oleracea) (Zhang et al. 2005). Zhang et al. (2005) and Hong et al. (2005) reported
that nanosized TiO 2 could promote photosynthesis and nitrogen metabolism and
consequently improve the growth of spinach at a suitable concentration. But Yang
and Watts (2005) concluded that treatment with uncoated alumina nanoparticle
inhibit root elongation of cucumber (Cucumis sativus), corn (Zea mays), cabbage
(Brassica oleracea), soybean (G. max), and carrot (Daucus carota). Zhang et al.
(2005) reported that nanosized TiO 2 treatment at 250–4000 ppm, in comparison with
bulk TiO 2 , improved the germination rate and the germination and vigor indexes of
spinach. Gao et al. (2006) revealed that nano-anatase TiO 2 accelerated Rubisco
carboxylase activity by 2.67 times in S. oleracea. Lee et al. (2008) concluded that
the growth rates of Phaseolus radiatus and Triticum aestivum plants were retarded
when exposed to nanoparticles and there was a negative correlation between seedling length and the concentration of nanoparticles. It is clear from different studies
that nanoparticles can influence the germination, growth, and yield of different
crops. In several experiments (Maity et al. 2016), NPs enhanced germination
significantly, but at higher doses, in some cases, it reduced the germination. Regarding yield data at field level, scanty of literatures (Maity et al. 2016, 2018; Srinivasan
et al. 2017) have still been produced. Prasad et al. (2012) suggested that the
micronutrients like Zn content of seed could be enriched after treating seed with
nanoscale ZnO that eventually improves the germination, shoot–root growth, dry
weight, and pod yield. In our study, ZnO NPs enhanced seed yield at lower doses
whereas decreased it at higher doses, but NPs overtook the control at all doses.
Roghayyeh et al. (2010) have also reported that treatment with nano-iron could
increase in leaf and pod weight and finally the seed yield of soybean, whereas the
growth of Sesbania was unaffected by treatment with nano-gold even up to 200 ppm.
Musante and White (2010) have reported a reduction in growth of Cucurbita pepo,
on treatment with silver and copper nanoparticles, whereas Miao et al. (2007) have
reported the same trend with silver nanoparticles on phytoplankton growth. Still,
limited information is available on the exact mode of action of the nanoparticles on
crop plants. Metal nanoparticles provide additional surface area for electron
exchange with biomolecules (Shah and Belozerova 2009), and thus, antioxidant
status of the treated living materials can be altered by nanoparticles, by virtue of their
innate role in cellular redox reactions.
9.2.3 Crop Protection
To meet the food demand of growing population, there is excessive use of pesticide
worldwide to combat pests and pathogens. Alternative way of restricting use of
pesticide is the need of the hour. Very less amount of pesticides (nearly 0.1%)
reaches to the target sites, and the rest are lost to the environment by runoff, spray
drift, off-target deposition, and photodegradation, thus increasing environmental
and application costs (Castro et al. 2013). Among the latest progress in agricultural
sciences, nanomaterials play a very important role in plant protection since it has
9 Application of Nanotechnology in Agriculture
331
that nanosized TiO 2 could promote photosynthesis and nitrogen metabolism and
consequently improve the growth of spinach at a suitable concentration. But Yang
and Watts (2005) concluded that treatment with uncoated alumina nanoparticle
inhibit root elongation of cucumber (Cucumis sativus), corn (Zea mays), cabbage
(Brassica oleracea), soybean (G. max), and carrot (Daucus carota). Zhang et al.
(2005) reported that nanosized TiO 2 treatment at 250–4000 ppm, in comparison with
bulk TiO 2 , improved the germination rate and the germination and vigor indexes of
spinach. Gao et al. (2006) revealed that nano-anatase TiO 2 accelerated Rubisco
carboxylase activity by 2.67 times in S. oleracea. Lee et al. (2008) concluded that
the growth rates of Phaseolus radiatus and Triticum aestivum plants were retarded
when exposed to nanoparticles and there was a negative correlation between seedling length and the concentration of nanoparticles. It is clear from different studies
that nanoparticles can influence the germination, growth, and yield of different
crops. In several experiments (Maity et al. 2016), NPs enhanced germination
significantly, but at higher doses, in some cases, it reduced the germination. Regarding yield data at field level, scanty of literatures (Maity et al. 2016, 2018; Srinivasan
et al. 2017) have still been produced. Prasad et al. (2012) suggested that the
micronutrients like Zn content of seed could be enriched after treating seed with
nanoscale ZnO that eventually improves the germination, shoot–root growth, dry
weight, and pod yield. In our study, ZnO NPs enhanced seed yield at lower doses
whereas decreased it at higher doses, but NPs overtook the control at all doses.
Roghayyeh et al. (2010) have also reported that treatment with nano-iron could
increase in leaf and pod weight and finally the seed yield of soybean, whereas the
growth of Sesbania was unaffected by treatment with nano-gold even up to 200 ppm.
Musante and White (2010) have reported a reduction in growth of Cucurbita pepo,
on treatment with silver and copper nanoparticles, whereas Miao et al. (2007) have
reported the same trend with silver nanoparticles on phytoplankton growth. Still,
limited information is available on the exact mode of action of the nanoparticles on
crop plants. Metal nanoparticles provide additional surface area for electron
exchange with biomolecules (Shah and Belozerova 2009), and thus, antioxidant
status of the treated living materials can be altered by nanoparticles, by virtue of their
innate role in cellular redox reactions.
9.2.3 Crop Protection
To meet the food demand of growing population, there is excessive use of pesticide
worldwide to combat pests and pathogens. Alternative way of restricting use of
pesticide is the need of the hour. Very less amount of pesticides (nearly 0.1%)
reaches to the target sites, and the rest are lost to the environment by runoff, spray
drift, off-target deposition, and photodegradation, thus increasing environmental
and application costs (Castro et al. 2013). Among the latest progress in agricultural
sciences, nanomaterials play a very important role in plant protection since it has
9 Application of Nanotechnology in Agriculture
331