Zinc Oxide Nanoparticles Induced Oxidative Stress and Changes in the Photosynthetic Apparatus in Fenugreek (Trigonella foenum graecum L.).

The aim of this work was to study the toxicity of nanosheet zinc oxide nanoparticle with the size of 45 nm. The penetration of nanoparticles at an exposure by a localized spray does not make it possible to understand the mechanism of transport and bioavailability of the nanoparticles. In contrast, nanoparticles penetrated, via the roots, as a function of their diameter, the smaller ones having caused leaf stress (by translocation) at low concentrations. So that the choice of method of root application. Plants treated with 50 mg L-1 of ZnO-NPs presented disturbance in leaf due to changes in chlorophyll's biosynthesis. The highest value of the photosynthetic pigments was recorded at 5 mg L-1 of ZnO-NPs. However, the treatment with 50 mg L-1 of ZnO-NPs caused a decrease in the levels of chlorophyll a and b. Moreover, ZnO-NPs leaves significantly enhanced antioxidant enzymes activities.