Tomatoes get boost in growth, antioxidants from nano-sized nutrients

November 6, 2015
This image from a transmission electron microcope represents the lifecycle of the nanonutrients used in tomato plants, from seed to plant to fruit.

With the world population expected to reach 9 billion by 2050, engineers and scientists are looking for ways to meet the increasing demand for food without also increasing the strain on natural resources, such as water and energy—an initiative known as the food-water-energy nexus.

Ramesh Raliya, PhD, a , and Pratim Biswas, PhD, the Lucy & Stanley Lopata Professor and chair of the Department of Energy, Environmental & Chemical Engineering, both at the School of Engineering & Applied Science at Washington University in St. Louis, are addressing this issue by using nanoparticles to boost the nutrient content and growth of tomato plants. Taking a clue from their work with solar cells, the team found that by using zinc oxide and titanium dioxide nanoparticles, the tomato plants better absorbed light and minerals, and the fruit had higher antioxidant content.

"When a plant grows, it signals the soil that it needs nutrients," Biswas says. "The nutrient it needs is not in a form that the plant can take right away, so it secretes enzymes, which react with the soil and trigger bacterial microbes to turn the nutrients into a form that the plant can use. We're trying to aid this pathway by adding nanoparticles."

Zinc is an essential nutrient for plants, helps other enzymes function properly and is an ingredient in conventional fertilizer. Titanium is not an essential nutrient for plants, Raliya says, but boosts light absorption by increasing chlorophyll content in the leaves and promotes photosynthesis, properties Biswas' lab discovered while creating solar cells.

The team used a very fine spray using novel aerosolization techniques to directly deposit the nanoparticles on the leaves of the plants for maximum uptake.

"We found that our aerosol technique resulted in much greater uptake of nutrients by the plant in comparison to application of the nanoparticles to soil," Raliya says. "A plant can only uptake about 20 percent of the nutrients applied through soil, with the remainder either forming stable complexes with soil constituents or being washed away with water, causing runoff. In both of the latter cases, the nutrients are unavailable to plants."

Overall, plants treated with the nanoparticles via aerosol routes produced nearly 82 percent (by weight) more fruit than untreated plants. In addition, the tomatoes from treated plant showed an increase in lycopene, an antioxidant linked to reduced risk of cancer, heart disease and age-related eye disorders, of between 80 percent and 113 percent.

This illustration shows the different effects of the application of nano nutrients on a tomato plant. Credit: Ramesh Raliya, Pratim Biswas

Previous studies by other researchers have shown that increasing the use of nanotechnology in agriculture in densely populated countries such as India and China has made an impact on reducing malnutrition and child mortality. These tomatoes will help address malnutrition, Raliya says, because they allow people to get more nutrients from tomatoes than those conventionally grown.

In the study, published online last month in the journal Metallomics, the team found that the nanoparticles in the plants and the tomatoes were well below the USDA limit and considerably lower than what is used in conventional fertilizer. However, they still have to be cautious and select the best concentration of nanoparticles to use for maximum benefit, Biswas says.

Raliya and the rest of the team are now working to develop a new formulation of nanonutrients that includes all 17 elements required by plants.

"In 100 years, there will be more cities and less farmland, but we will need more food," Raliya says. "At the same time, water will be limited because of climate change. We need an efficient methodology and a controlled environment in which can grow."

Explore further: Researchers identify behaviors of nanoparticle that shows promise as nanofertilizer

More information: Ramesh Raliya et al. Mechanistic evaluation of translocation and physiological impact of titanium dioxide and zinc oxide nanoparticles on the tomato (Solanum lycopersicum L.) plant, Metallomics (2015). DOI: 10.1039/c5mt00168d

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Lex Talonis
1.7 / 5 (6) Nov 07, 2015
not rated yet Nov 07, 2015
All bullshit:


...because you've tried this and it doesn't work?
3 / 5 (2) Nov 07, 2015
It is bulshit, if we just grew organiclly we would not need to make up for the lack of nutrients. The idea that we need petroleum based fertilizers and mono cropping and factory meat farms is all profit motivated bullshit from megadeath corporations. Read the Omnivores dilemma to start then dig into it a little deeper it's always profits before people this is just like western pharmaceutical medicine, treat the symptoms not the problem, no profit in the cure just the treatment.
5 / 5 (2) Nov 07, 2015
Not BS, at least with regards to foliar spraying of various nutrients on tomato and related plants like peppers.

Weak solutions of varying amounts of magnesium sulfate, ammonium sulfates and others does enhance the growth and fruit production of the plants.

Just ask any "real" organic grower who grows these in their yard.
not rated yet Nov 08, 2015
When nano spray dries nano particles become airborne creating nanoparticle pollution. Anything below 10 microns is a lung hazard. Here are EPA air pollution standards which are being downplayed or ignored.
12 μg/m3 annual mean
not rated yet Nov 08, 2015
The mechanism described here was first laid out in my paper to the Brazil Biochar Conference 2010 and I had named the process ~'Nature's Smorgasbord' because this is precisely the way plants feed - by intelligent choice. The paper is titled 'Plant Nutrient Selection by Microbial Activation' and is available to anyone who cares to contact my email: I'm delighted to see it has been acted upon (although an attribution would have been appreciated)

Job's objection on the grounds of nano pollution have validity and I answered this in 2009 with the product Geomite - how that's done is secret

Results obtained include: silver beet with 3 metre foliage, bok choy at double size ( the latter pictured on my Linkedin profile) wheat protein increased 20% over chemical control, soil carbon sequestration up 40% in topsoil, 70% in subsoil.

Commercialisation interest in Australia: zero!

not rated yet Nov 09, 2015
Good GMOs
not rated yet Nov 10, 2015
Not BS, at least with regards to foliar spraying of various nutrients on tomato and related plants like peppers.

Weak solutions of varying amounts of magnesium sulfate, ammonium sulfates and others does enhance the growth and fruit production of the plants.

Just ask any "real" organic grower who grows these in their yard.

Yes, I agree from personal experience, foliar feeding is very effective and nano particles considered, this method above I believe would be less harmful on the micro and macro scale then our current methods.

Mostly, my panties were in a bunch after reading the article posted above as the cultured reality in which we exist is bullshit. Around 120 corporations pull the strings on the world and as they go we go.

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