reported an rising trend (but statistically insignificant) in total chlorophyll content in cucumber (Cucumis sativus) treated with 400 and 800 mg/kg bare-ZnO NP in soil (Zhao et al., 2013b). Zinc is an critical micronutrient in plants (Hansch and Mendel, 2009) but above a “threshold” concentration, the element can generate toxicity in distinct plant species (Broadley et al., 2007; Zhao et al., 2013b). For instance, Kupper et al. (1996) reported that zinc can substitute the central metal atom magnesium (Mg2+ ) in chlorophyll, causing a breakdown of the photosynthetic approach. It has been reported that above 200 mg/kg (threshold worth) in leaf tissues, Bacopa monniera and Lolium perenne L. cv Apollo showed phytotoxicological responses (Ali et al., 2000; Bonnet, 2000). In our study, the maximum Zn concentration in leaf was <300 mg/kg DW. This value is likely less than the threshold Zn tolerance value (not determined here) for green pea leavesFrontiers in Plant Science | http://www.frontiersin.orgJanuary 2016 | Volume 6 | ArticleMukherjee et al.Nanoparticle Doping Impacts Phytotoxicityunder our particular growth condition. Moreover, at 1000 mg/kg, carotenoid concentrations increased up to 9 fold, compared to control. Carotenoids are photo-absorbing pigments which might have protected Chl-a from photooxidation (Lichtenthaler, 1987). In leaf tissues, the unchanged (Chl-b) or increased (Chla, carotenoids) pigment content clearly suggests little or no toxicity to photosynthetic pigment production with Zn exposure. However, these findings may not exclude the possibility of damage to other components of the photosynthetic apparatus, e.g., electron transport chains and photosynthetic enzyme activities. Further biochemical investigations are warranted to evaluate the effects of ZnO NP exposure on other complex photosynthetic components.Effects of NPs on Green Pea Seed QualityExposure to Zn, regardless of type, generally had little effect on the green pea pod characteristics. The pod length, pod weight, and number of seeds per pod did not change as a function of treatment, with the exception of doped 250 mg/kg nanoparticles (data not shown). Here, the number of seeds per pod decreasedby 33 compared to that of bare ZnO NP treatment. Unlike bulk treatments, bare, fpsyg.2014.00726 doped, and coated NPs showed increase in Zn uptake at 250 mg/kg therapy, in comparison with handle (Figure six). At 1000 mg/kg, the Zn content material improved by two?.5 times in all NP and bulk therapies as when compared with control. The ionic treatments didn’t show any significant modify in Zn uptake at five mg/kg or 20 mg/kg. Concentrations of Cu, Mg, and K within the seed didn’t transform significantly with Zn exposure (information not shown). The Fe level was substantially elevated by the coated (250 mg/kg) and doped (1000 mg/kg) treatment options. Also, at 1000 mg/ kg coated remedy, P and Mn had been substantially increased (Figures 6B ). General, Zn exposure, irrespective of variety or concentration, had small impact on the protein or carbohydrate profile from the green pea seeds. The quantity of acid-soluble (glutelin), salt-soluble (globulin), water-soluble (Daprodustat web albumin), and alcoholsoluble (prolamin) protein fractions remained unaltered in dar.12324 all remedies (Figure S6). There was a decrease in glutelin quantity (50 ) at 1000 mg/kg doped treatment, in comparison with handle, but as a consequence of big variability and modest replica.