Nano Technology by NANO Hydroponics
NANO Technology
A 'New Age Nutrient Order'?
There has been a lot of research on nano particles over the last 16 years, but only recently (2008) has there been research on nano particles and the influence on plants, something we will refer to as Phytonanotechnology. Questions such as the following will be looked at;
What benefits will phytonanotechnology have?
Will there be negative associations such as bioaccumulation?
What impact will phytonanotechnology have on the environment?
What is the future for phytonanotechnology?
These are some of the questions we aim to answer in this article because with a relatively new technology, these types of concerns are often raised, but we shouldn't let these innate concerns cloud judgement, so we're going to let the science do the talking instead.
Introduction:
Nanoparticles are particles that are anywhere between 1 and 100 nanometers in size. To give this some comparison, you could fit 1 million nanoparticles (1nm) into this full stop here. A typical nanoparticle of fertiliser will be between 10-20 nm so you could fit between 50,000 and 100,000 nanoparticles of this size into this full stop. You could also fit 100,000 nanoparticles into the width of a human hair... Nano particles are incredibly small and it's a small miracle that we have learnt to manipulate and adapt them to cover a wide range of beneficial products. The reason they offer exciting advances in horticulture as well as other industries is because at the nano level, molecules will act differently to their larger bulky counterparts and have unique physiochemical properties such as smaller size, chemical composition, surface structure, stability and shape.
Some of the areas that nanoparticles are currently used include; Automobiles (made lighter), clothing (Stain resistance), Sunscreen (Increased UV protection), surgery (Synthetic bones made stronger), mobile phones (Lighter materials), glass packaging for drinks (Longer shelf life) and in sports (durable equipment such as tennis and golf balls).
What are they doing in horticulture though?
The research in horticulture has been varied and consistent over the past 8 years, the main nano particles being tested for horticultural viability include Iron (Fe3O4), Silica (SiO2), Cobalt ferrite (CoFe2O4), Titanium oxide (TiO2), Zinc oxide (ZnO), Copper oxide (CuO) along with gold and silver nanoparticles (Au and Ag). There are many more being investigated but those were the elements with the most amount of research around them.
Iron (Fe3O4) has had a lot of research recently, one study by Zhu et al. (2008), showed that the nanoparticles are directly taken up and translocated in pumpkin (Curcurbita maxima) with no toxic effects at concentrations of 0.5g/l (1).
Silica (SiO2) has had good work done by Slomberg (2012) showing silica nanoparticle phytotoxicity to Arabidopsis thaliana, a popular plant model for plant biology and genetics, no toxicity was found at doses of 1000mg/l (2).
Phytonanotechnology advances and advantages
The benefits of phytonanotechnology are wide and varied according to the research that's been conducted so far. Phytonanotechnology can deliver fertilisers, pesticides and herbicides to targeted sites and be released on-demand for nutritional needs or pest protection, this would reduce the requirement for repeated application of fertiliser/pesticide/herbicide and therefore reduce the negative affects on the environment. A recent review of nanotechnologies in plant sciences by Wang et el. (2016) says that phytonanotechnology can;
1) Reduce applications of plant-protection products
2) Decrease nutrient losses from fertilisers
3) Increase yields through optimised nutrient management (3).
The most important aspect for commercial growers is the increased yield due to the lower energy required by the plant to uptake nutrients. The nanoparticles are so small they require very little to no energy from the plant via active transport to pull the nutrients into the vascular system, the plant therefore has more energy for other processes such as fruit/root/flower formation and production.
One of the benefits with nano Iron (Fe3O4) through leaf tissue analysis was the increased uptake of other nutrients when using nanoparticles. The reason is thought to be because of the increased chlorophyll production in the leaf which increases the amount of light harvested and therefore the bigger nutrient requirement, the leaf tissue analysis saw an increase of Nitrogen, Phosphorous, Potassium, Calcium, Magnesium and other micro elements compared to a control without nanoparticles.
Observational studies have shown an increase in oil production in the tobacco plant when using Iron (Fe3O4), although this needs further testing and analysis to confirm findings. Over the coming years, there will undoubtedly be a plethora of benefits coming from phytonanotechnology, but there are concerns over the effect to the environment and the living species within it.
Phytonanotechnology concerns
One of the concerns about phytonanotechnology is the effect of bioaccumulation in plant material being passed to herbivores, insects, birds and carnivorous animals. If the nanoparticles accumulated and were eventually consumed by humans, what impact would this have on the food chain and humans' health?
This question has been looked at by numerous studies (4, 5, 6 and 7), the nano particles studies were Au (gold), CeO2 (Cerium Oxide) and La2O3 (Lanthanum oxide). What the studies show is that although they did not find biomagnification of nanoparticles there was some trophic transfer, therefore human exposure to nanoparticles via food dietary uptake or food chain contamination needs to be considered when these phytonanotechnologies are developed. This trophic transfer is very good news when developing nano particles to correct deficiencies such as iron deficiency anaemia, but also shows we need to be careful about what nanoparticles are used and how much research has been conducted before using them.
The environment
Research by Scherzinger (2008) (8), said in an article that, in essence, current nanoparticles pose very little risk to the environment, possible problematic nanoparticles require further research but ultimately to make a defined statement we need to assess all nanoparticles as they will have different effects depending on size, composition and surface treatment. The current phytonanotechnology research and product availability is on Iron and Silicon, Fe3O4 and SiO2 respectively. Due to their source material coming from natural sources, there will be no detrimental effects to ecosystems and the natural environment. However, future phytonanotechnology may require more research and testing before being used in agriculture or hydroponics.
The future of phytonanotechnology
The future for nano technology in horticulture is promising, it can present revolutionary ways of increasing crop yield, health and human nutrition along with safer methods of applying pesticides and herbicides. As a relatively new technology though, researchers and scientists must look further into toxicity and trophic transfer of nano particles, in environments that are similar to those that they will be used in, to establish wide acceptance by the public and to reduce the innate fear that people can have with new technologies such as this. To conclude on a positive note, current research on potato’s have shown dramatic increases of nano Iron, Calcium and Zinc in potatoes. This could potentially lead to reductions in diseases such as iron-deficiency anaemia in lower economically developed countries.
The future for nano technology in horticulture (phytonanotechnology) is extremely promising and we’ll hopefully be looking back at this article in a couple of years time with a whole host of innovate nano products… Time will tell.
Visit this website for current Nano technology product for Hydroponics and horticulture.
www.nanohydroponics.co.uk
References:
(1) Zhou, H. et al. (2008) Uptake, translocation, and accumulation of manufactured iron oxide nanoparticles by pumpkin plants. J. Environ. Monet. 10, 713-717
(2) Slomberg, D.L and Schoenfisch, M.H. (2012) Silica nanoparticle phytotoxicity to Arabidopsis thaliana. Environ. Sci. Technol. 46, 10247-10254
(3) Wang, P. et al. (2016) Nanotechnology: A new opportunity in plant sciences. Trends in plant science. TRPLSC. 1423, 1-14
(4) Judy, J.D et al. (2012) Bioaccumulation of gold nano materials by manduca sexta through dietary uptake of surface contaminated plant tissue. Environ. Sci. Techno. 46, 12672-12678
(5) Unrine, J.M et al (2012) Trophic transfer of Au nanoparticles from soil along a simulated terrestrial food chain. Environ. Sri. Techno. 46, 9753-9760
(6) Hawthorne, J. et al. (2014) Particle-size dependant accumulation and trophic transfer of cerium oxide through a terrestrial food chain. Environ. Sci. Technol. 48, 13102-13109
(7) De la Torre Roche, R. et al. (2015) Terrestrial trophic transfer of bulk and nanoparticle La2O3 does not depend on particle size. Environ. Sci. Technol. 49, 11866-11874
(8) Scherzinger, M. (2008) Nanoecotoxicology: environmental risks of nanomaterials. Nat. Nanotechnol. 3, 322-323