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Smart Fertilizers as the Best Option for Ecofriendly Agriculture
Dr. M. Ranjith1* and Dr. S. Sridevi2
*1Research Associate, ICAR-Central Research Institute for Dryland Agriculture
Santoshnagar, Hyderabad, Telangana state 2Principal, Agricultural Polytechnic, Tornala, PJTSAU, Siddipet, Telangana State
Corresponding Author
Dr. M. Ranjith
Email: [email protected]
Keywords
Smart fertilizers, Slow release fertilizers and Ecofriendly agriculture
How to cite this article:
INTRODUCTION
griculture plays a pivotal role in the
Indian economy. India holds the
second largest agricultural land (179.9
million ha) and agriculture accounts for 13.7%
of the GDP and provides employment to 56%
of the Indian workforce (Indiastat.com). Thus
agriculture not only contributes to overall
growth of the economy but also reduces poverty
by providing livelihoods and food security to
the majority of the population in the country
and thus it is the most inclusive growth sector
of the Indian economy. During the green
revolution period, new varieties were created to
produce higher yields in conjunction with the
intensive use of chemical fertilizers and
irrigation (Bowonder, 1979). The amounts of
A
ABSTRACT
As world population increase, there will be increasing pressure on global food systems and
agriculture. In the coming days, will have the challenge to providing sufficient food for a
growing population without impacting the environment will be a challenge. Accordingly,
it will be imperative to use modern technologies in agro ecosystems in order to supply
adequate food and minimize the negative impacts on the environment induces by chemical
fertilization and by inadequate recycling of farm wastes. There is an urgent to revolutionize
the agricultural systems with combination of biotechnology and nanotechnology and find
sustainable solutions for current and future problems. These include the development and
use of smart fertilizers with controlled/slow nutrient release, together with bioformulations
based on bacteria or enzymes. The importance of smart fertilizer development and use in
future food production and advances in the development of slow/controlled released
fertilizers and use of harvesting residues as coating and carrier materials for ecofriendly
agriculture are discussed in this article.
OPEN ACCESS
Ranjith, M. and Sridevi, S. 2021. Smart Fertilizers as the Best Option for Ecofriendly Agriculture.
Vigyan Varta 2(1): 51-55.
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chemical fertilizers used post-advent of the
green revolution continued to increase (Fig. 1).
The overuse of chemical fertilizers to get high
yield causes physical and chemical degradation
of the soil by altering the natural microflora and
increasing the alkalinity and salinity of the soil
(Singh, 2000).
Fig: 1. Consumption of fertilizers (N, P and K)
post-green revolution period (DAC & FW,
2017)
Returns from investment on fertilizer have been
declining over time, even as the cost of
fertilizers and crop production overall are
escalating. It has become more important than
ever befor to use chemical fertilizers
judiciously and to explore innovations related
to smart fertilizer technology as a response to
food security concerns under growing global
population and the environmental impacts of
current agricultural systems. Smart fertilizers
may be a solution to enhance food production
and environmental quality.
Slow/controlled released fertilizers
According to Shaviv (2005): “The term
controlled - release fertilizer (CRF) became
acceptable when applied to fertilizers in which
the factors relating to the rate, pattern and
duration of release are well known and
controllable during CRF preparation.” Slow
release fertilizers (SRFs) involve the release of
the nutrient at a slower rate than is usual but the
rate; pattern and duration of release are not well
controlled. Microbially decomposed N
products, such as urea-formaldehydes, are
commonly referred to as slow-release
fertilizers, and coated or encapsulated products
as controlled-release fertilizers (Trenkel, 1997).
The possible delay in initial availability of
nutrients or consistent supply for extended time
periods is achievable through a number of
mechanisms. These mechanisms include semi-
permeable coatings for controlled solubility of
the fertilizer in water, protein materials,
occlusion, chemicals, slow hydrolysis of water
soluble compounds of lower molecular weights
and some other unknown means (Naz and
Sulaiman, 2016). Many coating materials can
be used to slow nutrient release, including
natural materials such as clays and nanoclays
(e.g., allophane) and nondegradable
(polysulfone) and biodegradable polymers
(e.g., alginate
beads). Several studies have shown that urea-
based coatings can have variable efficiencies
depending on the material used (Du et al.,
2006).
Fig: 2. Schematic representation of smart
fertilizer effects in soil-plant system
Bioformulations and Plant Growth
Promoting Rhizobacteria (PGPR)
Plant growth promoting rhizobacteria (PGPR)
are a heterogeneous group of bacteria that can
be found in the rhizosphere, at root surfaces and
in association with roots, which can improve
the extent or quality of plant growth directly
and or indirectly. The exact mechanisms by
which PGPR promote plant growth are not fully
understood, but are thought to include (i) the
ability to produce or change the concentration
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of plant growth regulators like indoleacetic
acid, gibberellic acid, cytokinins and ethylene
(ii) asymbiotic N2 fixation (iii) antagonism
against phytopathogenic microorganisms by
production of siderophores, antibiotics and
cyanide (iv) solubilization of mineral
phosphates and other nutrients (Ahmad et al.,
2008). The environmental factors include
climate, weather conditions, soil characteristics
or the composition or activity of the indigenous
microbial flora of the soil. To achieve the
maximum growth promoting interaction
between PGPR and nursery seedlings it is
important to discover how the rhizobacteria are
exerting their effects on plant and whether the
effects are altered by various environmental
factors, including the presence of other micro-
organisms (Bent et al., 2001). In the last few
decades, a large array of bacteria including
species of Pseudomonas, Azospirillum,
Azotobacter, Klebsiella, Enterobacter,
Alcaligens, Arthobacter, Burkholderia,
Bacillus and Serratia have been reported to
enhance plant growth.
1. Nano fertilizers
Nano fertilizers increase the nutrient use
efficiency by 3 times and also provide stress
tolerating ability. Irrespective of the type of
crop, nano technology can be used. Since nano
fertilizers contain nutrients and growth
promoters encapsulated in nano scale polymers,
they will also have a slow and a targeted
efficient release (Sadik et al., 2009). A nano-
fertilizer refers to a product in nanometer
regime that delivers nutrients to crops. For
example, encapsulation inside nanomaterials
coated with a thin protective polymer film or in
the form of particles or emulsions of nanoscale
dimensions (De Rosa et al., 2010). Surface
coatings of nanomaterials on fertilizer particles
hold the material more strongly due to higher
surface tension than the conventional surfaces
and thus help in controlled release. Delivery of
agrochemical substance such as fertilizer
supplying macro and micronutrients to the
plants is an important aspect of application of
nanotechnology in agriculture. Excessive use of
nitrogenous fertilizer affects the groundwater
and also causes eutrophication in aquatic
ecosystems. A disturbing fact is that the
fertilizer use efficiency is 20-50 per cent for
nitrogen and 10-25 per cent for phosphorus.
With nano-fertilizers emerging as alternatives
to conventional fertilizers, build-up of nutrients
in soils and thereby eutrophication and drinking
water contamination may be eliminated. In fact,
nano-technology has opened up new
opportunities to improve nutrient use efficiency
and minimize costs of environmental protection
(Manjunatha et al., 2016).
2. Use of Harvesting Residues for Smart
Fertilizer Formulations
Low-cost materials such as wheat straw are
abundantly available resources in current
agricultural systems (Jiang et al., 2012). These
harvesting residues contain lignin,
hemicelluloses, and cellulose (Hubbe et al.,
2010). Wheat straw contains surface carboxyl,
hydroxyl, ether, amino, and phosphate, which
enhance its reactivity and physicochemical
properties, useful in the preparation of
adsorbent materials for the treatment of
wastewater and slow-release fertilizers (Liu et
al., 2013). Xie et al. (2011) noticed the potential
use of wheat straw for the development of slow-
release N and boron fertilizers with water-
retention properties.
Harvesting residues, such as straw, may also be
used as feedstock for energyproducing
pyrolysis systems with biochar generation.
Considering its physicochemical properties,
carbonaceous materials like pyrogenic carbon
(biochar) have been widely used as soil
ameliorant with several applications in both
laboratory and field studies (Wiedner et al.,
2015). Biochar is obtained through pyrolysis of
agricultural or other lignocellulosic biomass at
temperatures ranging from 350°C to 700°C.
Biochar was found to increase the C
sequestration potential of soil through its high
stability and the reduction of native soil OM
mineralization (Naisse et al., 2015). The use of
biochar as carrier for smart fertilizers could be
highly beneficial, as it combines nutritional
benefits for plants with improvement of many
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other soil functions due to the addition of
biochar itself. In particular, biochar addition to
soils has positive effects on water-holding
capacity as well as C sequestration. However,
biochar properties vary widely depending on
feedstock and production conditions (Wiedner
et al., 2013).
CONCLUSIONS:
In order to meet sustainable development goals,
agricultural production needs to be increased
and the pollution and GHG emissions related to
farming activity need to be decreased.
Advances in the application of biotechnology
and nanotechnology have the potential to
facilitate improved nutrient management and
use efficiency in agroecosystems. Compared
with conventional fertilizers, smart fertilizers
such as slow/controlled release,
bioformulations and harvesting residue have
been shown to improve crop yields, soil
productivity, and lower nutrient loss. Several
materials such as clays, nanoclays,
nondegradable and degradable polymers, and
agricultural wastes are suitable for the
development of smart fertilizers by acting as
carrier matrices for nutrients and bacterial
inoculants. We suggest that organic wastes
occurring as harvesting residues in agricultural
systems should be used in the sense of a circular
economy to create innovative fertilizers from
natural materials, which are urgently needed to
ensure sustainable intensification of
agricultural systems.
REFERENCES:
Ahmad, F., Ahmad, I., Khan, M.S., 2008.
Screening of free-living rhizospheric
bacteria for their multiple plant growth
promoting activities. Microbiol. Res.
163, 173–181.
Bent, E., Tuzun, S., Chanway, C.P., Enebak, S.,
2001. Alterations in plant growth and
in root hormone levels of lodgepole
pines inoculated with rhizobacteria.
Can. J. Microbiol. 47, 793–800.
Bowonder B. Impact analysis of the green
revolution in India. Technol Forecast
Soc Chang. 1979; 15: 297–313.
Department of Fertilizers and Department of
Agriculture, Cooperation & Farmers
Welfare (DAC&FW). India. 2017.
De Rosa, M. R., Monreal, C., Schnitzer, M.,
Walsh, R. and Sultan, Y., 2010.
Nanotechnology in fertilizers. Nat.
Nanotechnol. J., 5: 91-96.
Hubbe, M., Nazhad, M., Sa´nchez, C., 2010.
Cellulosic biomass and organic waste
into high value soil amendments: a
review. BioResources 5 (4), 2808–
2854.India stat.com/agriculture:
https:// www.indiastat. com/
agriculture- data.
Jiang, D., Zhuang, D., Fu, J., Huang, Y., Wen,
K., 2012. Bioenergy potential from
crop residues in China: availability and
distribution. Renew. Sustain. Energy
Rev. 16, 1377–1382.
Liu, J., Su, Y., Li, Q., Yue, Q., Gao, B., 2013.
Preparation of wheat straw based
superabsorbent resins and their
applications as adsorbents for
ammonium and phosphate removal.
Bioresour. Technol. 143, 32–39.
Manjunatha, S.B., Biradar, D.P., Aladakatti,
Y.R., 2016. Nanotechnology and its
application to agriculture: a review. J.
Farm. Sci. 29 (1), 1–13.
Naisse, C., Girardin, C., Lefevre, R., Pozzi, A.,
Maas, R., Stark, A., Rumpel, C., 2015.
Effect of physical weathering on the
carbon sequestration potential of
biochars and hydrochars in soil. GCB
Bioenergy. 7, 488–496.
Naz, M.Y., Sulaiman, S.A., 2016. Slow release
coating remedy for nitrogen loss from
conventional urea: a review. J. Control.
Release 225 (10), 109–120.
www.vigyanvarta.com Vol-2 Issue-1 Ranjith and Sridevi (2021)
55 | P a g e
Popular Article
Sadik, O. A., Zhou, A. L., Kikandi, S. N., Du,
Q., Wang and Varner, K., 2009,
Sensors As Tools For Quantitation,
Nanotoxicity and Nano Monitoring
Assessment of Engineered
Nanomaterials, J. Envir. Monit., 287-
294.
Shaviv, A., 2005. Controlled Release
Fertilizers, IFA International
Workshop on Enhanced-Efficiency
Fertilizers, Frankfurt. International
Fertilizer Industry Association, Paris,
France.
Singh R.B. Environmental consequences of
agricultural development: a case study
from the green revolution state of
Haryana, India. Agric Ecosyst Environ.
2000: 82 (1–3): 97–103.
Trenkel, M.E., 1997. Improving Fertilizer Use
Efficiency: Controlled-Release and
Stabilized Fertilizers in Agriculture,
The International Fertilizer Industry
Association, Paris. International
Fertilizer Industry Association (IFA),
Paris, France, p. 151.
Wiedner, K., Rumpel, C., Pozzi, A., Maas, R.,
Steiner, C., Glaser, B., 2013. Chemical
evaluation of chars produced by
thermochemical conversion
(gasification, pyrolysis and
hydrothermal carbonization) of agro-
industrial biomass on a commercial
scale. Biomass Bioenergy 59, 264–278.
Wiedner, K., Fischer, D., Walther, S., Criscuoli,
I., Favilli, F., Nelle, O., Glaser, B.,
2015. Acceleration of biochar surface
oxidation during composting? J. Agric.
Food Chem. 63 (15), 3830–3837.
Xie, L., Liu, M., Ni, B., Zhang, X., Wang, Y.,
2011. Slow-release nitrogen and boron
fertilizer from a functional
superabsorbent formulation based on
wheat straw and attapulgite. Chem.
Eng. J. 167, 342–348.