Sustainable Production of Tomato Plants (Solanum lycopersicum L.) under Low-Quality Irrigation Water as Affected by Bio-Nanofertilizers of Selenium and Copper

Differential impact of plant-based selenium nanoparticles on physio-biochemical properties, antioxidant defense system and protein regulation in fruits of huanglongbing-infected 'Kinnow' mandarin plants

Huanglongbing disease (HLB) is the most severe citrus disease destroying Citrus reticulata L. 'Kinnow', the most commonly grown mandarin in Pakistan. It is caused by Candidatus Liberibacter bacterial species and it spreads through the sucking Asian citrus psyllid insect. The current study was designed to investigate the potential impact of plant extract mediated selenium nanoparticles (SeNPs) on antioxidant defense system, fruit quality and protein regulation in the fruits of HLB-infected 'Kinnow' mandarin plants. Garlic cloves extract was used as reducing and capping agent for the synthesis of SeNPs. Various concentrations of SeNPs (25, 50, 75, and 100 mg L-1) were exogeneously applied to HLB-positive citrus plants. SeNPs at the concentration of 75 mg L-1 affected positively fruit physio-biochemical parameters, e.g., peel thickness, peel weight, fruit weight, fruit diameter, total soluble solids, juice volume, ascorbic acid content and reduced total acidity. Furthermore, SeNPs also enhanced the amounts of total protein and total sugar as well as elevated antioxidant enzymes, e.g., superoxide dismutase, peroxidases, and catalases. Non-enzymatic antioxidant content, e.g., total phenolic and total flavonoids, was also elevated. Proteomics analysis revealed that exposure to SeNPs at the concentration of 75 mg·L-1 significantly altered in HLB infected mandarin fruting plants the expression of proteins associated with transcription, protection, cell wall biogenesis, cell wall organization, reproduction, stamen formation, embryo development, inflorescence development, as well as translation and response to oxidative stress. Our results revealed that foliar application of SeNPs influences the protein contents positively, therefore ameliorating fruit physio-biochemical quality by boosting antioxidant defense systems of HLB-infected 'Kinnow' mandarin plants.

Recent advances in nano-fertilizers: synthesis, crop yield impact, and economic analysis

The escalating global demand for food production has predominantly relied on the extensive application of conventional fertilizers (CFs). However, the increased use of CFs has raised concerns regarding environmental risks, including soil and water contamination, especially within cereal-based cropping systems. In response, the agricultural sector has witnessed the emergence of healthier alternatives by utilizing nanotechnology and nano-fertilizers (NFs). These innovative NFs harness the remarkable properties of nanoparticles, ranging in size from 1 to 100 nm, such as nanoclays and zeolites, to enhance nutrient utilization efficiency. Unlike their conventional counterparts, NFs offer many advantages, including variable solubility, consistent and effective performance, controlled release mechanisms, enhanced targeted activity, reduced eco-toxicity, and straightforward and safe delivery and disposal methods. By facilitating rapid and complete plant absorption, NFs effectively conserve nutrients that would otherwise go to waste, mitigating potential environmental harm. Moreover, their superior formulations enable more efficient promotion of sustainable crop growth and production than conventional fertilizers. This review comprehensively examines the global utilization of NFs, emphasizing their immense potential in maintaining environmentally friendly crop output while ensuring agricultural sustainability.

Impact of Argemone mexicana L. on tomato plants infected with Phytophthora infestans

Background

Fungal diseases can cause significant losses in the tomato crop. Phytophthora infestans causes the late blight disease, which considerably affects tomato production worldwide. Weed-based plant extracts are a promising ecological alternative for disease control.

Methods

In this study, we analyzed the plant extract of Argemone mexicana L. using chromatography-mass spectrometry analysis (GC-MS). We evaluated its impact on the severity of P. infestans, as well as its effect on the components of the antioxidant defense system in tomato plants.

Results

The extract from A. mexicana contains twelve compounds most have antifungal and biostimulant properties. The findings of the study indicate that applying the A. mexicana extract can reduce the severity of P. infestans, increase tomato fruit yield, enhance the levels of photosynthetic pigments, ascorbic acid, phenols, and flavonoids, as well as decrease the biosynthesis of H2O2, malondialdehyde (MDA), and superoxide anion in the leaves of plants infected with this pathogen. These results suggest that using the extract from A. mexicana could be a viable solution to control the disease caused by P. infestans in tomato crop.

Unlocking the Potential of Nano-Enabled Precision Agriculture for Efficient and Sustainable Farming

Nanotechnology has attracted remarkable attention due to its unique features and potential uses in multiple domains. Nanotechnology is a novel strategy to boost production from agriculture along with superior efficiency, ecological security, biological safety, and monetary security. Modern farming processes increasingly rely on environmentally sustainable techniques, providing substitutes for conventional fertilizers and pesticides. The drawbacks inherent in traditional agriculture can be addressed with the implementation of nanotechnology. Nanotechnology can uplift the global economy, so it becomes essential to explore the application of nanoparticles in agriculture. In-depth descriptions of the microbial synthesis of nanoparticles, the site and mode of action of nanoparticles in living cells and plants, the synthesis of nano-fertilizers and their effects on nutrient enhancement, the alleviation of abiotic stresses and plant diseases, and the interplay of nanoparticles with the metabolic processes of both plants and microbes are featured in this review. The antimicrobial activity, ROS-induced toxicity to cells, genetic damage, and growth promotion of plants are among the most often described mechanisms of operation of nanoparticles. The size, shape, and dosage of nanoparticles determine their ability to respond. Nevertheless, the mode of action of nano-enabled agri-chemicals has not been fully elucidated. The information provided in our review paper serves as an essential viewpoint when assessing the constraints and potential applications of employing nanomaterials in place of traditional fertilizers.

Nanobiotechnology in crop stress management: an overview of novel applications

Agricultural crops are subject to a variety of biotic and abiotic stresses that adversely affect growth and reduce the yield of crop plantss. Traditional crop stress management approaches are not capable of fulfilling the food demand of the human population which is projected to reach 10 billion by 2050. Nanobiotechnology is the application of nanotechnology in biological fields and has emerged as a sustainable approach to enhancing agricultural productivity by alleviating various plant stresses. This article reviews innovations in nanobiotechnology and its role in promoting plant growth and enhancing plant resistance/tolerance against biotic and abiotic stresses and the underlying mechanisms. Nanoparticles, synthesized through various approaches (physical, chemical and biological), induce plant resistance against these stresses by strengthening the physical barriers, improving plant photosynthesis and activating plant defense mechanisms. The nanoparticles can also upregulate the expression of stress-related genes by increasing anti-stress compounds and activating the expression of defense-related genes. The unique physico-chemical characteristics of nanoparticles enhance biochemical activity and effectiveness to cause diverse impacts on plants. Molecular mechanisms of nanobiotechnology-induced tolerance to abiotic and biotic stresses have also been highlighted. Further research is needed on efficient synthesis methods, optimization of nanoparticle dosages, application techniques and integration with other technologies, and a better understanding of their fate in agricultural systems.

Enhanced edible plant production using nano-manganese and nano-iron fertilizers: Current status, detection methods and risk assessment

BACKGROUND

Nanotechnology offers many benefits in the globally important field of food production and human nutrition, particularly by implementing agricultural nanoproducts. Of these, edible plant fertilizers enriched with nanosized forms of essential metals, Mn and Fe, are growing in importance with the advantages of enhanced action on plant roots.

SCOPE AND APPROACH

This review focuses on the importance of tracking the bioaccumulation and biodistribution of these pertinent nanofertilizers. An emphasis is given to the critical analysis of the state-of-the-art analytical strategies to examine the Mn and Fe nanoparticles in edible plant systems as well as to shedding light on the vast gap in the methodologies dedicated to the speciation, in vitro simulation, and safety testing of these promising nanomaterials. Also provided are guidances for the food chemists and technologists on the lights and shadows of particular analytical approaches as a matter of authors' expertise as analytical chemists.

KEY FINDINGS AND CONCLUSIONS

While the use of nanotechnology in agriculture seems to be growing increasingly, there is still a lack of analytical methodologies capable of investigating novel Mn- and Fe-based nanomaterials as potential fertilizers. Only the advent of reliable analytical tools in the field could bridge the gaps in our knowledge about processes in which those materials participate in the plant systems and their effects on crop production and quality of the produced food.

Synergistic impact of nanomaterials and plant probiotics in agriculture: A tale of two-way strategy for long-term sustainability

Modern agriculture is primarily focused on the massive production of cereals and other food-based crops in a sustainable manner in order to fulfill the food demands of an ever-increasing global population. However, intensive agricultural practices, rampant use of agrochemicals, and other environmental factors result in soil fertility degradation, environmental pollution, disruption of soil biodiversity, pest resistance, and a decline in crop yields. Thus, experts are shifting their focus to other eco-friendly and safer methods of fertilization in order to ensure agricultural sustainability. Indeed, the importance of plant growth-promoting microorganisms, also determined as "plant probiotics (PPs)," has gained widespread recognition, and their usage as biofertilizers is being actively promoted as a means of mitigating the harmful effects of agrochemicals. As bio-elicitors, PPs promote plant growth and colonize soil or plant tissues when administered in soil, seeds, or plant surface and are used as an alternative means to avoid heavy use of agrochemicals. In the past few years, the use of nanotechnology has also brought a revolution in agriculture due to the application of various nanomaterials (NMs) or nano-based fertilizers to increase crop productivity. Given the beneficial properties of PPs and NMs, these two can be used in tandem to maximize benefits. However, the use of combinations of NMs and PPs, or their synergistic use, is in its infancy but has exhibited better crop-modulating effects in terms of improvement in crop productivity, mitigation of environmental stress (drought, salinity, etc.), restoration of soil fertility, and strengthening of the bioeconomy. In addition, a proper assessment of nanomaterials is necessary before their application, and a safer dose of NMs should be applicable without showing any toxic impact on the environment and soil microbial communities. The combo of NMs and PPs can also be encapsulated within a suitable carrier, and this method aids in the controlled and targeted delivery of entrapped components and also increases the shelf life of PPs. However, this review highlights the functional annotation of the combined impact of NMs and PPs on sustainable agricultural production in an eco-friendly manner.

Nanofungicides with Selenium and Silicon Can Boost the Growth and Yield of Common Bean (Phaseolus vulgaris L.) and Control Alternaria Leaf Spot Disease

There is an urgent need to reduce the intensive use of chemical fungicides due to their potential damage to human health and the environment. The current study investigated whether nano-selenium (nano-Se) and nano-silica (nano-SiO2) could be used against the leaf spot disease caused by Alternaria alternata in a common bean (Phaseolus vulgaris L.). The engineered Se and SiO2 nanoparticles were compared to a traditional fungicide and a negative control with no treatment, and experiments were repeated during two successive seasons in fields and in vitro. The in vitro study showed that 100 ppm nano-Se had an efficacy rate of 85.1% on A. alternata mycelial growth, followed by the combined applications (Se + SiO2 at half doses) with an efficacy rate of 77.8%. The field study showed that nano-Se and the combined application of nano-Se and nano-SiO2 significantly decreased the disease severity of A. alternata. There were no significant differences among nano-Se, the combined application, and the fungicide treatment (positive control). As compared to the negative control (no treatment), leaf weight increased by 38.3%, the number of leaves per plant by 25.7%, chlorophyll A by 24%, chlorophyll B by 17.5%, and total dry seed yield by 30%. In addition, nano-Se significantly increased the enzymatic capacity (i.e., CAT, POX, PPO) and antioxidant activity in the leaves. Our current study is the first to report that the selected nano-minerals are real alternatives to chemical fungicides for controlling A. alternata in common beans. This work suggests the potential of nanoparticles as alternatives to fungicides. Further studies are needed to better understand the mechanisms and how different nano-materials could be used against phytopathogens.

Biological Nanofertilizers to Enhance Growth Potential of Strawberry Seedlings by Boosting Photosynthetic Pigments, Plant Enzymatic Antioxidants, and Nutritional Status

Strawberry production presents special challenges due the plants' shallow roots. The rooting stage of strawberry is a crucial period in the production of this important crop. Several amendments have been applied to support the growth and production of strawberry, particularly fertilizers, to overcome rooting problems. Therefore, the current investigation was carried out to evaluate the application of biological nanofertilizers in promoting strawberry rooting. The treatments included applying two different nanofertilizers produced biologically, nano-selenium (i.e., 25, 50, 75, and 100 mg L^-1) and nano-copper (i.e., 50 and 100 mg L^-1), plus a control (untreated seedlings). The rooting of strawberry seedlings was investigated by measuring the vegetative growth parameters (root weight, seedling weight, seedling length, and number of leaves), plant enzymatic antioxidants (catalase, peroxidase, and polyphenol oxidase activity), and chlorophyll content and its fluorescence and by evaluating the nutritional status (content of nutrients in the fruit and their uptake). The results showed that the applied nanofertilizers improved the growth, photosynthetic pigments, antioxidant content, and nutritional status of the seedlings compared to the control. A high significant increase in nutrient contents reached to more than 14-fold, 6-fold, 5-folf, and 4-fold for Cu, Mn, N, and Se contents, respectively, due to the applied nanofertilizers compared with the control. The result was related to the biological roles of both Se and CuO in activating the many plant enzymes. Comparing the Se with the CuO nanofertilizer, Cu had the strongest effect, which was shown in the higher values in all studied properties. This study showed that nanofertilizers are useful to stimulate strawberry seedling growth and most likely would also be beneficial for other horticultural crops. In general, the applied 100 ppm of biological nano-Se or nano-CuO might achieve the best growth of strawberry seedlings under growth conditions in greenhouses compared to the control. Along with the economic dimension, the ecological dimension of biological nanofertilizers still needs more investigation.

Effects of brown seaweed extract, silicon, and selenium on fruit quality and yield of tomato under different substrates

Tomatoes (Lycopersicun esculentum L.) are an important group of vegetable crops that have high economical and nutritional value. The use of fertilizers and appropriate substrates is one of the important strategies that can assist in increasing the yield and quality of fruits. The present study aimed to investigate the effects of exogenous seaweed extract (Nizamuddinia zanardinii), silicon (Na2SiO3), and selenium (Na2SeO3) on quality attributes and fruit yield (FY) of tomato under palm peat + perlite and coco peat + perlite substrates. Seaweed extract significantly improved several of the fruit quality attributes such as total carbohydrate content, total soluble solids (TSS), and pH as well as the FY. The results showed that silicon (Si) (75 mg) was the best foliar spray treatment to enhance the fruit firmness (30.46 N), fruit volume (196.8 cm3), and FY (3320.5 g). The highest amount of plant yield (3429.33 g) was obtained by the interaction effects of silicon (75 mg L-1) under the effect of palm peat. The use of selenium (Se) led to improvements in flavor index (TSS/TA). Also, the application of palm peat + perlite substrate caused an increase in vitamin C (16.62 mg/100g FW), compared to other substrates (14.27 mg/100g FW). The present study suggested that foliar spray with seaweed extract and Si had beneficial effects on the quality and FY of tomatoes. Also, the palm peat substrate can be used as a good alternative to the coco peat substrate in the hydroponic system.

Can Nanofertilizers Mitigate Multiple Environmental Stresses for Higher Crop Productivity?

The global food production for the worldwide population mainly depends on the huge contributions of the agricultural sector. The cultivated crops of foods need various elements or nutrients to complete their growth, and these are indirectly consumed by humans. During this production, several environmental constraints or stresses may cause losses in the global agricultural production. These obstacles may include abiotic and biotic stresses, which have already been studied in both individual and combined cases. However, there are very few studies on multiple stresses. On the basis of the myriad benefits of nanotechnology in agriculture, nanofertilizers (or nanonutrients) have become promising tools for agricultural sustainability. Nanofertilizers are also the proper solution to overcoming the environmental and health problems that can result from conventional fertilizers. The role of nanofertilizers has increased, especially under different environmental stresses, which can include individual, combined, and multiple stresses. The stresses are most commonly the result of nature; however, studies are still needed on the different stress levels. Nanofertilizers can play a crucial role in supporting cultivated plants under stress and in improving the plant yield, both quantitatively and qualitatively. Similar to other biological issues, many open-ended questions still require further investigation: Is the right time and era for nanofertilizers in agriculture? Will the nanofertilizers be the dominant source of nutrients in modern agriculture? Are nanofertilizers, and particularly biological synthesized ones, the magic solution for sustainable agriculture? What are the expected damages of multiple stresses on plants?