Nanotechnology: Applications in Agriculture

https://www.youtube.com/watch?v=rNMCbdmHvaE

Nanotechnology : Applications in Agriculture (PowerPoint Presentation)

NanotechnologyAgriculture

Smart Nanofertilizers for Agriculture

Smart Nanofertilizers

Mineral nutrients  such as nitrogen, phosphorous potassium, calcium, magnesium, sulphur, and other micronutrients are essential for plant growth and crop production.  Presently, we face a glaring contrast of insufficient use of nutrients on one hand and excessive use on another. Nutrients Use efficiency (NUE) represents a key indicator to assess progress towards better nutrient management. Fertilizers are chemical compounds applied to promote plant growth. It is applied either through the soil or by foliar feeding. Artificial fertilizers are inorganic fertilizers formulated in approximate concentration to supply the nutrients. Nitrogen is an important source which is essential for the growth of plant. Urea is the most wildly used water soluble plant nitrogen source. Due to leaching the nitrogen content in the soil get decreased leading to low nitrogen utilization efficiency.

Nitrogen-use efficiency for most crops ranges from 30 to 50 percent, so researchers are developing intelligent nano-fertilizers to reduce the amount of nitrogen lost during the crop production.  The plant needs different amount of nitrogen depending on its growth stage. A new generation of fertilizers will increase this efficiency from 30 percent to upwards of 80 percent. The idea is to develop a product that will release nitrogen only when the plant needs it and in the amount the plant needs. The plants communicate their surroundings environment by producing all kinds of chemical signals. A plant synthesizes specific compounds to communicate with specific microbes. The microbes then go to work and free nitrogen that the plant uses to grow. Thus, roots send out signal that ask microbes to transform nitrogen in the soil into a chemical form the plant can use. Many chemical compounds that are associated  with nitrogen uptake have been identified. These compounds can be used to synchronize the release of fertilizer with nitrogen uptake by the crop. 

A biosensor is a device that combines a biological recognition element with a physical or chemical transducer to detect a biological product. In other words, it is a probe that integrates a biological one with an electronic component to yield a measurable signal. Several biosensors are being developed for different applications. Typically a biosensor consists of three components: the biological recognition element, the transducer and the signal processing electronics. Nano-biosensors that will bind to these compounds can be developed so as to control of the release of fertilizers. The polymers coatings that protects the fertilizers from the elements contains nano-sized biosensors which are made up of very specific chemical compounds that allow the fertilizers to be released into the soil when the plant needs it. These biosensors know when to release nitrogen because they are able to detect chemical signals released from the roots of the plant to the soil. Biosensors can detect when a plant requires more nitrogen and allow microbes access to the fertilizer-nitrogen inside the polymer protected particles. 

Each plant species sends out its own variety of chemical signals. Keeping this concept in mind, a smart nano-fertilizer product could be tailored to respond differently to the needs of different crops. For instance, the nitrogen particles could be designated to become available to wheat, but not to the canola growing in the same field because of different compounds emitted by different crops. We can prepare different biosensors using different compounds and tailor the fertilizers to each different crop for different climatic zones and soils. Dr. Carlos Montreal of Agriculture and Agri-Food Canada in Ottawa is one of the several research scientists developing a fertilizer that responds to organic compounds emitted by a plant’s roots. The research team is trying to make  intelligent fertilizers with the biodegradable three-dimensional polymer coating less than 100 nm  thick. Hence, in coming years farmers could have access to an intelligent nano-fertilizers  that synchronizes the release of nitrogen with crop uptake.

Smart and Intelligent Nano-Fertilizers

Nanotechnology for developing smart and intelligent Nano-Fertilizers. 

http://www.biotecharticles.com/Nanotechnology-Article/Intelligent-Nano-Fertilizers-3544.html

Nanotechnology in Agriculture : Future Prospective

Nanotechnology  in Agriculture

The use of nanomaterials for delivery of pesticides and fertilizers is explored to reduce the dosage and ensure controlled slow delivery but the risk assessment of the use of nanomaterials is still not defined. Toxicity of the ecosystem, potential residue carry-over in foodstuff and nanomaterials phytotoxicity are some of the major concern for application of nanomaterials in agriculture. The health concern of nanomaterials has been reviewed . There is need to evaluate the toxicokinetics and toxicodynamics of nanomaterials used in agricultural production. Nanomaterials owing to increased surface area might have toxic effects that are not apparent in the bulk materials especially in open agricultural ecosystem. The selection of nanomaterials for application in the field may be critical as materials which are non-toxic, biodegradable and biocompatible are desirable. Nanofabrication with hyper-accumulator plant or in combination with soil microorganism will provide the approach of “Designer plant” boosting up the nutrient uptake and phytomining efficiency.  This can be achieved in future by nano-biofarming or particle farming. This is one such field which yields nanoparticles for industrial use by growing plants in defined soil.

Smart precision farming will make use of computers, global satellite positioning system and remote sensing devices to measure highly localized environmental conditions enabling us to know whether crops are growing at maximum efficiency. Nanotechnology may be developed and deployed for real-time monitoring of the crop growth and field conditions including moisture level, soil fertility, temperature, crop nutrient status, insects, plant diseases, weeds. Networks of wireless nanosensors positioned across cultivated fields will provide essential data leading to best agronomic intelligence processes with the aim to minimize resource inputs and maximize output.

Humidity, light temperature, soil conditions, fertilization, insects, and plant diseases all affect the release of volatile organic compounds which could be detected by electronic nose. Electronic noses in agriculture will detect crop diseases, identify insect infestation, and monitor food quality. The electronic nose could also be used in food industry to assess the freshness spoilage of fruits and vegetables during the processing and packaging process. Smart dust technology will be used for monitoring various parameters such as temperature, humidity, insect and disease infestation in future. This is the future of agriculture, an army of nanosensors will be scattered like dust across the farms and fields, working like the eyes, ears and nosed of the farming world. These tiny wireless sensors are capable to communicate the information they sense. These will be programmed and designed to respond various parameters like variation in temperature, nutrients and humidity.

In summary, the development of nanomaterials with good dispersion and wettability, biodegradable in soil, and environment, less toxic and more photo-generative, with well understood toxicokinetics and toxicodynamics, smart and stable, and ease of fabrication and application in agriculture, would be ideal for their effective use in agricultural crop production. 

Nano-Foods

Nanofood is defined as the food derived from the use of nanotechnology techniques or tools during cultivation, production, processing or packaging. After harvesting, crop is processed and then it reaches to consumers in the form of food. One common problem encountered in food sector is that it loses its freshness and quality before reaching to the consumers. Generally food contains bacteria and viruses which ends in illness and sometimes fatality. Nanotechnology can play an important role by designing smart biosensors that can be packed along with the food material. These smart biosensors will warn the consumers about the freshness of the food by colour change indicators. So if there is large concentration of bacteria in a particular food, the biosensor will produce a strong signal indicating the food as unsafe to eat. Biosensors developed on the basis of nanotechnology can detect pathogen in the food matrices. Multifunctional FeO NPs with their surface attached to antibodies can specifically bind to the microorganism can be used for their detection in complex food matrices.

A major problem in food science is determining and developing an effective packaging material. Quality and freshness of food can also be maintained by designing smart packaging materials using nanotechnology to keep the food fresh for longer duration. In addition, many companies are also adding NPs to dietary supplements to enhance their bioavailability and efficacy. Nutraceuticals like lycopene, beta-carotene, lutein, phytosterols, have been incorporated into nanosize self-assembled liquid structures to deliver nutrients to cells. Food and cosmetic companies are working together to develop new mechanism to deliver vitamins directly to the skin.

Nanotechnology may provide solutions to nanoscale biosensors for pathogen detection and to delivery systems for bioactive ingredients in foodstuffs through improved knowledge of food material and their uptake at the nanoscale. Consumers need to be aware of the risk that nanofood may suffer the destiny as genetically modified (GM) crops. Products developed by using nanotechnology are flooding the market in food industry. But there are no specific rules and regulations to check their risks.

A number of factors contribute to a demand for the traceability of food throughout production, processing, distribution and consumption. Nanotechnology based tracing devices can integrate multiple functional devices that provide other important information such as sensors for detection of the presence of pathogens, spoilage microorganism, allergen, chemicals, and other contaminants in food as well as nutritional information. Nanoscale tagging devices can be used to record and retrieve information about the product history. These types of applications will help producers, retailers and consumers regarding food safety. 

Nano-Biosensors

    A biosensor is a device that combines a biological recognition element with a physical or chemical transducer to detect a biological product. In other words, it is a probe that integrates a biological one with an electronic component to yield a measurable signal. Several biosensors are being developed for different applications. Typically a biosensor consists of three components: the biological recognition element, the transducer and the signal processing electronics and functions at five different levels:

•        Bioreceptor that bind the specific form to the sample
•       Electrochemical interface where specific biological processes occur giving rise to a         signal
•       A transducer that converts the specific biochemical reaction in an electrical signal
•       A signal processor for converting the electronic signal into a meaningful physical            parameter 
•       A proper interface to display the results to the operator

    Various nanomaterials have been used in biosensors technology to produce nanobiosensors. Various nanomaterials are implemented either into transducers or receptors operation parts, so as to enhance their multidetection capability and sensitivity. These nanomaterials are nanoparticles, nanotubes, quantum dots (QDs) or other biological nanomaterials. These nanomaterials can contribute to either the bio-recognition element or the transducer or both, of a biosensor. Nanoparticles-based biosensor are particularly attractive because they can be easily synthesized in bulk using standard chemical techniques. Biosensors may be classified according to the mechanism of biological selectivity (bioreceptor) otherwise, on the mode of physiochemical signal transduction (transducer). Bioreceptor is a molecular species that exploits a biochemical mechanism of recognition. They are accountable for binding the concerned analyte to the sensor for measurement. Bioreceptor can broadly be classified into five distinct classes. These classes comprise antibody-antigen bioreceptor, enzymatic bioreceptor, nucleic acids (DNA) bioreceptor, cellular bioreceptor, biometric bioreceptor and bactriophage bioreactor. The transducer plays a crucial part in the detection and identification process of a biosensor. The transduction methods such as optical, electrochemical and mass based are the most favored and universal method.

Surface plasmon resonance (SPR) is a robust tool that can measure the binding kinetics of two molecules without the help of any fluorescent tag. Thus, this technique can be said as peculiarity that appears during optical illumination of a metal surface and can be adopted for biomolecular interaction analysis. The advantages affiliated with this are that it takes less time to detect binding events since it is label-free, it excluded additional reagents, assays and steps. Aptamers are those which work with the principle of target specific binding with high affinity, they are single stranded nucleic acid, they fit for the target in all the way forming three dimensional with strict bonding can be produced in vitro.  This kind of nanosensors gives more specific and effective detecting plant diseases, crop resistance and yield production.

Smart dusts are the devices made up of micro sized electro chemical sensors contained in it.  It works on three principles, sensing, processing and computing. This technology gains popularity in a way of its operations. It can be monitored with wireless radios, transducer irrespective of location of sensor, its size is very small due to which it can be undetectable. Major power of sensing itself to the environmental changes, automation and computing has made it come to greater extent. Smart dust technology could be used for monitoring various parameters such as temperature, humidity, insect and disease infestation, but still there are major drawbacks faced by this technology like the impact on environment, toxicity.

             Electronic nose (E-nose) consists of an array of gas sensors  which are composed of NPs e.g. ZnO nanowires with a broad and partly overlapping selectivity and an electronic pattern recognition system with multivariate statistical data processing tools. Their resistance changes with the passage of the certain gas and generate a change in electrical signal that form the fingerprint pattern for gas detection. This pattern is used to determine the type, quality, and quantity of the volatile organic compounds being detected. Plants release volatile organic compounds as a byproduct of everyday physiological processes and these specific compounds and the quantities release are indicative of both the crop and field conditions.