Prospects of Nanotechnology in Improving the Productivity and Quality of Horticultural Crops

Metallic nanoparticles unveiled: Synthesis, characterization, and their environmental, medicinal, and agricultural applications

Metallic nanoparticles (MNPs) have attracted great interest among scientists and researchers for years due to their unique optical, physiochemical, biological, and magnetic properties. As a result, MNPs have been widely utilized across a variety of scientific fields, including biomedicine, agriculture, electronics, food, cosmetics, and the environment. In this regard, the current review article offers a comprehensive overview of recent studies on the synthesis of MNPs (metal and metal oxide nanoparticles), outlining the benefits and drawbacks of chemical, physical, and biological methods. However, the biological synthesis of MNPs is of great importance considering the biocompatibility and biological activity of certain MNPs. A variety of characterization techniques, including X-ray diffraction, transmission electron microscopy, UV-visible spectroscopy, scanning electron microscopy, dynamic light scattering, atomic force microscopy, Fourier transform infrared spectroscopy, and others, have been discussed in depth to gain deeper insights into the unique structural and spectroscopic properties of MNPs. Furthermore, their unique properties and applications in the fields of medicine, agriculture, and the environment are summarized and deeply discussed. Finally, the main challenges and limitations of MNPs synthesis and applications, as well as their future prospects have also been discussed.

Heavy metals removal from industrial wastewater of Biskra (Algeria) by Arundo donax and Phragmites australis

Industrial effluents pose a serious environmental problem, because they contain toxic contaminants mainly heavy metals that are the most dangerous to humans, animals, plants, and the environment in general. Phytoremediation using macrophytes is an adopted technique for the environment decontamination due to its efficiency and cost-effectiveness. The present study aims to highlight the capabilities of macrophytes to remove heavy metals from wastewater of Biskra region (Algeria). The methodology consists of filling out the filters planted with Arundo donax and Phragmites australis with raw industrial wastewater, then recovering decontaminated water after 15 days to assess removal of lead, copper, zinc, and iron. Both plants had shown a good efficiency for the removal of metals loaded in wastewater eliminating about 94 to 98% of initial concentration. In addition, calculated bioaccumulation factor (BAF) had confirmed the accumulation of heavy metals in different parts of experimental plants; recorded values of BAF > 1 allowed the consideration of Arundo donax and Phragmites australis as good hyper-accumulator plants. Obtained results confirm the efficiency of phytoremediation technology using macrophytes for the wastewater treatment in particular and the environment decontamination in general.

Determination of pesticide residues in varieties of pepper sold at different periods and provinces in Turkey and investigation of their adverse effects on human health and the environment

Pesticides are dangerous chemicals that can harm to people and the environment when applied inappropriately or in excess. In this research, various pesticide residues were investigated in 48 pepper samples using liquid chromatography-tandem mass spectrometry (LC-MS/MS). All samples were collected randomly in two periods of time (September and December) from markets and greengrocers in four provinces (Siirt, Mardin, Diyarbakir, and Batman). Considering the means of the first and second periods, diclofop-methyl had the highest concentration of 29.4 ± 7.7 µg kg-1, and diazinon had the lowest of 21.1 ± 4.6 µg kg-1. Based on the maximum residue limits (MRLs) of pesticides specified in the Turkish Food Codex, pyrimethanil, bupirimate, and diclofop-methyl were found to be below the maximum acceptable residue limit, while pyridaphention, dinoseb, diazinon, and pirimiphos-methyl were found to be above the limit. Thus, the current study demonstrated the potential of LC-MS/MS as a crucial technique for accurate measurements and confirmations of pesticides in different pepper varieties.

Agriculture and environmental management through nanotechnology: Eco-friendly nanomaterial synthesis for soil-plant systems, food safety, and sustainability

Through the advancement of nanotechnology, agricultural and food systems are undergoing strategic enhancements, offering innovative solutions to complex problems. This scholarly essay thoroughly examines nanotechnological innovations and their implications within these critical industries. Traditional practices are undergoing radical transformation as nanomaterials emerge as novel agents in roles traditionally filled by fertilizers, pesticides, and biosensors. Micronutrient management and preservation techniques are further enhanced, indicating a shift towards more nutrient-dense and longevity-oriented food production. Nanoparticles (NPs), with their unique physicochemical properties, such as an extraordinary surface-to-volume ratio, find applications in healthcare, diagnostics, agriculture, and other fields. However, concerns about their potential overuse and bioaccumulation raise unanswered questions about their health effects. Molecule-to-molecule interactions and physicochemical dynamics create pathways through which nanoparticles cause toxicity. The combination of nanotechnology and environmental sustainability principles leads to the examination of green nanoparticle synthesis. The discourse extends to how nanomaterials penetrate biological systems, their applications, toxicological effects, and dissemination routes. Additionally, this examination delves into the ecological consequences of nanomaterial contamination in natural ecosystems. Employing robust risk assessment methodologies, including the risk allocation framework, is recommended to address potential dangers associated with nanotechnology integration. Establishing standardized, universally accepted guidelines for evaluating nanomaterial toxicity and protocols for nano-waste disposal is urged to ensure responsible stewardship of this transformative technology. In conclusion, the article summarizes global trends, persistent challenges, and emerging regulatory strategies shaping nanotechnology in agriculture and food science. Sustained, in-depth research is crucial to fully benefit from nanotechnology prospects for sustainable agriculture and food systems.

Horticulture crop under pressure: Unraveling the impact of climate change on nutrition and fruit cracking

Climate change is increasingly affecting the nutritional content and structural integrity of horticultural crops, leading to challenges such as diminished fruit quality and the exacerbation of fruit cracking. This manuscript systematically explores the multifaceted impacts of these changes, with a particular focus on the nutritional quality and increased incidence of fruit cracking. An exhaustive review of current research identifies the critical role of transcription factors in mediating plant responses to climatic stressors, such as drought, temperature extremes, and saline conditions. The significance of transcription factors, including bHLH, bZIP, DOF, MDP, HD-ZIP, MYB, and ERF4, is highlighted in the development of fruit cracking, underscoring the genetic underpinnings behind stress-related phenotypic outcomes. The effectiveness of greenhouse structures in mitigating adverse climatic effects is evaluated, offering a strategic approach to sustain crop productivity amidst CO2 fluctuations and water scarcity, which are shown to influence plant physiology and lead to changes in fruit development, nutrient dynamics, and a heightened risk of cracking. Moreover, the manuscript delves into advanced breeding strategies and genetic engineering techniques, such as genome editing, to enhance crop resilience against climatic challenges. It also discusses adaptation strategies vital for sustainable horticulture, emphasizing the need to integrate novel genetic insights with controlled environment horticulture to counteract climate change's detrimental effects. The synthesis presented here underscores the urgent need for innovative breeding strategies aimed at developing resilient crop varieties that can withstand climatic uncertainty while preserving nutritional integrity.

Nanotechnology for controlling mango malformation: a promising approach

Mango (Mangifera indica L.) is one of the most important fruit crops in the world with yields of approximately 40 million tons annually and its production continues to decrease every year as a result of the attack of certain pathogens i.e. Colletotrichum gloeosporioides, Erythricium salmonicolor, Amritodus atkinsoni, Idioscopus clypealis, Idioscopus nitidulus, Bactrocera obliqua, Bactrocera frauenfeldi, Xanthomonas campestris, and Fusarium mangiferae. So F. mangiferae is the most harmful pathogen that causes mango malformation disease in mango which decreases its 90% yield. Nanotechnology is an eco-friendly and has a promising effect over traditional methods to cure fungal diseases. Different nanoparticles possess antifungal potential in terms of controlling the fungal diseases in plants but applications of nanotechnology in plant disease managements is minimal. The main focus of this review is to highlight the previous and current strategies to control mango malformation and highlights the promising applications of nanomaterials in combating mango malformation. Hence, the present review aims to provide brief information on the disease and effective management strategies.Communicated by Ramaswamy H. Sarma.

Revolutionizing agriculture: Harnessing nano-innovations for sustainable farming and environmental preservation

The agricultural sector is currently confronted with a significant crisis stemming from the rapid changes in climate patterns, declining soil fertility, insufficient availability of essential macro and micronutrients, excessive reliance on chemical fertilizers and pesticides, and the presence of heavy metals in soil. These numerous challenges pose a considerable threat to the agriculture industry. Furthermore, the exponential growth of the global population has led to a substantial increase in food consumption, further straining agricultural systems worldwide. Nanotechnology holds great promise in revolutionizing the food and agriculture industry, decreasing the harmful effects of agricultural practices on the environment, and improving productivity. Nanomaterials such as inorganic, lipid, and polymeric nanoparticles have been developed for increasing productivity due to their unique properties. Various strategies can enhance product quality, such as the use of nano-clays, nano zeolites, and hydrogel-based materials to regulate water absorption and release, effectively mitigating water scarcity. The production of nanoparticles can be achieved through various methods, each of which has its own unique benefits and limitations. Among these methods, chemical synthesis is widely favored due to the impact that various factors such as concentration, particle size, and shape have on product quality and efficiency. This review provides a detailed examination of the roles of nanotechnology and nanoparticles in sustainable agriculture, including their synthetic methods, and presents an analysis of their associated advantages and disadvantages. To date, there are serious concerns and awareness about healthy agriculture and the production of healthy products, therefore the development of nanotech-enabled devices that act as preventive and early warning systems to identify health issues, offering remedial measures is necessary.

Encapsulated nanopesticides application in plant protection: Quo vadis?

The increased global food insecurity due to the growing population can be addressed with precision and sustainable agricultural practices. To tackle the issues regarding food insecurity, farmers used different agrochemicals that improved plant growth and protection. Among these agrochemicals, synthetic pesticides used for plant protection in the agricultural field have various disadvantages. Conventional applications of synthetic pesticides have drawbacks such as rapid degradation, poor solubility, and non-target effects, as well as increased pesticide runoff that pollutes the environment. Nanotechnology has evolved as a potential solution to increase agricultural productivity through the development of different nanoforms of agrochemicals such as nanopesticides, nano-fabricated fertilizers, nanocapsules, nanospheres, nanogels, nanofibers, nanomicelles, and nano-based growth promoters. Encapsulation of these pesticides inside the nanomaterials has provided good biocompatibility over conventional application by inhibiting the early degradation of active ingredients (AI), increasing the uptake and adhesion of pesticides, improving the stability, solubility, and permeability of the pesticides, and decreasing the environmental impacts due to the pesticide runoff. In this review, different nanoforms of encapsulated pesticides and their smart delivery systems; nanocarriers in RNA interference (RNAi) based pesticides; environmental fate, practical implications, management of nanopesticides; and future perspectives are discussed.

Nanotechnology and CRISPR/Cas9 system for sustainable agriculture

The clustered regularly interspaced short palindromic repeats (CRISPR-Cas9), a genome editing tool, has gained a tremendous position due to its therapeutic efficacy, ability to counteract abiotic/biotic stresses in plants, environmental remediation and sustainable agriculture with the aim of food security. This is mainly due to their potential of precised genome modification and numerous genetic engineering protocols with versatility as well as simplicity. This technique is quite useful for crop refinement and overcoming the agricultural losses and regaining the soil fertility hampered by hazardous chemicals. Since CRISPR/Cas9 has been widely accepted in genome editing in plants, however, their revolutionised nature and progress enable genetic engineers to face numerous challenges in plant biotechnology. Therefore, nanoparticles have addressed these challenges and improved cargo delivery and genomic editing processes. Henceforth, this barrier prevents CRISPR-based genetic engineering in plants in order to show efficacy in full potential and eliminate all the barriers. This advancement accelerates the genome editing process and its applications in plant biotechnology enable us to sustain and feed the massive population under varying environments. Genome editing tools using CRISPR/Cas9 and nanotechnology are advantageous that produce transgenic-free plants that overcome global food demands. Here, in this review, we have aimed towards the mechanisms/delivery systems linked with CRISPR/Cas9 system. We have elaborated on the applications of CRISPR/Cas9 and nanotechnology-based systems for sustainable agriculture. Moreover, the challenges and limitations associated with genome editing and delivery systems have also been discussed with a special emphasis on crop improvement.

Recent Trends in Foliar Nanofertilizers: A Review

It is estimated that 40-70%, 80-90% and 50-90% of the conventional macronutrients N, P and K applied to the soil are lost, respectively, resulting in considerable loss of resources. Compared to conventional fertilizers, nanofertilizers have the advantages of controlled release, high nutrient utilization, low cost and relatively low environmental pollution due to their small size (1-100 nm) and high specific surface area. The application of nanofertilizers is an up-and-coming field of agricultural research and is an attractive and economical substitute for common fertilizers which can boost global food productivity sustainably. Foliar fertilization is a popular way to satisfy the needs of higher plants. Because of its small application dose, faster nutrient uptake than soil application and relatively less environmental pollution, foliar fertilization is more popular among plants. It can be seen that nanofertilizers and foliar fertilization are the hotspots of attention at present and that current research on the foliar application of nanofertilizers is not as extensive as that on soil application. Based on this background, this paper provides an overview of various applications of foliar spraying of nanofertilizers in agriculture, including applications in improving crop yield and quality as well as mitigating heavy metal stress, salt stress and drought stress.

Siddique K, Li B. Nanobiotechnology to advance stress resilience in plants: Current opportunities and challenges

A sustainable and resilient crop production system is essential to meet the global food demands. Traditional chemical-based farming practices have become ineffective due to increased population pressures and extreme climate variations. Recently, nanobiotechnology is considered to be a promising approach for sustainable crop production by improving the targeted nutrient delivery, pest management efficacy, genome editing efficiency, and smart plant sensor implications. This review provides deeper mechanistic insights into the potential applications of engineered nanomaterials for improved crop stress resilience and productivity. We also have discussed the technology readiness level of nano-based strategies to provide a clear picture of our current perspectives of the field. Current challenges and implications in the way of upscaling nanobiotechnology in the crop production are discussed along with the regulatory requirements to mitigate associated risks and facilitate public acceptability in order to develop research objectives that facilitate a sustainable nano-enabled Agri-tech revolution. Conclusively, this review not only highlights the importance of nano-enabled approaches in improving crop health, but also demonstrated their roles to counter global food security concerns.

Recent trends and perspectives in the application of metal and metal oxide nanomaterials for sustainable agriculture

Sustainable ecosystem management leads to the use of eco-friendly agricultural techniques for crop production. One of them is the use of metal and metal oxide nanomaterials and nanoparticles, which have proven to be a valuable option for the improvement of agricultural food systems. Moreover, the biological synthesis of these nanoparticles, from plants, bacteria, and fungi, also contributes to their eco-friendly and sustainable characteristics. Nanoparticles, which vary in size from 1 to 100 nm have a variety of mechanisms that are safer and more efficient than conventional fertilizers. Their usage as fertilizers and insecticides in agriculture is gaining favor in the scientific community to maximize crop output. More studies in this field will increase our understanding of this new technology and its broad acceptance in terms of performance, affordability, and environmental protection, as certain nanoparticles may outperform conventional fertilizers and insecticides. Accordingly, to the information gathered in this review, nanoparticles show remarkable potential for enhancing crop production, improving soil quality, and protecting the environment, however, metal and metal oxide NPs are not widely employed in agriculture. Many features of nanoparticles are yet left over, and it is necessary to uncover them. In this sense, this review article provides an overview of various types of metal and metal oxide nanoparticles used in agriculture, their characterization and synthesis, the recent research on them, and their possible application for the improvement of crop productivity in a sustainable manner.

Use of titanium dioxide doped multi-wall carbon nanotubes as promoter for the growth, biochemical indices of Sesamum indicum L. under heat stress conditions

The behavior of multi-walled carbon nanotubes (MWCNTs) and titanium dioxide nanoparticles (TiO2 NPs) as plant growth enhancers was still unclear; however, in this study, the effects of MWCNTs, TiO2NPs, 5%TiO2@MWCNTs, 10%TiO2@MWCNTs and 15%TiO2@MWCNTs on physical and biochemical contents in Sesamum indicum L. under heat stress conditions were studied. The content of malondialdehyde (MDA) and hydrogen peroxide (H2O2) concentrations were reduced by the spraying MWCNTs and TiO2 NPs on plants. The hydrogen peroxide (H2O2) content was reduced by 49.02% in plants treated with 15%TiO2@MWCNTs while 42.14% reduction was found in plants treated with 10%TiO2@MWCNTs. The proportion of oil and the peroxidase enzyme activity in plants treated with 15%TiO2@MWCNTs were increased by 48.99%, for the oil content, and 2.39 times for POD activity respected to the stressed plants. The proportion of unsaturated fatty acids increased in plants treated with 15%TiO2@MWCNTs, 10%TiO2@MWCNTs and TiO2 NPs by 2.7, 2.52, and 2.09 times, respectively, greater than the control of the Shandweel-3 variety. Finally, plants treated with 15%TiO2@MWCNTs showed increases in seed yield and weight 1000-seeds by 4.42 and 1.67 times, respectively. These findings suggest that TiO2@MWCNTs more effective than separated MWCNTs and TiO2 NPs in improve plant growth. In addition, the cultivar Shandweel-3 showed an improvement in growth indicators more than the Giza-32 cultivar.

The application of zinc oxide nanoparticles: An effective strategy to protect rice from rice blast and abiotic stresses

The causal agent of blast disease, the filamentous fungus Magnaporthe oryzae, leads to tremendous damage on rice production worldwide. Zinc oxide nanoparticles (ZnO NPs) have multi-functions in plant growth and antimicrobial activity. However, the effects of ZnO NPs on M. oryzae and disease resistance in rice are still unclear. Here, we showed that ZnO NPs have direct antifungal activity against M. oryzae by inhibiting its conidiation and appressorium formation. In addition, ZnO NPs significantly inhibit blast development and enhance basal resistance in rice by inducing ROS accumulation and expression of defense-related genes OsNAC4, OsPR10, OsKSL4, and OsPR1b. Furthermore, we showed that ZnO NPs treatment reduces ABA level in plant, leading to increased ROS accumulation and enhanced resistance against M. oryzae. Importantly, ZnO NPs treatment improves the tolerance of rice seedlings to osmotic and heat stresses.In conclusion, not only being an effective aid in fighting against blast disease, ZnO NPs also provides a novel strategy to enhance the tolerance of rice seedlings to abiotic stress.

Nanotechnology future in food using carbohydrate macromolecules: A state-of-the-art review

It is commonly known that agricultural pest and disease management is achieved through the use of agricultural chemicals and other synthetic compounds, which can contaminate water, soil, and food. Using agrochemicals indiscriminately has negative effects on the environment and poor food quality. In contrast, the world's population is increasing rapidly, and arable land is diminishing daily. Traditional agricultural methods must be replaced by nanotechnology-based treatments that efficiently address both the demands of the present and the needs of the future. As a promising contributor to sustainable agriculture and food production worldwide, nanotechnology has been applied through innovative and resourceful tools. Recent advances in nanomaterial engineering have increased agricultural and food sector production and protected crops using nanoparticles (1000 nm). Agrochemicals, nutrients, and genes can now be distributed to plants in a precise and tailored manner through nanoencapsulation (nanofertilizers, nanopesticides, and genes). Despite the advancement of technology in agriculture, some areas remain unexplored. The various agricultural domains must therefore be updated in priority order. The development of long-lasting and efficient nanoparticle materials will be key to the development of future eco-friendly and nanoparticle-based technologies. We thoroughly covered the many types of nanoscale agro-materials and gave an overview of biological techniques in nano-enabled tactics that can effectively reduce plant biotic and abiotic challenges while potentially boosting plant nutritional values.

Integrating nanotechnology with plant microbiome for next-generation crop health

Nanotechnology has enormous potential for sustainable agriculture, such as improving nutrient use efficiency, plant health, and food production. Nanoscale modulation of the plant-associated microbiota offers an additional valuable opportunity to increase global crop production and ensure future food and nutrient security. Nanomaterials (NMs) applied to agricultural crops can impact plant and soil microbiota, which offers valuable services to host plants, including the acquisition of nutrients, abiotic stress tolerance, and disease suppression. Dissecting the complex interactions between NMs and plants by integrating multi-omic approaches is providing new insights into how NMs can activate host responses and functionality as well as influence native microbial communities. Such nexus and moving beyond descriptive microbiome studies to hypothesis-driven research will foster microbiome engineering and open up opportunities for the development of synthetic microbial communities to provide agronomic solutions. Herein, we first summarize the significant role of NMs and the plant microbiome in crop productivity and then focus on NMs effects on plant-associated microbiota. We outline three urgent priority research areas and call for a transdisciplinary collaborative approach, involving plant scientists, soil scientists, environmental scientists, ecologists, microbiologists, taxonomists, chemists, physicists, and stakeholders, to advance nano-microbiome research. Detailed understanding of the nanomaterial-plant-microbiome interactions and the mechanisms underlying NMs-mediated shifts in the microbiome assembly and functions may help to exploit the services of both nano-objects and microbiota for next-generation crop health.

Bionanotechnology in Agriculture: A One Health Approach

Healthy eating habits are one of the requirements for the health of society. In particular, in natura foods are increasingly encouraged, since they have a high concentration of nutrients. However, these foods are often grown in the presence of agrochemicals, such as fertilizers and pesticides. To increase crop productivity and achieve high vigor standards in less time, farmers make excessive use of agrochemicals that generate various economic, environmental, and clinical problems. In this way, bionanotechnology appears as an ally in developing technologies to improve planting conditions, ranging from the health of farmers and consumers to the production of new foods and functional foods. All these improvements are based on the better use of land use in synergy with the lowest generation of environmental impacts and the health of living beings, with a view to the study and production of technologies that take into account the concept of One Health in its processes and products. In this review article, we will address how caring for agriculture can directly influence the quality of the most desired foods in contemporary society, and how new alternatives based on nanotechnology can point to efficient and safe solutions for living beings on our planet.

Green Fabrication, Characterization of Zinc Oxide Nanoparticles Using Plant Extract of Momordica charantia and Curcuma zedoaria and Their Antibacterial and Antioxidant Activities

In recent years, the rapid increase in the resistance of microorganisms to antibiotics has produced major health issues. Novel applications for these compounds have been developed by integrating modern technologies such as nanotechnology and material science with the innate antibacterial activity of metals. The current study demonstrated the synthesis of zinc oxide nanoparticles (ZnO NPs) from Momordica charantia and Curcuma zedoaria plant extracts, as well as their antibacterial properties. The synthesis of ZnO NPs was confirmed via UV-visible spectroscopy, showing clear peaks at 375 and 350 nm for M. charantia and C. zedoaria, respectively. Scanning electron microscopy (SEM) analysis revealed crystals of irregular shapes for the majority of the nanoparticles synthesized from both plants. The existence of ZnO NPs was confirmed using X-ray diffraction while the particle size was calculated using Scherrer's equation, which was 19.65 for C. zedoaria and 17.02 for M. charantia. Different functional groups were detected through Fourier transform infrared spectroscopy analysis. The antibacterial activity of the ZnO NPs at three different concentrations (250, 500, and 1000 µg/ml) was assessed against three different bacterial strains, i.e., Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), and Pseudomonas aeruginosa (P. aeruginosa), using disc diffusion methods. The ZnO nanoparticles showed promising antibacterial activity against bacterial strains. For C. zedoaria, the highest growth inhibition was observed at a concentration of 1000 µg/ml, which was 18, 19, and 18 mm as compared to antibiotics (15, 11, and 15.6 mm) against E. coli, P. aeruginosa, and S. aureus, respectively. Similarly, at 1000 µg/ml of NPs, M. charantia showed the highest growth inhibition (18, 15, and 17 mm) as compared to antibiotics (15, 11, and 14.6 mm) against E. coli, P. aeruginosa, and S. aureus, respectively. In conclusion, compared to pure plant extract and antibiotics, ZnO NPs at a higher concentration (1000 µg/ml) exhibited a significant difference in zone of inhibition against all the bacterial strains. Different concentrations of ZnO using M. charantia and C. zedoaria caused increments in the scavenging of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals and 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). The nanoparticles extracted using C. zedoaria exhibited higher antioxidant activity than M. charantia. Greenly synthesized ZnO nanoparticles have remarkable antibacterial properties and antioxidant activity, making them a promising contender for future pharmaceutical application.

Nanoencapsulation application to prolong postharvest shelf life

This review offers our opinion on current and future trends regarding nanoencapsulation interventions to extend postharvest shelf life of stored grains, fruits, and vegetables. Herein, we considered two major factors influencing postharvest shelf life for comments: aerobic food spoilage microorganisms and stored pests. Nanoemulsions, edible/active coatings, and nanopackaging loading essential oils as antimicrobial, antioxidant, or pesticide showed promising results in prolonged shelf life at room/cold storage without compromising quality, organoleptic properties, and postharvest physiology. Trends with nanoencapsulation using plant-based pesticides as agrochemical-free methods to keep produce fresh longer were commented as potential candidates for prolonging the shelf life of stored grains and fruits at the postharvest stage. Research with potential large-scale feasibility is intensive, but safety assessment is required and remains little explored.

Molecular and Physiological Mechanisms to Mitigate Abiotic Stress Conditions in Plants

Agriculture production faces many abiotic stresses, mainly drought, salinity, low and high temperature. These abiotic stresses inhibit plants' genetic potential, which is the cause of huge reduction in crop productivity, decrease potent yields for important crop plants by more than 50% and imbalance agriculture's sustainability. They lead to changes in the physio-morphological, molecular, and biochemical nature of the plants and change plants' regular metabolism, which makes them a leading cause of losses in crop productivity. These changes in plant systems also help to mitigate abiotic stress conditions. To initiate the signal during stress conditions, sensor molecules of the plant perceive the stress signal from the outside and commence a signaling cascade to send a message and stimulate nuclear transcription factors to provoke specific gene expression. To mitigate the abiotic stress, plants contain several methods of avoidance, adaption, and acclimation. In addition to these, to manage stress conditions, plants possess several tolerance mechanisms which involve ion transporters, osmoprotectants, proteins, and other factors associated with transcriptional control, and signaling cascades are stimulated to offset abiotic stress-associated biochemical and molecular changes. Plant growth and survival depends on the ability to respond to the stress stimulus, produce the signal, and start suitable biochemical and physiological changes. Various important factors, such as the biochemical, physiological, and molecular mechanisms of plants, including the use of microbiomes and nanotechnology to combat abiotic stresses, are highlighted in this article.

Novel Approaches for Sustainable Horticultural Crop Production: Advances and Prospects

Reduction of plant growth, yield and quality due to diverse environmental constrains along with climate change significantly limit the sustainable production of horticultural crops. In this review, we highlight the prospective impacts that are positive challenges for the application of beneficial microbial endophytes, nanomaterials (NMs), exogenous phytohormones strigolactones (SLs) and new breeding techniques (CRISPR), as well as controlled environment horticulture (CEH) using artificial light in sustainable production of horticultural crops. The benefits of such applications are often evaluated by measuring their impact on the metabolic, morphological and biochemical parameters of a variety of cultures, which typically results in higher yields with efficient use of resources when applied in greenhouse or field conditions. Endophytic microbes that promote plant growth play a key role in the adapting of plants to habitat, thereby improving their yield and prolonging their protection from biotic and abiotic stresses. Focusing on quality control, we considered the effects of the applications of microbial endophytes, a novel class of phytohormones SLs, as well as NMs and CEH using artificial light on horticultural commodities. In addition, the genomic editing of plants using CRISPR, including its role in modulating gene expression/transcription factors in improving crop production and tolerance, was also reviewed.

Silicon nanoparticles in higher plants: Uptake, action, stress tolerance, and crosstalk with phytohormones, antioxidants, and other signalling molecules

Silicon is absorbed as uncharged mono-silicic acid by plant roots through passive absorption of Lsi1, an influx transporter belonging to the aquaporin protein family. Lsi2 then actively effluxes silicon from root cells towards the xylem from where it is exported by Lsi6 for silicon distribution and accumulation to other parts. Recently, it was proposed that silicon nanoparticles (SiNPs) might share a similar route for their uptake and transport. SiNPs then initiate a cascade of morphophysiological adjustments that improve the plant physiology through regulating the expression of many photosynthetic genes and proteins along with photosystem I (PSI) and PSII assemblies. Subsequent improvement in photosynthetic performance and stomatal behaviour correspond to higher growth, development, and productivity. On many occasions, SiNPs have demonstrated a protective role during stressful environments by improving plant-water status, source-sink potential, reactive oxygen species (ROS) metabolism, and enzymatic profile. The present review comprehensively discusses the crop improvement potential of SiNPs stretching their role during optimal and abiotic stress conditions including salinity, drought, temperature, heavy metals, and ultraviolet (UV) radiation. Moreover, in the later section of this review, we offered the understanding that most of these upgrades can be explained by SiNPs intricate correspondence with phytohormones, antioxidants, and signalling molecules. SiNPs can modulate the endogenous phytohormones level such as abscisic acid (ABA), auxins (IAAs), cytokinins (CKs), ethylene (ET), gibberellins (GAs), and jasmonic acid (JA). Altered phytohormones level affects plant growth, development, and productivity at various organ and tissue levels. Similarly, SiNPs regulate the activities of catalase (CAT), ascorbate peroxidase (APX), superoxide dismutase (SOD), and ascorbate-glutathione (AsA-GSH) cycle leading to an upgraded defence system. At the cellular and subcellular levels, SiNPs crosstalk with various signalling molecules such as Ca²⁺, K⁺, Na⁺, nitric oxide (NO), ROS, soluble sugars, and transcription factors (TFs) was also explained.

Silicon nanoforms in crop improvement and stress management

Although, silicon - the second most abundant element in the earth crust could not supersede carbon (C) in the competition of being the building block of life during evolution, yet its presence has been reported in some life forms. In case of the plants, silicon has been reported widely to promote the plant growth under normal as well as stressful situations. Nanoform of silicon is now being explored for its potential to improve plant productivity and its tolerance against various stresses. Silicon nanoparticles (SiNPs) in the form of nanofertilizers, nanoherbicides, nanopesticides, nanosensors and targeted delivery systems, find great utilization in the field of agriculture. However, the mechanisms underlying their uptake by plants need to be deciphered in detail. Silicon nanoformss are reported to enhance plant growth, majorly by improving photosynthesis rate, elevating nutrient uptake and mitigating reactive oxygen species (ROS)-induced oxidative stress. Various studies have reported their ability to provide tolerance against a range of stresses by upregulating plant defense responses. Moreover, they are proclaimed not to have any detrimental impacts on environment yet. This review includes the up-to-date information in context of the eminent role of silicon nanoforms in crop improvement and stress management, supplemented with suggestions for future research in this field.

Preservation of Litchi Fruit with Nanosilver Composite Particles (Ag-NP) and Resistance against Peronophythora litchi

Litchi (Litchi chinensis Sonn.) is susceptible to infection by Peronophythora litchi post storage, which rapidly decreases the sensory and nutritional quality of the fruit. In this study, the effects of nanosilver (Ag-NP) solution treatment on the shelf life of litchi fruit and the inhibition of P. litchi were examined, and the underlying mechanisms were discussed. For investigations, we used one variety of litchi (‘Feizixiao’), dipping it in different concentrations of Ag-NP solution after harvesting. Meanwhile, we treated P. litchi with different concentrations of Ag-NP solution. According to the data analysis, litchi treated with 400 μg/mL Ag-NPs and stored at 4 °C had the highest health rate and the lowest browning index among all the samples. In the same trend, treatment with 400 μg/mL Ag-NPs produced the best results for anthocyanin content, total soluble solids content, and titratable acidity content. Additionally, according to the results of the inhibition test, 800 μg/mL Ag-NP solution had a 94.97% inhibition rate against P. litchi. Within 2–10 h following exposure to 400 μg/mL Ag-NP solution, the contents of superoxide dismutase, peroxidase, and catalase in P. litchi gradually increased and peaked, followed by a gradual decline. At this time, the integrity of the cell membrane of P. litchi could be broken by Ag-NP solution, and the sporangia showed deformed germ tubes and abnormal shapes. Taken together, these results suggested that Ag-NP treatment inhibited respiration and P. litchi activity, which might attenuate litchi pericarp browning and prolong the shelf life of litchi. Accordingly, Ag-NPs could be used as an effective antistaling agent in litchi fruit and as an ecofriendly fungicide for the post-harvest control of litchi downy blight. This study provides new insights into the application of Ag-NP as an antistaling agent for fruit storage and as an ecofriendly fungicide.

Effect of Silver Nanoparticles on the In Vitro Regeneration, Biochemical, Genetic, and Phenotype Variation in Adventitious Shoots Produced from Leaf Explants in Chrysanthemum

Novel and unique properties of nanomaterials, which are not apparent in larger-size forms of the same material, encourage the undertaking of studies exploring the multifaced effects of nanomaterials on plants. The results of such studies are not only scientifically relevant but, additionally, can be implemented to plant production and/or breeding. This study aimed to verify the applicability of silver nanoparticles (AgNPs) as a mutagen in chrysanthemum breeding. Chrysanthemum × grandiflorum (Ramat.) Kitam. ‘Lilac Wonder’ and ‘Richmond’ leaf explants were cultured on the modified MS medium supplemented with 0.6 mg·L⁻¹ 6-benzylaminopurine (BAP) and 2 mg·L⁻¹ indole-3-acetic acid (IAA) and treated with AgNPs (spherical; 20 nm in diameter size; 0, 50, and 100 mg·L⁻¹). AgNPs strongly suppressed the capability of leaf explants to form adventitious shoots and the efficiency of shoot regeneration. The content of primary and secondary metabolites (chlorophyll a, chlorophyll b, total chlorophylls, carotenoids, anthocyanins, phenolic compounds) and the activity of enzymatic antioxidants (superoxide dismutase and guaiacol peroxide) in leaf explants varied depending on the AgNPs treatment and age of culture. Phenotype variations of ex vitro cultivated chrysanthemums, covering the color and pigment content in the inflorescence, were detected in one 50 mg·L⁻¹ AgNPs-derived and five 100 mg·L⁻¹ AgNPs-derived ‘Lilac Wonder’ plants and were manifested as the color change from pink to burgundy-gold. However, no changes in inflorescence color/shape were found among AgNPs-treated ‘Richmond’ chrysanthemums. On the other hand, the stem height, number of leaves, and chlorophyll content in leaves varied depending on the AgNPs treatment and the cultivar analyzed. A significant effect of AgNPs on the genetic variation occurrence was found. A nearly two-fold higher share of polymorphic products, in both cultivars studied, was generated by RAPD markers than by SCoTs. To conclude, protocols using leaf explant treatment with AgNPs can be used as a novel breeding technique in chrysanthemum. However, the individual cultivars may differ in biochemical response, the efficiency of in vitro regeneration, genetic variation, and frequency of induced mutations in flowering plants.

Effect of Silver Nitrate (AgNO3) and Nano-Silver (Ag-NPs) on Physiological Characteristics of Grapes and Quality during Storage Period

The aim of this study was to evaluate the effects of silver nitrate (AgNO3) and nano-silver (Ag-NPs) on the physiological and biochemical characteristics, and quality of grape bunches during a cold storage period. For investigations, two varieties of grapes were used, Shine Muscat and Kyoho, with different concentrations of AgNO3 and Ag-NPs on post-harvest dipping. The data indicated that AgNO3 and Ag-NPs enhanced the fruits’ longevity and quality. Depending on the data analysis, it was found that the lowest weight loss value was obtained from Ag-NP treated grapes, followed by AgNO3 treated grapes, while the highest loss occurred in the control grapes. Immersion of grape bunches in Ag-NPs was the best application for maintenance of overall storage quality for both cultivars. In the same trend, treatment with Ag-NPs produced the best results for soluble solids content (SSC), titratable acidity (TA), malondialdehyde (MDA) content, polyphenol oxidase (PPO), pyrogallol peroxidase (POD), and pectin methylestraese activity (PME). It was concluded that Ag-NPs and AgNO3 were helpful in maintaining the quality of grape bunches up to 30 days, while grape bunches under control conditions were spoiled with 30 days of cold storage.

CRISPR/Cas9 and Nanotechnology Pertinence in Agricultural Crop Refinement

The CRISPR/Cas9 (Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR-associated protein 9) method is a versatile technique that can be applied in crop refinement. Currently, the main reasons for declining agricultural yield are global warming, low rainfall, biotic and abiotic stresses, in addition to soil fertility issues caused by the use of harmful chemicals as fertilizers/additives. The declining yields can lead to inadequate supply of nutritional food as per global demand. Grains and horticultural crops including fruits, vegetables, and ornamental plants are crucial in sustaining human life. Genomic editing using CRISPR/Cas9 and nanotechnology has numerous advantages in crop development. Improving crop production using transgenic-free CRISPR/Cas9 technology and produced fertilizers, pesticides, and boosters for plants by adopting nanotechnology-based protocols can essentially overcome the universal food scarcity. This review briefly gives an overview on the potential applications of CRISPR/Cas9 and nanotechnology-based methods in developing the cultivation of major agricultural crops. In addition, the limitations and major challenges of genome editing in grains, vegetables, and fruits have been discussed in detail by emphasizing its applications in crop refinement strategy.

The potential of foliar application of nano-chitosan-encapsulated nano-silicon donor in amelioration the adverse effect of salinity in the wheat plant

BACKGROUND

Nano-materials ameliorate the adverse effect of salinity stress on the physiological and biochemical processes in plants. The present investigation was designed to evaluate the physiological mechanisms through which a nano-chitosan-encapsulated nano-silicon fertilizer (NC-NS) can ameliorate the adverse effect of salinity stress on the wheat plants, and compare it with nano-chitosan (NC) and nano-silicon (NS) application. Nano-silicon was encapsulated with a chitosan-tripolyphosphate (TPP) nano-matrix by ionic gelation method for its slow release. The wheat plants were exposed to foliar application of distilled water, NC, NS, and NC-NS with two NaCl irrigation levels at 0 (distilled water) and 100 mM.

RESULTS

The foliar application of NC, NS, and NC-NS induced a significant increase in the function of enzymatic and non-enzymatic antioxidant systems of the wheat plants to equilibrate cellular redox homeostasis by balancing H2O2 content in the leaves and roots, as compared with salt-stressed plants without treatment. The plant's foliar-sprayed with NC, NS, and NC-NS solution exhibited a significant increase in the molecules with osmotic adjustment potentials such as proline, free amino acids, glycine betaine, and sugars to protect cells against osmotic stress-induced by salinity. The observed increase in the antioxidant power and osmoregulatory at NC, NS, and NC-NS application was accompanied by the protection of lipid membrane, proteins and photosynthetic apparatus against salinity stress.

CONCLUSION

In the present study, the beneficial role of NC, NS, and NC-NS application, particularly NC-NS, in alleviating the adverse effect of salinity stress on antioxidant systems and osmotic adjustment in wheat is well documented. An overview of the result of present study assists researchers in providing a potential solution for this increasing salinization threat in crops.

Effects of Metal Nanoparticles and Other Preparative Materials in the Environment on Plants: From the Perspective of Improving Secondary Metabolites

The influence of preparation material residues in wastewater and soil on plants has been paid more and more attention by researchers. Secondary metabolites play an important role in the application of plants. It was found that nanomaterials can increase the content of plant secondary metabolites in addition to their role in pharmaceutical preparations. For example, 800 mg/kg copper oxide nanoparticles (NPs) increased the content of p-coumaric acid in cucumber by 225 times. Nanoparticles can cause oxidative stress in plants, increase signal molecule, and upregulate the synthase gene expression, increasing the content of secondary metabolites. The increase of components such as polyphenols and total flavonoids may be related to oxidative stress. This paper reviews the application and mechanism of metal nanomaterials (Ag-NP, ZnO-NP, CeO₂-NP, Cds-NP, Mn-NP, CuO-NP) in promoting the synthesis of secondary metabolites from plants. In addition, the effects of some other preparative materials (cyclodextrins and immobilized molds) on plant secondary metabolites are also involved. Finally, possible future research is discussed.

Recent Advancements and Development in Nano-Enabled Agriculture for Improving Abiotic Stress Tolerance in Plants

Abiotic stresses, such as heavy metals (HMs), drought, salinity and water logging, are the foremost limiting factors that adversely affect the plant growth and crop productivity worldwide. The plants respond to such stresses by activating a series of intricate mechanisms that subsequently alter the morpho-physiological and biochemical processes. Over the past few decades, abiotic stresses in plants have been managed through marker-assisted breeding, conventional breeding, and genetic engineering approaches. With technological advancement, efficient strategies are required to cope with the harmful effects of abiotic environmental constraints to develop sustainable agriculture systems of crop production. Recently, nanotechnology has emerged as an attractive area of study with potential applications in the agricultural science, including mitigating the impacts of climate change, increasing nutrient utilization efficiency and abiotic stress management. Nanoparticles (NPs), as nanofertilizers, have gained significant attention due to their high surface area to volume ratio, eco-friendly nature, low cost, unique physicochemical properties, and improved plant productivity. Several studies have revealed the potential role of NPs in abiotic stress management. This review aims to emphasize the role of NPs in managing abiotic stresses and growth promotion to develop a cost-effective and environment friendly strategy for the future agricultural sustainability.

Zinc Oxide Nanoparticles Interplay With Physiological and Biochemical Attributes in Terminal Heat Stress Alleviation in Mungbean (Vigna radiata L.)

Gradually rising atmospheric temperature is the vital component of the environment, which is anticipated as the riskiest abiotic stress for crop growth. Nanotechnology revolutionizing the agricultural sectors, notably, zinc oxide nanoparticles (nano-ZnO) has captured intensive research interests due to their distinctive properties and numerous applications against abiotic stresses. Mungbean (Vigna radiata L.), being a summer crop, is grown all over the world at an optimum temperature of 28-30°C. A rise in temperature above this range, particularly during the flowering stage, can jeopardize the potential performance of the plant. Hence, an outdoor study was performed to evaluate the effect of multiple suspensions of nano-ZnO (0, 15, 30, 45, and 60 mg l^-1) on physicochemical attributes and yield of mungbean crop under heat stress. Heat stress was induced by fine-tuning of sowing time as: S1 is the optimal sowing time having day/night temperatures <40/25°C and S2 and S3 are late sown that were above >40/25°C during the flowering stage. In vitro studies on Zn release from nano-ZnO by inductively coupled plasma mass spectroscopy (ICPMS) disclosed that the Zn release and particles uptake from nano-ZnO were concentration-dependent. Exogenous foliar application of nano-ZnO significantly upstreamed the production of antioxidants and osmolytes to attenuate the shocks of heat stress in S2 and S3. Likewise, nano-ZnO substantially rebated the production of reactive oxygen species in both S2 and S3 that was associated with curtailment in lipid peroxidation. Adding to that, foliar-applied nano-ZnO inflates not only the chlorophyll contents and gas exchange attributes, but also the seeds per pod (SPP) and pods per plant (PPP), which results in the better grain yield under heat stress. Thus, among all the sowing dates, S1 statistically performed better than S2 and S3, although foliar exposure of nano-ZnO boosted up mungbean performance under both the no heat and heat-induced environments. Hence, foliar application of nano-ZnO can be suggested as an efficient way to protect the crop from heat stress-mediated damages with the most negligible chances of nanoparticles delivery to environmental compartments that could be possible in case of soil application.

Chemical Properties, Nutritional Quality, and Bioactive Components of Horticulture Food

The Special Issue “Chemical Properties, Nutritional Quality, and Bioactive Components of Horticulture Food” is here presented [...]