Nanotechnology in Agriculture

Advances in agriculture are always being made to ensure that the food output can meet the needs of an ever-growing population. Given that many people outside of the scientific industry have a phobia that nanomaterials aren’t safe, you’d expect that applications which deal with foodstuffs to be low on the list of application areas where nanotechnology is having an impact. However, there are in fact many different nanomaterials that are being tested and applied across different agricultural areas.

As general class of materials, the aim of using nanotechnology in the agricultural sector is to reduce the application of plant protected products, minimize nutrient loss during fertilisation, and increase the yield of crops by optimising their nutrient intake. There are also many different sub-applications for nanotechnology in agriculture. For example, these include using nanomaterials in biochemical sensors to detect the interactions between enzymes and foodstuffs, the development of nanocapsules which provide an effective and controlled delivery of fertilisers, pesticides, growth hormones, and other agrichemicals to specific sites of interest to prevent the over application of agrichemicals, nanosensors which can monitor the conditions of the soil and the growth of the crops and detect whether there are any animal or plant pathogens in the crop, nanochips which can be used for identity preservation and tracking of crops, and the development of nanoparticles which are designed to deliver DNA to plants—which are used as part of a targeted genetic engineering approach.

However, not all these areas have been realised commercially, yet. But there are some. The increase of information from nanosafety and regulatory-focused projects in recent years is helping with the commercialisation of nanotechnology in the agricultural sector. Where many people have thought that nanomaterials would end up in foodstuffs and in the local ecosystems, the more that these projects are being undertaken, the more people are realising that the potentially toxic effects are not as bad as first thought (although this cannot be said for all nanomaterials, as each one is different). As it stands, the cost of developing products that contain nanomaterials is quite high compared to other chemicals, so commercially, most products that use nanomaterials on the market are soil-enhancers which promote even water distribution and storage (and therefore the distribution of nutrients contained within the water).

We can also look at a couple of specific nanomaterials that are have been undergoing testing in recent years. The first is carbon nanomaterials, in particular, different carbon nanotubes (CNTs). CNTs have been trialled for a number of uses within the agricultural sector. One of these areas is for boosting the growth of fruits from seeds, and some initial trials have shown that CNT-treated seed germinate quicker and produce larger and heavier seedlings compared to non-treated seeds. It is thought that this happens by facilitating a greater uptake of water in to the seeds, which makes them grow more. Other applications of CNTs in agriculture include removing contaminants from different plants, targeted delivery of nutrients, and in different sensors which are designed to monitor the humidity and carbon dioxide concentrations in controlled greenhouse environments, as well as in the pressure sensors used in the agrichemical spraying equipment.

Another material that could have widespread use is the silver nanoparticle, and a lot of future developments will depend on further studies that show how silver nanoparticles migrate in various scenarios. Because silver nanoparticles are known to have high antimicrobial properties, their application in agriculture varies from carbon nanomaterials. Most of the tests have been around their antimicrobial, antiviral, and antifungal effects against various diseases, viruses, and fungi that can harm plants. As well as diseases, the use of silver nanoparticles has also been trialled for killing pests that cause harm to some plants. In many trials, the silver nanoparticles have found to be

effective against the intended target and are also seen as an efficient way of stimulating plant growth.

Some other nanomaterials that are being trialled for agricultural uses include nano-copper (antimicrobial uses), silica nanoparticles (targeted delivery and genetic manipulation), nano-iron (curing infections in plants), chitosan nanoparticles (antimicrobial uses), and liposomes (targeted delivery). So, we may start to see more nanomaterials being used in the agricultural industry in the future.