2.4 Major Elements of Plants
Plants are created by the composition of four main elements,
i.e., carbon, hydrogen, oxygen, and nitrogen. Apart from the
life of plants, they have major roles in the creation of entire
biological system (including human, animals, and microorganisms) and maintenance of life. These elements present in
carbohydrate, protein, and fat that are utilized as food/feed
by human and animals. Phosphate is essential for the DNA,
ATP (energy carrier of cells), some lipids, and bones of
human and animals.
Plants can get hydrogen and oxygen from water and
carbon from carbon dioxide. Nitrogen is present in the
atmosphere. However, plants are unable to use it. Plants
require it in a fixed form because of its major role in the
development of proteins, DNA, and other important components like chlorophyll. Some bacteria and legumes fix
atmospheric nitrogen (N 2 ) by ammonia conversion. Phosphate plays a major role in the DNA, ATP, and some lipids
production of the plants (Wiki/Fertilizer 2018). Figure 2
depicts that plants utilize carbon dioxide and water (getting
carbon, hydrogen, and oxygen) during photosynthesis to
produce starch and sugar or glucose.
The deficiency of micronutrients reduces the crops productivity that ultimately affects the human health (while
consuming the low nutrient foods). For example, iron deficiency causes anemia and affecting growth, reproductive
health, and cognitive performance in humans (Swaminathan
et al. 2013; Monreal et al. 2016). Hence, imbalance (surplus
supply or deficiency) of the main elements, macronutrients,
and micronutrients in plants will affect the living things of
entire biological system including plants. It emphasizes the
significance of the fertilizers.
3 Engineered Nanofertilizers
3.1 Technology of Nanofertilizers
Nanotechnology develops agricultural products such as
nanofertilizers,
nano-herbicides,
nano-pesticides,
nano-fungicides, and nano-sensors (Duhan et al. 2017).
Also, nanotechnology supports for agriculture by making
nanoscale carriers, bio-remediation of pesticides, wastewater
treatment, enzymatic sensors, nano-lingocellulose, and clay
nanotubes (Dasgupta et al. 2015). Many countries are
applying nanotechnology in agriculture and food sectors. It
will support to meet the demands and to feed of the
increased population (Ali et al. 2014).
Nanofertilizers are defined as the synthesized or modified
form of traditional fertilizers or fertilizers bulk materials or
extracted from different vegetative or reproductive parts of
the plant by different chemical, physical, mechanical, or
biological methods with the help of nanotechnology used to
improve soil fertility, productivity, and quality of agricultural produces. Nanoparticles can be made from fully bulk
materials (Brunnert et al. 2006).
3.2 Classification of Nanofertilizers
Different classifications and types of nanofertilizers are
shown in Fig. 3. Classifications of nanofertilizers, i.e.,
nutrient-based, action-based, and based on the quantity
applied are shown in Fig. 3a–c, respectively. Like conventional fertilizers (as explained earlier), nanofertilizers also
have macro and micronutrients. However, in the case of
nanofertilizers, the size of the nutrients (it may be
macronutrients or micronutrients) is in nanoscale range.
Ruiqiang and Rattan (2016) reported about the
nutrient-based classification of nanofertilizers. Figure 3a
shows this classification of nanofertilizers based on nutrients. Nanofertilizers supply nutrients to the plants that
improve the plant growth and yields. Also, they are applied
to enhance the performance of conventional fertilizers. They
are divided into four classes: macronutrient nanofertilizers
(e.g., apatite nanoparticles), micronutrient nanofertilizers
(e.g., iron oxide NPs and zinc oxide NPs), nutrient-loaded
nanofertilizers (e.g., zeolites), and plant growth stimulating
nanomaterials (e.g., carbon nanomaterials). Developing the
macronutrient nanofertilizers (nitrogen and phosphorus) is
necessary to improve agricultural activities and to reduce
environmental problems (Ruiqiang and Rattan 2016).
Based on the actions, nanofertilizers are categorized as
control or slow release fertilizers, water, and nutrient loss
control fertilizers (WNLCF), magnetic, or nanocomposite
fertilizers combined nanodevices (Lateef et al. 2016; Panpatte et al. 2016). This classification is shown in Fig. 3b.
Priyom Bose (2020) has divided the nanofertilizers (based
on the quantity applied) into three types: (i) nanoscale fertilizers: these are nano-sized particles that have nutrients,
(ii) nanoscale coating fertilizers: nanoparticles coated or
loaded on traditional fertilizers, and (iii) nanoscale additive
fertilizers: these fertilizers are the traditional fertilizers mixed
with the nano-sized additives (Priyom Bose 2020). Figure 3c
shows the classification based on the quantity applied.
Nanofertilizers combined nanodevices are designed with
a nanonetwork to monitor the plants. The monitoring system
comprises of nano and microscale network devices. These
devices and the data collected by them are managed by
control units. The transmitters (nano-sensors) collect data
and transmit to receivers (micro-devices). Finally, the
data are relayed to the Internet through gateways (Dufresne
2000; Luca 2018). Attapulgite or Palygorskite clay is one
of the varieties of fuller's earth clay material. Magnesium
aluminum phyllosilicate is the chemical content and
Advances of Engineered Nanofertilizers for Modern Agriculture
135
Plants are created by the composition of four main elements,
i.e., carbon, hydrogen, oxygen, and nitrogen. Apart from the
life of plants, they have major roles in the creation of entire
biological system (including human, animals, and microorganisms) and maintenance of life. These elements present in
carbohydrate, protein, and fat that are utilized as food/feed
by human and animals. Phosphate is essential for the DNA,
ATP (energy carrier of cells), some lipids, and bones of
human and animals.
Plants can get hydrogen and oxygen from water and
carbon from carbon dioxide. Nitrogen is present in the
atmosphere. However, plants are unable to use it. Plants
require it in a fixed form because of its major role in the
development of proteins, DNA, and other important components like chlorophyll. Some bacteria and legumes fix
atmospheric nitrogen (N 2 ) by ammonia conversion. Phosphate plays a major role in the DNA, ATP, and some lipids
production of the plants (Wiki/Fertilizer 2018). Figure 2
depicts that plants utilize carbon dioxide and water (getting
carbon, hydrogen, and oxygen) during photosynthesis to
produce starch and sugar or glucose.
The deficiency of micronutrients reduces the crops productivity that ultimately affects the human health (while
consuming the low nutrient foods). For example, iron deficiency causes anemia and affecting growth, reproductive
health, and cognitive performance in humans (Swaminathan
et al. 2013; Monreal et al. 2016). Hence, imbalance (surplus
supply or deficiency) of the main elements, macronutrients,
and micronutrients in plants will affect the living things of
entire biological system including plants. It emphasizes the
significance of the fertilizers.
3 Engineered Nanofertilizers
3.1 Technology of Nanofertilizers
Nanotechnology develops agricultural products such as
nanofertilizers,
nano-herbicides,
nano-pesticides,
nano-fungicides, and nano-sensors (Duhan et al. 2017).
Also, nanotechnology supports for agriculture by making
nanoscale carriers, bio-remediation of pesticides, wastewater
treatment, enzymatic sensors, nano-lingocellulose, and clay
nanotubes (Dasgupta et al. 2015). Many countries are
applying nanotechnology in agriculture and food sectors. It
will support to meet the demands and to feed of the
increased population (Ali et al. 2014).
Nanofertilizers are defined as the synthesized or modified
form of traditional fertilizers or fertilizers bulk materials or
extracted from different vegetative or reproductive parts of
the plant by different chemical, physical, mechanical, or
biological methods with the help of nanotechnology used to
improve soil fertility, productivity, and quality of agricultural produces. Nanoparticles can be made from fully bulk
materials (Brunnert et al. 2006).
3.2 Classification of Nanofertilizers
Different classifications and types of nanofertilizers are
shown in Fig. 3. Classifications of nanofertilizers, i.e.,
nutrient-based, action-based, and based on the quantity
applied are shown in Fig. 3a–c, respectively. Like conventional fertilizers (as explained earlier), nanofertilizers also
have macro and micronutrients. However, in the case of
nanofertilizers, the size of the nutrients (it may be
macronutrients or micronutrients) is in nanoscale range.
Ruiqiang and Rattan (2016) reported about the
nutrient-based classification of nanofertilizers. Figure 3a
shows this classification of nanofertilizers based on nutrients. Nanofertilizers supply nutrients to the plants that
improve the plant growth and yields. Also, they are applied
to enhance the performance of conventional fertilizers. They
are divided into four classes: macronutrient nanofertilizers
(e.g., apatite nanoparticles), micronutrient nanofertilizers
(e.g., iron oxide NPs and zinc oxide NPs), nutrient-loaded
nanofertilizers (e.g., zeolites), and plant growth stimulating
nanomaterials (e.g., carbon nanomaterials). Developing the
macronutrient nanofertilizers (nitrogen and phosphorus) is
necessary to improve agricultural activities and to reduce
environmental problems (Ruiqiang and Rattan 2016).
Based on the actions, nanofertilizers are categorized as
control or slow release fertilizers, water, and nutrient loss
control fertilizers (WNLCF), magnetic, or nanocomposite
fertilizers combined nanodevices (Lateef et al. 2016; Panpatte et al. 2016). This classification is shown in Fig. 3b.
Priyom Bose (2020) has divided the nanofertilizers (based
on the quantity applied) into three types: (i) nanoscale fertilizers: these are nano-sized particles that have nutrients,
(ii) nanoscale coating fertilizers: nanoparticles coated or
loaded on traditional fertilizers, and (iii) nanoscale additive
fertilizers: these fertilizers are the traditional fertilizers mixed
with the nano-sized additives (Priyom Bose 2020). Figure 3c
shows the classification based on the quantity applied.
Nanofertilizers combined nanodevices are designed with
a nanonetwork to monitor the plants. The monitoring system
comprises of nano and microscale network devices. These
devices and the data collected by them are managed by
control units. The transmitters (nano-sensors) collect data
and transmit to receivers (micro-devices). Finally, the
data are relayed to the Internet through gateways (Dufresne
2000; Luca 2018). Attapulgite or Palygorskite clay is one
of the varieties of fuller's earth clay material. Magnesium
aluminum phyllosilicate is the chemical content and
Advances of Engineered Nanofertilizers for Modern Agriculture
135