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Deleterious Effects of NPs on the Genetic Constitution
of Plants: Genotoxicity
Exposure of Ag NPs induced alteration in cell division and genotoxicity to Allium
cepa roots (Kumari et al. 2009). Likewise, magnetic NP exposure has also been
documented to influence the root cell growth and development of maize plants
(Racuciu and Creanga 2009a). Exposure of SWCNTs was found to induce programmed cell death in A. thaliana and rice plants (Shen et al. 2010). A. thaliana
plants showed disrupted root growth on TiO 2 NP exposure (Wang et al. 2011). TiO 2
NPs were also observed to negatively affect the seed germination and root elongation of Vicia narbonensis and maize plants (Castiglione et al. 2011). TiO 2 NPs also
inhibited the germination and growth of Vicia narbonensis (Castiglione et al. 2014).
Ag NPs have also been reported to lower the reproduction efficiency of kiwi plants
(Speranza et al. 2013). So, NPs have the potential to disturb the genetic makeup of
plants, which ultimately affect their growth, development, and physiology. Further,
being genetic defects, these ill effects of NP exposure can be transferred to coming
generations.
Negative Effect of NPs on Plant Nutritional Quality/Status
Exposure of CeO 2 NPs was found to reduce the nutritional quality of rice seedlings.
The seedlings showed reduction in iron, sulfur, prolamine, glutelin, lauric acid,
valeric acid, and starch content. Further, the antioxidant content of seedlings was
also reduced. Thus, CeO 2 exposure has a deteriorating effect on the nutritional value
of rice (Rico et al. 2013b). CeO 2 NPs also reduced the fresh weight of fruits in
cucumber plants (Zhao et al. 2014). Similarly, ZnO NPs decreased the iron content
and increased the zinc accumulation of soybean plants. However, CeO 2 exposure
decreased the uptake of elements involved in photosynthesis and nitrogen metabolism of soybean (Peralta-Videa et al. 2014). Ag NPs were reported to induce mild
stress on aquatic plant, Bacopa monnieri (Krishnaraj et al. 2012). Ag NPs and FeO
NPs were observed to disturb the nutrient uptake and the growth of the mycorrhizal
clover (Trifolium repens) plant. The lower dose of Ag NPs induced more toxicity
than a higher tested dose. In contrast, a higher dose of FeO NPs induced more plant
growth inhibition than a lower dose (Feng et al. 2013). MWCNTs also induced
nutrient imbalance and damage to leaves in Vicia faba (Wang et al. 2014).
10.3 Mechanism Regulating Plant–NP Interactions
Exposure of different type of NPs can variously affect plant growth and development. The NPs of even the same chemical composition can positively as well as
negatively affect the plants depending upon their size, shape, surface covering, concentration, and mode of NP exposure. Hence, it becomes essential to investigate the
mechanism of NP interaction with plants.
V. Kumar et al.
Deleterious Effects of NPs on the Genetic Constitution
of Plants: Genotoxicity
Exposure of Ag NPs induced alteration in cell division and genotoxicity to Allium
cepa roots (Kumari et al. 2009). Likewise, magnetic NP exposure has also been
documented to influence the root cell growth and development of maize plants
(Racuciu and Creanga 2009a). Exposure of SWCNTs was found to induce programmed cell death in A. thaliana and rice plants (Shen et al. 2010). A. thaliana
plants showed disrupted root growth on TiO 2 NP exposure (Wang et al. 2011). TiO 2
NPs were also observed to negatively affect the seed germination and root elongation of Vicia narbonensis and maize plants (Castiglione et al. 2011). TiO 2 NPs also
inhibited the germination and growth of Vicia narbonensis (Castiglione et al. 2014).
Ag NPs have also been reported to lower the reproduction efficiency of kiwi plants
(Speranza et al. 2013). So, NPs have the potential to disturb the genetic makeup of
plants, which ultimately affect their growth, development, and physiology. Further,
being genetic defects, these ill effects of NP exposure can be transferred to coming
generations.
Negative Effect of NPs on Plant Nutritional Quality/Status
Exposure of CeO 2 NPs was found to reduce the nutritional quality of rice seedlings.
The seedlings showed reduction in iron, sulfur, prolamine, glutelin, lauric acid,
valeric acid, and starch content. Further, the antioxidant content of seedlings was
also reduced. Thus, CeO 2 exposure has a deteriorating effect on the nutritional value
of rice (Rico et al. 2013b). CeO 2 NPs also reduced the fresh weight of fruits in
cucumber plants (Zhao et al. 2014). Similarly, ZnO NPs decreased the iron content
and increased the zinc accumulation of soybean plants. However, CeO 2 exposure
decreased the uptake of elements involved in photosynthesis and nitrogen metabolism of soybean (Peralta-Videa et al. 2014). Ag NPs were reported to induce mild
stress on aquatic plant, Bacopa monnieri (Krishnaraj et al. 2012). Ag NPs and FeO
NPs were observed to disturb the nutrient uptake and the growth of the mycorrhizal
clover (Trifolium repens) plant. The lower dose of Ag NPs induced more toxicity
than a higher tested dose. In contrast, a higher dose of FeO NPs induced more plant
growth inhibition than a lower dose (Feng et al. 2013). MWCNTs also induced
nutrient imbalance and damage to leaves in Vicia faba (Wang et al. 2014).
10.3 Mechanism Regulating Plant–NP Interactions
Exposure of different type of NPs can variously affect plant growth and development. The NPs of even the same chemical composition can positively as well as
negatively affect the plants depending upon their size, shape, surface covering, concentration, and mode of NP exposure. Hence, it becomes essential to investigate the
mechanism of NP interaction with plants.
V. Kumar et al.