Effect of ZnO, SiO2 and composite nanoparticles on Arabidopsis thaliana and involvement of ethylene and cytokinin signaling pathways

Strategies for Enhancing Plant Immunity and Resilience Using Nanomaterials for Sustainable Agriculture

“…67 Interestingly, SiO 2 nanoparticles promoted the plants' growth and chlorophyll contents at all concentrations, induced only a mild upregulation of ET-related genes, and reduced ZnO nanoparticles' toxicity when used in combination. 66 Thus, downregulation or moderate ET stimulation by Ag and SiO 2 nanoparticles seems to be associated with positive outcomes in plant health, which could be helpful under stresses such as flooding or waterlogging. 49 SA-induced defense responses have the potential to be effective against insects such as aphids 68 and thrips.…”

“…For ZnO nanoparticles, reduced growth of Arabidopsis went along with upregulated ET-related genes, which can be explained by Zn 2+ toxicity, given the test concentrations >10 mg L –1 , and the high solubility of ZnO nanoparticles . Interestingly, SiO 2 nanoparticles promoted the plants’ growth and chlorophyll contents at all concentrations, induced only a mild upregulation of ET-related genes, and reduced ZnO nanoparticles’ toxicity when used in combination . Thus, downregulation or moderate ET stimulation by Ag and SiO 2 nanoparticles seems to be associated with positive outcomes in plant health, which could be helpful under stresses such as flooding or waterlogging …”

“…Similar observations were made for CuO and Ag particles . However, higher ZnO nanoparticle concentrations were consistently toxic for the plant. , Overall, these findings show the potential for using different nanomaterials at low concentrations to stimulate plant hormones against pests. With proper size tuning, they might also penetrate plant membranes for targeted applications .…”

“…Ag, SiO 2 , and ZnO nanoparticles modulate plant defenses mediated by ET. , For Ag nanoparticles, a downregulation of aminocyclopropane-1-carboxylic acid synthase (ACC synthase, ACS), a key enzyme in ethylene biosynthesis, went along with increased plant health in Tecomella undulata (a desert tree) in vitro cultures . For ZnO nanoparticles, reduced growth of Arabidopsis went along with upregulated ET-related genes, which can be explained by Zn 2+ toxicity, given the test concentrations >10 mg L –1 , and the high solubility of ZnO nanoparticles . Interestingly, SiO 2 nanoparticles promoted the plants’ growth and chlorophyll contents at all concentrations, induced only a mild upregulation of ET-related genes, and reduced ZnO nanoparticles’ toxicity when used in combination .…”

Nanotechnological approaches for management of soil-borne plant pathogens

“…Additionally, increased levels of organic acids (such as malic, citric, and succinic acids) and sugars (such as glucose, fructose, and sucrose) in the fruits of strawberry plants treated with Se-NPs under saline conditions demonstrated the benefits of Se-NPs on the improvement of fruit quality and nutritional values. Azhar et al (2021) examined phytohormone signaling when different metallic nanoparticles (ZnO, SiO2, and ZnO/SiO2 composite NPs) were exposed to Arabidopsis. They discovered that nanoparticle accumulation in plant tissue altered the expression level of genes associated with the cytokinin signalling pathway (ARR7 and ARR15), which suggested the significance of cytokinin in the plant's response to nanoparticles.…”