Foliar Spray of Biosynthesized Zinc Oxide Nanoparticles Alleviate Salinity Stress Effect on Vicia faba Plants

Abstract

Previous studies recorded positive impact of ZnO NPs on plants stressed with salinity. The current work was performed to study the effect of two different concentrations of biosynthesized ZnO NPs (50 and 100 mg L−1) on faba bean plants under salinity stress. The zinc oxide nanoparticles (ZnO NPs) were synthesized using Mentha extract, and their shape and size were characterized using X-ray diffraction and transmission electron microscope while diffuse reflectance spectra were measured using UV–Vis spectrophotometer. The generated ZnO NPs were spherical with a particle size 9.4 nm and had a rod form with particle size 15.2 in length and 3.5 nm in width. The response of faba been plants to the foliar spray of ZnO NPs concentrations (0, 50, and 100 mg L−1) alone and in combination with salt stress at 150 mM NaCl was studied. Salinity induced reduction in faba bean root and shoot length and dry/fresh weights, while an enhancement was recorded in response to foliar treatment with ZnO NPs at 50 and 100 mg L−1 either in presence or absence of salinity stress. The highest amounts of chlorophyll a, b, carotenoids, and total pigments were recorded in plants received 50 mg L−1 ZnO NPs compared to the alternative control. Secondary metabolites (phenols, flavonoids, and tannins) were accumulated in salinity-stressed plants and further accumulation in response to ZnO NPs treatment was noticed. Amino acids, proline, glycine betaine, and total soluble sugars, as well as enzymatic and non-enzymatic antioxidant contents, increased almost onefold in salinity-stressed plants as compared to control plants while the 50 mg L−1 ZnO NPs treatment resulted in higher accumulation of the previously mentioned substances. In contrast, plants oxidative stress was reduced in response to ZnO NPs treatments. The nitrogen, phosphorus, potassium, calcium, zinc, and iron contents of faba bean plants were recorded under salinity stress and in response to the two applied concentrations of ZnO NPs. Faba bean plants stressed with 150 MN NaCl showed growth decline that may be attributed to osmotic stress and low water availability imposed by salinity. The treatment of stressed plants with 50 mg L−1 ZnO NPs induced an enhancement in plant growth as well as an accumulation of antioxidants, osmolytes, and secondary metabolites that could help plants overcome the negative effects of salinity.

Effect of zinc oxide nanoparticles synthesized from Carya illinoinensis leaf extract on growth and antioxidant properties of mustard (Brassica juncea)

“…(2016) have also reported increase in TFC in one of the closely related species of B. juncea , namely B. nigra seedlings treated with ZnO NPs. Comparably, the ZnO NPs treatment was shown to increase the contents of TFC in Glycyrrhiza glabra seedlings ( Oloumi et al., 2015 ), Persicaria hydropiper ( Hussain et al., 2021 ) Raphanus sativus ( Mahmoud et al., 2019 ) and Vicia faba ( Mogazy and Hanafy, 2022 ) plants. The use of nanoparticles as oxidative stress producers resulted in the production of secondary metabolites like flavonoids and phenols that function as ROS scavengers ( Javed et al., 2017 ; Vela´zquez-Gamboa et al., 2021 ; Mogazy and Hanafy, 2022 ).…”

Biosynthesis of TiO2 nanoparticles by Caricaceae (Papaya) shell extracts for antifungal application

“…Attentiveness in titanium dioxide (TiO 2 ), a metallic oxide, has been growing in current times. Titanium dioxide (Titania) is the furthermost hopeful mineral oxide that is broadly being utilized for fabrications of instruments and other applications 3 , 4 . TiO 2 is encouraging for application in the light-emitting device (LCD and LED) that operates in the short wavelength array, from blue light to ultra-violet, as well as in photovoltaic solar cells detectors thin films 5 .…”

Zinc Oxide Nanoparticles Improve Salt Tolerance in Rice Seedlings by Improving Physiological and Biochemical Indices

“…Hezaveh et al [74] recommended a value of 20 mg/L to alleviate the effect of salinity stress on the Brassica napus cultivar at the flowering stage. Recently, Mogazy et al [75] demonstrated that 50 mg/L ZnO-NPs with NaCl could enhance the growth and antioxidant activity in Vicia faba under salinity stress. Similarly, in our study, a low concentration of ZnO-NPs (50 mg/L) was used and did not exert a negative impact on O. sativa genotypes.…”