Agriculture Reference
In-Depth Information
nanopowder (40-100 nm in thickness) were studied as a coating for urea (Liang and
Liu
2007
). In another example, polystyrene mixed with nano-kaolin formed com-
posites with 10-20 nm pores. When blended with urea and tested as seed coatings
on winter wheat seeds, no adverse effects on germination were noted. Studies on the
leaching of nitrogen from these composites showed that nitrogen release was slower
than if the fertilizer was applied uncoated (as low as 56 % released in 40 days for the
composite compared to 90 % from the fertilizer alone). Overall crop yield was seen
to increase by up to 27 % compared to controls (Hussein et al.
2002
).
All the patents and patent applications whose inventions fall under Category
3 can be found in Table
2.3
, once again grouped in terms of their nano-content.
Several examples are cross-listed to multiple categories.
2.2.4 Commercial Products from All Three Categories
Despite the relative infancy of the field of nanofertilizer inputs, there are several
examples of products currently available on the market that claim some form of
nanotechnology in their formulations (
www.agro-genesis.com
, accessed December
28, 2013;
www.ngtech.com.au
, accessed December 28, 2013;
www.nafertino.com.
tw/en
, accessed January 11, 2014;
www.stratbizworld.com
,
accessed January
11, 2014). In many cases, very little detail about the “nano” nature of the fertilizer
product is provided. In some cases, however, it is clear that the term “nano” in these
products is used very informally; no nanoparticles or nanomaterials appear to be
incorporated in the product. For example, Nano-Gro (
www.agronano.com
,
accessed December 21, 2013) contains nanomole amounts of iron, cobalt, magne-
sium, and manganese mixed with pharmaceutical grade sugar. The products,
claimed to be “homeopathic plant medicine,” are based on a concept that
“a biologically active substance in very low concentrations triggers a high con-
centration response.” Other products appear to contain nanomaterials, but the
composition of the nanomaterials or the processes by which they are prepared are
unclear. An example of this is the Chinese product “Silicon23 +Microbes NPK”
accessed January 4, 2014). This fertilizer appears to be silica- or silicate-based
nanoparticles. The Silicon23 +Microbes NPK fertilizer website states that it is a
“microbes-silicate-based fertilizer containing a high content of essential elements
and microbes using the latest nanotechnology.” Calcium carbonate nanoparticles
prepared by an ultrahigh-speed shearing technique called “nanotechnological
tribodynamic activation” are the main component of a product named Lithovit
high-yield fertilizer (
www.lithovet.net
, accessed January 4, 2014). The mechanism
of action of this foliar fertilizer is to increase CO
2
levels in the leaves, leading to an
increase in photosynthesis and higher crop yields. NanoNB is a fertilizer product
from the UK company NanoVapor Technologies. They claim on their website that
it is based on a blend of humified organic material and that it has plant growth
stimulation properties. No other details are provided about the product. Their other
