Nano silver and emerging agricultural applications

Arable agriculture is the foundation of most developing economies, with about 60% of the population dependent on agriculture. The agricultural division of India represents 18% of India’s total national output and provides jobs for 50% of the country’s workforce. Research fields such as plant disease detection, soil quality improvement, nanostructuring and seed germination are still areas of interest and attraction for researchers. In response to this fascinating field, Nanotechnology, an area of ​​interdisciplinary research, is providing the foundation. For example, advances in nano fertilizers, which are having high absorption efficiency into target plants due to high surface-to-volume ratios. Using nano phosphorus fertilizer, absorption efficiency up to 90.6%. Another beneficial aspect of the application of nano fertilizers is the ability to deliver slow-release nutrients to plants over a period of 40-50 days, rather than over a 4-10 day period of fertilizers. Conventional fertilization. In this article, we briefly discussed the application of nanotechnology from an agricultural perspective. Here, we have summarized the applications of  nano silver (Ag) in agriculture such as crop yield, crop disease detection, food packaging, soil quality, and more.

1. INTRODUCE

The obvious basic human needs include food, shelter, clothing and medicine, … Agriculture is one of the main industries that provide food for people, indirectly or directly other bridge. Increasing population leads to a great increase in demand for all of these things even though natural resources are readily available from cultivation. Therefore, it is of the utmost importance to learn about knowledge in the agricultural sector and to use new technologies for efficient crop production.

Although the agricultural sector has also adopted technology-based farming known as “smart farming”, there is scope for research on this issue for improvement. Agricultural production faces the challenge of increasing crop production and providing adequate nutritious rations for a growing population, in extreme uncertain climatic conditions, water scarcity, and acreage. limited (and degraded in many places) soils, and mostly poor quality water and air, are associated with changes in natural biodiversity.

To address these problems, it is necessary to explore one of the cutting-edge technologies such as ‘Nanotechnology’ to develop intelligent ways to promote crop yields while ensuring environmental safety and efficiency. use higher. Nanotechnology processes particles at the nanoscale (1-100 nm). Materials that are microscopic when reduced to nanoscale exhibit differentiating properties due to quantum restriction. [first]

The size-dependent properties of nanomaterials lead to unique applications. Nanoscience has revolutionized potential fields by developing processes and products that are difficult to evolve through conventional methods. The supporting applications of nanotechnology have the potential to change agricultural production by enabling better management and conservation of the inputs of plant and animal production.

In the agricultural sector, it can be used for pest management through the formulation of insecticides and pesticides based on nanomaterials, improving agricultural productivity by using particles. Specialized bio-conjugate (encapsulated) nanoparticles for slow release of nutrients and water, nanoparticle intermediate genes and for preparing a wide variety of biosensors for precise farming.

The application of nanotechnology in the agriculture and food industries was first mentioned in a US Department of Agriculture roadmap published in September 2003. [2]

The use of nanotechnology in agriculture is mostly theoretical but it has already begun and will continue to have a significant effect in the main areas of agricultural development using new functional materials, product development and effective food safety and biosecurity measuring equipment. [3]

Researchers have shown increased crop yields using nanomaterials in many ways. Agricultural scientists have drawn in the direction of the nanomaterial revolution. Silver nanoparticles as antifungal and antimicrobial agents play a role in protecting agricultural crops, where they also regulate proper nutrition for the crop. [4]

Nanosensors use carbon nanotubes or nanotransformers small enough to trap and measure individual proteins or even small molecules. [5] Zinc oxide nanoparticles (average particle size 25 nm) promoted seed germination, seedling vitality, and plant growth and were shown to be effective in increasing seed germination. development of stems and roots in peanuts. A research team at the University of Leeds in the UK has determined that magnesium oxide and zinc oxide nanoparticles are highly effective at killing microorganisms and can be used in food packaging. [6]

Research was performed on the application of Fe, Ag, Mn, Zn, Cu, Mo, Ti and carbon nanotubes as nano fertilizers and nano pesticides to improve plant growth as well as plant protection. [7] Therefore, it can be proposed that appropriate innovations in the application of nanotechnology in the agricultural sector will be a challenging phenomenon in the future and have the potential to revolutionize agricultural production. and food and to help maintain the sustainability of agricultural products as appropriate.

Figure 1 shows different applications of nanotechnology in the agricultural sector. In that context, these articles have synthesized the applications of nano silver (Ag) in pest control, crop improvement, plant disease detection, and food packaging. In order to carry out AgNp applications, the preparation of these particles must be done in a more systematic manner. Silver nanoparticles can be synthesized by physical, chemical and biological methods.

Due to the requirements of harsh conditions and toxic chemicals in physical and chemical methods, the biological method is widely used. As one-step and environmentally friendly synthesis, various researchers have synthesized silver nanoparticles from various sources such as plant extracts, bacteria, fungi, etc.

2. Application of nano silver

Silver nanoparticles are the most researched and used nanoparticles for biological systems. It has been known to have strong inhibitory and bactericidal effects as well as a wide range of antimicrobial activities. Silver nanoparticles, with a high surface area and a high atomic surface ratio, have a high antimicrobial effect compared to cubic silver. Additionally, AgNPs have been well-recognized for their antioxidant, antibacterial, antifungal, antiviral, and anti-inflammatory properties. It is often mentioned that the use of nano silver in agriculture is primarily theoretical, but in the near future researchers will have diverse applications of silver nanoparticles.

2.1 Plant growth enhancement

AgNPs have been used as a potential candidate for increasing crop yield by enhancing seed germination and plant growth. Concentrations of silver nanoparticles (AgNPs) affect the growth response of plants with positive or negative effects. Effects of Ag concentration on growth parameters of wheat, cowpea and Brassica are shown in Figure 2.

The specific concentration of Ag nanoparticles must be optimized. The effect of nano silver with a diameter of 20 nm on fenugreek seeds (Trigonella foenum-graecum) was performed. [9] Different concentrations of silver nanoparticles (0, 10, 20, 30 and 40 μg mL-1) were used and the results showed maximum seed germination (76.11%), germination (4,102), root length (76.94 mm), fresh root weight (2,783) and dry weight of roots (1,204) at concentration 10 μg mL− 1.

Exposing plants to specific concentrations of AgNP may promote plant growth compared to non-exposed plants, while higher and lower concentrations may have a growth inhibitory effect. . [10] AgNPs growth responses using different concentrations (0, 25, 50, 100, 200 and 400 ppm) in chrysanthemum and it was systematically concluded that the 50 ppm treatment was determined to be optimal with a positive effect on fresh weight, roots and shot length. [11]

In addition, AgNPs concentration responsible for the effects observed in both cowpea and Brassica; In cowpea, a concentration of 50 ppm promotes growth and indirectly increases root nodules. [12] These results show that the application of silver nanoparticles can be used to significantly enhance the seed germination ability, average germination time, seed germination index, seed vigor, fresh weight and dry weight.

Figure 2 Effect of Ag concentration on growth parameters of wheat, cowpea and Brassica (reproduced with permission of [12], Copyright 2016, The Author). 2.2 Plant disease management and plant protection The control of plant diseases on food crops and fruit trees is an important economic sector and needs to be studied.

Colloidal AgNPs that are well dispersed and stabilized will more adhere to the surface of bacteria and fungi cells, thus acting as a better disinfectant and fungicide. [13] Figure 3 shows the application of nanomaterials as protective agents or carriers to protect plants. Researchers have made remarkable achievements in plant disease control with the application of AgNPs.

The DNA directing silver nanoparticles was developed on graphene oxide and studied antibacterial activity against xanthomonas perforans, a bacterial spot pathogen in Tomatoes. [14] The antibacterial activity of plant extracts is due to the presence of secondary metabolites such as tannins, saponins and glycosides. [15]

The in vitro antifungal activity of AgNPs against nineteen different plant pathogenic fungi was studied. [16] Arginine cationic gold nanoparticles (ArgNPs) assembled Cas9En (E-tag) -RNP (ribonucleoprotein) for sgRNA distribution provided about 30% efficiency of cytoplasmic / nuclear gene editing in cultured cell lines. Transplanting, this will facilitate future crop research and development. [17] The antifungal activity of silver nanoparticles synthesized by trichoderma longibrachiatum, against nine fungal isolates such as alternative aspergillus and others. [18]

Bacterial diseases are one of the causes of significant loss of crop yields worldwide. AgNPs have been shown to be active against pathogenic bacteria in plants. It was revealed that AgNPs have high antibacterial activity against erwinia cartovora, E. compared with conventional antibiotics. [19] They also studied the antifungal activity of AgNPs against pathogenic fungal viz. Fusarium oxysporum, Alternaria alterta and aspergillus flavus showed promising results. The antifungal effect of colloidal silver nanoparticles (mean diameter 1.5 nm) on the rose white pollen disease caused by sphaerotheca pannosa var rosae. This is a very widespread and common disease for both indoor roses and outdoor roses. It causes leaf distortion, leaf curling, premature defoliation and decreased flowering. The double silvered nano is prepared by the chemical reaction of silver ions with the help of a physical method, a reducing agent and a stabilizer. It helps to remove undesirable microorganisms in soil and hydroponic systems. Furthermore, silver is an excellent plant growth stimulant.

2.3 Use as a pesticide

Nano silver have been tested as pesticides to reduce the pest burden from plants. It has a need to protect pests and to enrich nutrients. This reduces the regular use of chemical fertilizers in conventional farming. It can destroy undesirable microorganisms in soil and hydroponic systems. As shown in Figure 4, it is being used as a foliar spray to prevent mold, mold, rot and a number of other microbial related plant diseases. [20] Aqueous silver solution, used to treat plants, is reported to have an excellent preventive effect on pathogenic microorganisms that cause powdery mildew or mildew in plants. Furthermore, it promotes the physiological activity and growth of plants, causes disease and is stress resistant in plants.

2.4 Food packaging

Post-harvest management, including agricultural preservation, is one of the most important sectors of agriculture. Previous studies have reported that antimicrobial packaging based on AgNPs plays a key role in increasing the shelf life of fresh fruits and vegetables. [22] Figure 5 gives a brief idea of ​​the application of nano silver in food packaging. The effects of the AgNPs-PVP coating in the preservation of green asparagus have been studied successfully. [23] It was observed that the coating of AgNPs PVP slows down mass loss, ascorbic acid and total chlorophyll, reduces skin discoloration of asparagus, inhibits the increase in firmness. tissue strength, microbial growth and increased shelf life of asparagus by 10 days at 2 ºC. Similarly, the preservation of vegetables and fruits using biosynthetic AgNPs was examined by Fayaz et al. [24] The preparation of the sodium alginate membrane incorporating AgNPs was performed and its antimicrobial activity was measured, the weight loss (%) of fruits and vegetables was measured, and sensory analysis was performed. Minimum weight loss was observed in carrots and pears coated with sodium alginate film with AgNPs compared with sodium alginate coated and uncoated controls. Color, appearance, texture and taste of sodium alginate-coated carrots and pears containing AgNPs are believed to be acceptable for up to 10 days of storage compared to sodium-coated carrots and pears. alginates were uncoated and controlled. Low density polyethylene (LDPE) polymers containing AgNPs have been investigated to preserve and extend the shelf life of stored blueberries. [25] AgNPs-LDPE nano-packaging successfully maintains the organoleptic, physicochemical and physiological qualities of strawberries and strawberries at levels higher than that of conventional packaging with polyethylene bags.

2.5 Pest management

It is possible to control pests and diseases by incorporating nanoparticles into them. Silver nanoparticles act as an effective, non-toxic, safe pest management and an advanced pest control tool, and silver nanoparticle insecticides also provide high pesticide doses. for crops. [26,27] The action of silver nano-pesticides can be of great help in pest control, because in the green nanoparticle preparation method, biological agents are used to synthetic they can be bacteria or plants and the flavinoids present in plants have been shown to be toxic to plants. [28] The use of AgNPs in pest management has been reported. [29] AgNPs are used to control disease in rice weevils and herbivores. Preserved rice treated with AgNPs remained uninfected even after 2 months of treatment, so it is assumed that Ag NPs can also be used as an excellent seed protection agent.

3. Conclusion and future scope

Nanotechnology is a promising technology with the potential to make big changes in the agricultural industry. It is becoming increasingly important to agribusiness. AgNPs are recognized as potential candidates in agriculture for their remarkable traits. AgNP has been used successfully to increase crop yields, protect crops from bacterial, fungal / disease infections, and attack / infestation of pests and diseases. In addition, AgNP is used in the form of ‘nano packages’ to increase the shelf life of fresh produce such as fruits and vegetables. Currently, there is a need for studies to assess the actual impact of AgNPs on the environment and human health before they are put into production and used in many agricultural applications. Although nanotechnology is an emerging scientific field that is heavily exploited in various fields primarily electronics, energy, the environment and medicine, its application in agriculture is rarely explored. waterfall in India and abroad though it has enormous potential as a new viable tool in the agricultural sector. Solutions to unresolved field problems. This new technology will be useful in the market economically. Research in this area in India is still in its preliminary stage and also at the conceptual level to understand real-world assessments. Our farmers will benefit from such innovative use in agriculture that only we will be able to realize the use of nanoparticles in social aspects. Researchers in the nanotechnology field have a wide range of ways to use nanoparticles that intelligently prepare agricultural applications.

Reference source: Emerging Agriculture Applications of Silver Nanoparticles

Sonali K. Kale,1,* Gajanan V. Parishwad,2 Avesahemad S. N. Husainy3 and Aishwarya S. Patil4