growth and productivity of the plant. Soil column studies showed that ZnOGA reduces Zn leaching by 52% compared to commercial Zn fertilizer. This study signifies the potential of ZnOGA to be applied as an eco-friendly and sustainable substitute for conventional Zn fertilizer minimizing Zn losses and Zn deficiency-related health problems in human populations.

This study aimed to assess the effect of zinc oxide nanoparticles (ZNPs) and/or arsenic trioxide (ATO) exposure on the liver of adult male Sprague Dawley rats. Moreover, the probable ameliorative impact of gallic acid (GA) against ZNPs and ATO-induced hepatotoxicity and the possible underlying mechanisms were evaluated.

Sixty male Sprague Dawley rats were distributed into six groups. The 1^st and 2^nd groups were orally given distilled water (1 ml/kg) and 20 mg GA/kg b. wt, respectively. The 3^rd and 4^th groups were orally given 100 mg ZNPs/kg b. wt and 8 mg ATO/kg b. wt, respectively. The 5^th group was co-administered ZNPs and ATO at the doses mentioned above. The last one was co-administered ZNPs, ATO, and GA at the earlier described doses. All tested compounds were orally given once a day for 60 successive days. Then, serum levels of alkaline phosphatase (ALP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), total, direct, indirect bilirubin, triglycerides, total cholesterol, HDL, VLDL, and LDL were estimated. The hepatic content of malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GPx) was evaluated. Moreover, Bcl-2 and Bax's reactive proteins were immunohistochemically detected, and Zn and As residual patterns in hepatic tissues were assessed.

ZNPs, ATO, and ZNPs+ATO-exposed rats showed significantly (P < 0.001) elevated serum AST (219%, 233%, and 333%), ALT (300%, 400%, and 475%), ALP (169%, 205%, and 294%), and total bilirubin (42%, 68%, and 109%) compared to the control ones. On the other hand, a significantly (P < 0.001) declined SOD (58%, 49%, and 43%) and GPx (70%, 63%, and 56%) but increased MDA (133%, 150%, and 224%) was recorded in the hepatic tissues of ZNPs, ATO, and ZNPs+ATO exposed rats, respectively, relative to the control rats. Moreover, the hepatic tissues of the ZNPs, ATO, and ZNPs+ATO exposed rats showed a significant (P < 0.001) decrease in Bcl-2 (28%, 33%, and 23%) but elevation in Bax (217%, 267%, and 236%) immunoreactivities compared to the control rats. These findings were consistent with the microscopic alterations in the hepatic architecture and accumulation of Zn and As. Furthermore, a notable hyperlipidemic condition was recorded following ZNPs and/or ATO exposure. On the contrary, GA notably reduced hepatic enzymes compared to ZNPs+ATO-exposed rats. Additionally, GA markedly improved ZNPs+ATO-afforded liver tissue damage and apoptotic events.

Overall, GA oral dosing significantly mitigated the negative effects of ZNPs and ATO on the liver by improving the antioxidant defense system and controlling apoptotic changes.

In this study, a soil culture and a hydroponic experiment were conducted to assess the toxicology effects of copper oxide nanoparticles (CuO NPs) on soil microbial community structure and the growth of bok choy. Results showed CuO NPs had an inhibitory effect on soil microbial abundance, diversity, and activity, as well as the bok choy seedling growth, whereas CuO NPs at low concentrations did not significantly affect the soil microbial biomass or plant growth. In soil, CuO NPs at high dose (80 mg kg^-1) significantly reduced the indexes of Simpson diversity, Shannon-Wiener diversity and Pielou evenness by 3.7%, 4.9% and 4.5%, respectively. In addition, CuO NPs at 20 and 80 mg kg^-1 treatment significantly reduced soil enzymes (urease, alkaline phosphatase, dehydrogenase, and catalase) activities by 25.5%-58.9%. Further, CuO NPs at 20 mg L^-1 significantly inhibited the growth of plant root by 33.8%, and catalase (CAT) activity by 17.9% in bok choy seedlings. The present study can provide a basis for a comprehensive evaluation of the toxicity effect of CuO NPs on soil microorganisms and phytotoxicity to bok choy seedlings.

Agricultural industry is facing huge crisis due to fast changing climate, decreased soil fertility, macro and micronutrient insufficiency, misuse of chemical fertilizers and pesticides, and heavy metal presence in soil. With exponential increase in world's population, food consumption has increased significantly. Maintaining the production to consumption ratio is a significant challenge due to shortage caused by various issues faced by agricultural industry even with the improved agricultural practices. Recent scientific evidence suggests that nanotechnology can positively impact the agriculture sector by reducing the harmful effects of farming operations on human health and nature, as well as improving food productivity and security. Farmers are combining improved agricultural practices like usage of fertilizers, pesticides etc. with nano-based materials to improve the efficiency and productivity of crops. Nano technology is also playing a significant role improving animal health products, food packaging materials, and nanosensors for detecting pathogens, toxins, and heavy metals in soil among others. The nanobased materials have improved the productivity twice with half the resources being utilized. Nanoparticles that are currently in use include titanium dioxide, zinc oxide, silicon oxide, magnesium oxide, gold, and silver used for increasing soil fertility and plant growth. Crop growth, yield, and productivity are improved by controlled release nanofertilizers. In this review we elaborate on the recent developments in the agricultural sector by the usage of nanomaterial based composites which has significantly improved the agricultural sector especially how nanoparticles play an important role in plant growth and soil fertility, in controlling plant diseases by the use of nanopesticides, nanoinsecticides, nanofertilizers, Nanoherbicides, nanobionics, nanobiosensors. The review also highlights the mechanism of migration of nanoparticles in plants and most importantly the effects of nanoparticles in causing plant and soil toxicity.

Soil secondary salinization is a serious menace that has significant influence on the sustainability of agriculture and threatens food security around the world. Zinc (Zn) as an essential plant nutrient associated with many physio-biochemical processes in plants and improve resistance against various abiotic stresses. The role of Zn in acclimation of Solanum lycopersicum L. challenged with salt stress is miserly understood. A hydroponic study was performed with two tomato varieties (Riogrande and Sungold) exposed to the salinity stress (0 mM and 160 mM NaCl) under two Zn concentrations (15 μM and 30 μM ZnSO₄). The results revealed that salt stress exerted strongly negative impacts on root and shoot length, fresh and dry biomass, plant water relations, membrane stability, chlorophyll contents, Na⁺/K⁺ ratio along with inferior gas exchange attributes and activities of antioxidant enzymes. Moreover, Riogrande was found to be more resistant to salinity stress than Sungold. However, Zn supply significantly alleviated the hazardous effects of salinity by altering compatible solutes accumulation, photosynthetic activity, water relation, soluble sugar contents and providing antioxidant defense against salt stress. The salinity + Zn2 treatment more obviously enhanced RWC (19.0%), MSI (30.8%), SPAD value (17.8%), and activities of SOD (31.7%), POD (28.5%), APX (64.5%) and CAT (23.3%) in Riogrande than Sungold, compared with the corresponding salinity treatment alone. In addition, salinity + Zn2 treatment significantly (P > 0.05) ameliorated salinity stress due to the depreciation in Na⁺/K⁺ ratio by 63.3% and 40.8%, Na⁺ ion relocation from root to shoot by 10.4% and 6.4%, and thereby significantly reduced Na⁺ ion accumulation by 47.4% and 16.3% in the leaves of Riogrande and Sungold respectively, compared to the salinity treatment alone. Therefore, it was obvious that 30 μM Zn concentration was more effective to induce resistance against salinity stress than 15 μM Zn concentration. Conclusively, it can be reported that exogenous Zn application helps tomato plant to combat adverse saline conditions by modulating photosynthetic and antioxidant capacity along with reduced Na⁺ uptake at the root surface of tomato plant.

Organic pesticides are major sources of soil pollution in agricultural lands. Most of these pesticides are persistent and tend to bio accumulate in humans upon consumption of contaminated plants. In this study, we investigate different natural soil samples that were collected from agricultural lands. The samples revealed the presence of 18 pesticides that belong to four different groups including organochlorines (OCP), organophosphorus (OPP), carbamates (Carb), and pyrethroids (Pyrth). The photocatalytic degradation of the five most abundant pesticides was studied in the presence and absence of 1% TiO2 or ZnO photocatalysts under UV irradiation at a wavelength of 306 nm. The five abundant pesticides were Atrazine (OCP), Chlorpyrifos methyl (OPP), Dimethoate (OPP), Heptachlor (OCP), and Methomyl (Carb). The results showed that photolysis of all pesticides was complete under UV radiation for irradiation times between 64-100 h. However, both photocatalysts enhanced photocatalytic degradation of the pesticides in comparison with photolysis. The pesticides were photocatalytically degraded completely within 20-24 h of irradiation. The TiO2 photocatalyst showed higher activity compared to ZnO. The organochlorine heptachlor, which is very toxic and persistent, was completely degraded within 30 h using TiO2 photocatalyst for the first time in soil. The mechanism of photocatalytic degradation of the pesticides was explained and the effects of different factors on the degradation process in the soil were discussed.