Effects of Biogenic ZnO Nanoparticles on Growth, Physiological, Biochemical Traits and Antioxidants on Olive Tree In Vitro

Abstract

Currently, there is an increasing interest in nanotechnology, since some nanomaterials can enhance crop growth, yield, nutritional status, and antioxidant defences. This work aimed to investigate for the first time the influence of zinc oxide nanoparticles (ZnO-NPs) on the in vitro growth and biochemical parameters of the olive tree (cv. Moraiolo). With this goal, biogenic ZnO-NPs (spherical shape and dimensions in the range of 10–20 nm), deriving from a green synthesis carried out with a Lemna minor L. extract were used. Different concentrations (0, 2, 6 and 18 mg L−1) of ZnO-NPs were added to the olive growth medium (OM substrate), and three sub-cultures of 45 days each were carried out. ZnO-NPs at 6 and 18 mg L−1 enhanced some growth parameters in the olive tree explants, such as the number of shoots, green fresh and total dry weight. Moreover, the abovementioned concentrations raised the chlorophyll a and b content and soluble protein. Finally, concerning the dosage applied, the treatments stimulated the content of carotenoids, anthocyanins, total phenol content (TPC), and the radical scavenging activity towards DPPH (2.2-diphenyl-1-picrylhydrazyl). In conclusion, this study highlighted that biogenic ZnO-NPs exerted beneficial effects on the olive tree explants in vitro, improving the effectiveness of the micropropagation technique.

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

“…Thus, supplying controlled and targeted mineral nutrient release to plants ( Salama et al., 2019 ) and then resulting in increased crop growth and development ( Wang et al., 2018 ; Rajput et al., 2021 ; Srivastava et al., 2021 ). However, recent studies have revealed that NPs may show both positive or negative impact on plants which mainly depends on the chemical structure, size, reactivity, and dose ( Elizabeth et al., 2017 ; Salama et al., 2019 ) that vary according to plant species ( Rastogi et al., 2017 ; Regni et al., 2022 ).…”

“…ZnO NPs application has enhanced plants growth, photosynthesis and development of corn, onion, tomato, olive, capsicum, cucumber, wheat, and zucchini ( Stampoulis et al., 2009 ; Zhao et al., 2013 ; Munir et al., 2018 ; Wang et al., 2018 ; Neto et al., 2020 ; Awan et al., 2021 ; Regni et al., 2022 ) in a dose-dependent manner. Nevertheless, the response of plants to ZnO NPs application is a function of genotypes, the stage of the plant, and the concentration of nanoparticles provided ( Salama et al., 2019 ).…”

ZnO Nanoparticles Obtained by Green Synthesis as an Alternative to Improve the Germination Characteristics of L. esculentum

“…Nevertheless, there is an influence of NPs on emergence. Other authors confirmed the promising effect of ZnO NPs on germination parameters in other types of seeds [ 43 , 44 ].…”

In vitro ZnO Nanoparticles Enhanced Pea (Pisum sativum L.) Seedlings Growth

“…Individually the two concentrations of ZnOs, when tested higher concentrations remarkably increased the shoot length, root length, and leaf numbers (Fig 1,2). The presence of ZnO NPs may have both promote or adverse effects on seed germination, plant development, biochemical and molecular mechanisms depending on dosage or treatment time (Regni et al 2022, Sturikova et al 2018. The results displayed that ZnO NPs supplemented in the development medium at the dosages of 0.8 and 1.8 ppm promoted the length of shoots, the root length, and the number of hairy roots.…”