2015). They will release the P into the soil solution. Also,
changing the chemical conditions of the soil leads to the P
leaching (Shenker et al. 2004; Zak and Gelbrecht 2007).
Considerable quantity of fertilizers is lost while applying
that leads to environmental problems. Localized applications
of fertilizers (such as salts of ammonia, nitrate, urea, and
phosphate compounds) in large quantity produce harmful
effects (Trenkel 1997; Ombodi and Saigusa 2000). Soils do
not retain nitrates for future utilizations. Also, plants absorb
different nutrients at various times (Smart fertilizer 2020).
Nanomaterials have applications in slow and controlled
release fertilizers that reduce the fertilizer consumption and
environmental pollution as well (Wu and Liu 2008). Slow
and controlled release fertilizers prevent leaching by
releasing the nutrients in a controlled manner.
Engineered nanomaterials can be used in minimum concentration and thereby minimize environmental pollution.
The advantages of nanotechnology lie in crop growth,
enhance the fertilizer use, reduce nutrient losses, and minimize the adverse environmental impacts. The size of the
nanoparticles is in the nanometer level. Hence, they can
enter easily into plant cells since the plant cells are in
micrometer range.
Sulfur nano-coatings applied on fertilizers are beneficial
to the sulfur deficient soils (Santosa et al. 1995; Brady and
Weil 2017). Nanocoated urea and phosphate are prepared to
release the fertilizers in slow or controlled manner. They will
release the nutrients slowly in accordance with the demands
of the soil and crops. Biodegradable and biocompatible
materials such as chitosan nanoparticles (bio-polymer) are
useful in the preparation of controlled release NPK fertilizer
materials, i.e., urea, calcium phosphate, and potassium
chloride (Corradini et al. 2010). Kaolin and polymeric biocompatible nanoparticles are used to prepare slow release
fertilizers (Wilson et al. 2008).
Sabir et al. (2014) have demonstrated that applying
nanocalcite (CaCO 3 -40%) with nano-SiO 2 (4%), MgO (1%),
and Fe 2 O 3 (1%) enhances the uptake of Ca, Mg, and Fe. It
also enhances the intake of the P along with the micronutrients like Zn and Mn (Sabir et al. 2014). Figure 1 exhibits
the different applications related to nanotechnology and
engineered nanomaterials in agriculture such as slow and
controlled released nanofertilizers, nano-based target delivery (nano-carriers), nano-pesticides, and nano-sensors.
These applications enhance the plant growth, productivity,
and yield ultimately (Yilen et al. 2019).
Utilization of engineered nanomaterials (like nanofertilizers, nano-pesticides, and nano-sensors) in agriculture can
increase crop yield by influencing availability of nutrient in
soil and uptake by crops. Engineered nanomaterials can
control the crop diseases by minimizing the pathogens
activities directly (through several mechanisms that includes
releasing of reactive oxygen species). Also, they control
disease indirectly by enhancing crop nutrition and plant
defense mechanisms as well. Efficient use of these materials
may replace conventional fertilizers and pesticides that
ultimately minimize the environmental impact (Adisa et al.
2019).
2 Fertilizers
2.1 Fertilizers in Agriculture
Fertilizers improve the agricultural productivity. However,
the disproportionate utilization of chemical fertilizers causes
damages to soil. Also, it decreases the available area (with
good condition soil) which is necessary for crop production.
Sustainable agriculture suggests reducing the utilization of
agrochemicals. Advancements in nanotechnology (like
enhanced crop productivity) are applied to overcome the
agricultural crisis that leads to sustainability (Priyom Bose
2020).
Some complex fertilizers are harmful to the crops. For
example, to supply potassium to the crop instead of using
potassium chloride as a fertilizer, potassium nitrate (KNO 3 )
can be used. Potassium chloride contains chloride which is
harmful to the crops. On the other hand, KNO 3 contains
more nitrate than ammonium. The uptake of essential
nutrition elements like K, Ca, and Mg is impaired by
ammonium. Hence, KNO 3 is a better option than using
potassium chloride and ammonium (Israelagri.com 2016).
2.2 Classification of Fertilizers
Fertilizers are the chemicals or natural substances to supply
essential nutrients for the plant growth to maintain the soil
fertility. Benton (2012) has reported that fertilizers can be
classified in many approaches: Firstly, fertilizers can be
classified depending upon the contents, i.e., single nutrient
fertilizers or straight fertilizers (e.g., nitrogen—N, phosphorus—P, or potassium—K) and multi-nutrient fertilizers
or complex fertilizers (e.g., two or more nutrients—N and
P); secondly, based on the inorganic and organic content,
i.e., inorganic fertilizers and organic fertilizers. Inorganic
fertilizers do not contain carbon materials. They are prepared
using several chemical treatments. Hence, they are also
called as synthetic fertilizers. All organic fertilizers should
have carbon content and they can be derived from plant
and/or animal sources or recycled materials of plant or
animal source or both (Benton 2012).
Advances of Engineered Nanofertilizers for Modern Agriculture
133
changing the chemical conditions of the soil leads to the P
leaching (Shenker et al. 2004; Zak and Gelbrecht 2007).
Considerable quantity of fertilizers is lost while applying
that leads to environmental problems. Localized applications
of fertilizers (such as salts of ammonia, nitrate, urea, and
phosphate compounds) in large quantity produce harmful
effects (Trenkel 1997; Ombodi and Saigusa 2000). Soils do
not retain nitrates for future utilizations. Also, plants absorb
different nutrients at various times (Smart fertilizer 2020).
Nanomaterials have applications in slow and controlled
release fertilizers that reduce the fertilizer consumption and
environmental pollution as well (Wu and Liu 2008). Slow
and controlled release fertilizers prevent leaching by
releasing the nutrients in a controlled manner.
Engineered nanomaterials can be used in minimum concentration and thereby minimize environmental pollution.
The advantages of nanotechnology lie in crop growth,
enhance the fertilizer use, reduce nutrient losses, and minimize the adverse environmental impacts. The size of the
nanoparticles is in the nanometer level. Hence, they can
enter easily into plant cells since the plant cells are in
micrometer range.
Sulfur nano-coatings applied on fertilizers are beneficial
to the sulfur deficient soils (Santosa et al. 1995; Brady and
Weil 2017). Nanocoated urea and phosphate are prepared to
release the fertilizers in slow or controlled manner. They will
release the nutrients slowly in accordance with the demands
of the soil and crops. Biodegradable and biocompatible
materials such as chitosan nanoparticles (bio-polymer) are
useful in the preparation of controlled release NPK fertilizer
materials, i.e., urea, calcium phosphate, and potassium
chloride (Corradini et al. 2010). Kaolin and polymeric biocompatible nanoparticles are used to prepare slow release
fertilizers (Wilson et al. 2008).
Sabir et al. (2014) have demonstrated that applying
nanocalcite (CaCO 3 -40%) with nano-SiO 2 (4%), MgO (1%),
and Fe 2 O 3 (1%) enhances the uptake of Ca, Mg, and Fe. It
also enhances the intake of the P along with the micronutrients like Zn and Mn (Sabir et al. 2014). Figure 1 exhibits
the different applications related to nanotechnology and
engineered nanomaterials in agriculture such as slow and
controlled released nanofertilizers, nano-based target delivery (nano-carriers), nano-pesticides, and nano-sensors.
These applications enhance the plant growth, productivity,
and yield ultimately (Yilen et al. 2019).
Utilization of engineered nanomaterials (like nanofertilizers, nano-pesticides, and nano-sensors) in agriculture can
increase crop yield by influencing availability of nutrient in
soil and uptake by crops. Engineered nanomaterials can
control the crop diseases by minimizing the pathogens
activities directly (through several mechanisms that includes
releasing of reactive oxygen species). Also, they control
disease indirectly by enhancing crop nutrition and plant
defense mechanisms as well. Efficient use of these materials
may replace conventional fertilizers and pesticides that
ultimately minimize the environmental impact (Adisa et al.
2019).
2 Fertilizers
2.1 Fertilizers in Agriculture
Fertilizers improve the agricultural productivity. However,
the disproportionate utilization of chemical fertilizers causes
damages to soil. Also, it decreases the available area (with
good condition soil) which is necessary for crop production.
Sustainable agriculture suggests reducing the utilization of
agrochemicals. Advancements in nanotechnology (like
enhanced crop productivity) are applied to overcome the
agricultural crisis that leads to sustainability (Priyom Bose
2020).
Some complex fertilizers are harmful to the crops. For
example, to supply potassium to the crop instead of using
potassium chloride as a fertilizer, potassium nitrate (KNO 3 )
can be used. Potassium chloride contains chloride which is
harmful to the crops. On the other hand, KNO 3 contains
more nitrate than ammonium. The uptake of essential
nutrition elements like K, Ca, and Mg is impaired by
ammonium. Hence, KNO 3 is a better option than using
potassium chloride and ammonium (Israelagri.com 2016).
2.2 Classification of Fertilizers
Fertilizers are the chemicals or natural substances to supply
essential nutrients for the plant growth to maintain the soil
fertility. Benton (2012) has reported that fertilizers can be
classified in many approaches: Firstly, fertilizers can be
classified depending upon the contents, i.e., single nutrient
fertilizers or straight fertilizers (e.g., nitrogen—N, phosphorus—P, or potassium—K) and multi-nutrient fertilizers
or complex fertilizers (e.g., two or more nutrients—N and
P); secondly, based on the inorganic and organic content,
i.e., inorganic fertilizers and organic fertilizers. Inorganic
fertilizers do not contain carbon materials. They are prepared
using several chemical treatments. Hence, they are also
called as synthetic fertilizers. All organic fertilizers should
have carbon content and they can be derived from plant
and/or animal sources or recycled materials of plant or
animal source or both (Benton 2012).
Advances of Engineered Nanofertilizers for Modern Agriculture
133