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

Abstract

Tomato is an important crop due to its nutritional contributions and organoleptic properties, which make it an appetizing vegetable around the world. In its sowing, the use of seed is the most accessible propagation mechanism for farmers. However, the induction to germination and emergence is often limited in the absence of stimulants that promote the development and growth of the seedling, added to the interference of infectious agents that notoriously reduce the vitality and viability of the seed. Given this, it was proposed as a research objective to determine the effect of zinc oxide nanoparticles (ZnO NPs) mediated by a green route on the germinative characteristics of Lycopersicon esculentum Mill. 1768 “tomato”. The experimental phase consisted of the synthesis of ZnO NPs and its subsequent characterization. After its synthesis, its inoculation was conducted during the germination of seeds of L. esculentum, considering six sample groups for the treatment with zinc nanoparticles (T1: Control; T2: 21.31 ppm; T3: 33.58 ppm; T4: 49.15 ppm; T5: 63.59 and T6: 99.076 ppm). The results indicate that concentrations close to 100 ppm of ZnO NPs are ideal in the treatment of L. esculentum seeds, due to the promotion of enzymatic and metabolic activity to achieve cell elongation; likewise, the biosynthesized nanoparticles showed no phytotoxicity, due to the fact that, in all the treatments, there were processes of germination and emergence. This was linked to the generation of a Zn0-phenolate complex through a chelating effect, which generates compatibility with the seed and, compared to classic inorganic synthesis, usually shows phytotoxicity. In this sense, green synthesis is presented as a great alternative in this type of application.

Development and Evaluation of Zinc and Iron Nanoparticles Functionalized with Plant Growth-Promoting Rhizobacteria (PGPR) and Microalgae for Their Application as Bio-Nanofertilizers

“…Singh et al [32] indicated that green ZnO-NPs (35 nm) applied at 62 ppm showed the most significant improvement in wheat seed germination and seedling growth relative to other concentration levels. Asmat-Campos et al [33] also revealed that concentrations of ZnO-NPs (30 nm) close to 100 ppm (63.59 and 99.076 ppm) are the best to enhance tomato seeds germination since they promote metabolic activity to induce cell elongation, no phytotoxicity was observed. Itrouthwar et al [34] also evaluated ZnO-NPs (37 nm) in maize; they found that the concentration of 100 ppm exhibited the highest seed germination rate and seedling growth parameters as compared with zinc acetate (ionic control) and water (normal control).…”

Wheat Performance Affected by Green-Synthesized T-ZnO-NPs: A Comprehensive Study on Soil, Foliar, and Hydrogel Applications

“…6d). The maximum Zn 2+ uptake was determined at the 2000 mg/L as 20.32 mg/g dw (p < 0.05), while the control plants had 13.26 mg Zn 2+ /g dw. In other words, plants did not uptake the Zn 2+ in the environment when T-ZnO-NPs suspension were present at concentrations as high as 5000 mg/L (13.72 mg Zn/g DW) in the environment.…”

Impact of Biologically and Chemically Synthesized Zinc Oxide Nanoparticles on Seed Germination and Seedlings’ Growth

“…Recent studies show that the use of ZnONPs obtained via green synthesis at concentrations of 10-100 mg L −1 improved seed germination, the size of roots, shoots, and leaves, the number of roots, and the total fresh biomass in various plants: Triticum aestivum [24], Phaseolus vulgaris, Vigna angularis [25], and Hordeum vulgare [26]. In addition, ZnONPs obtained via green synthesis do not generate toxicity in concentrations of up to 100 mg L −1 in tomato seeds [27]. Sharma et al established that the concentration of ZnONPs at 20 mg L −1 improved the germination rate, the vigor of the seedlings, the production of reactive oxygen species (ROS), and the metabolic process of starch [28].…”