Impact of Foliar Application of ZnO and Fe3O4 Nanoparticles on Seed Yield and Physio-Biochemical Parameters of Cucumber (Cucumis sativus L.) Seed under Open Field and Protected Environment vis a vis during Seed Germination

Abstract

Nutritionally rich cucumber seeds remain in demand in the agricultural, health and cosmetic sectors as they are essential for a successful crop stand establishment and seed-based products. However, the production of cucumber seeds is impeded by source limitation and nutrient deficiency. The foliar application of micronutrients can supplement this deficiency and overcome the physiological setback. An experiment was undertaken to compare the impacts of the foliar application of Fe and Zn, as nanoparticles and fertilizers, on the yield and seed quality of cucumber under open and protected environments. A foliar spray of nano-ZnO (ZnNPs) and nano-Fe3O4 (FeNPs) at 100, 200 and 300 mg L−1, as well as ZnSO4 and FeSO4 as fertilizer (0.5%), was conducted at the vegetative stage and pre- and post-flowering stages. The NPs had a greater efficacy in an open field than in the protected (naturally ventilated poly house) environment. The application of both NPs increased seed yield (51.7–52.2%), total chlorophyll content (15.9–17.3%) and concentration of Zn and Fe in the fruit and the seed, by 2.0–58.5% and 5.0–30.5%, respectively. A significant increase in starch, soluble proteins, soluble sugars and oil content was observed in the seeds from the NP treated plants. NP treatment also enhanced the germination-related parameters, such as percent germination (16.8–17.0%), rate of germination (18.0–22.2%) and seedling vigor (59.8–72.6%). The biochemical characterization showed a significant improvement in the seed water uptake and the activity of hydrolytic enzymes (amylase and protease) in the germinating seed. The involvement of reactive oxygen species (superoxide anion and hydrogen peroxide) and antioxidant enzymes (Superoxide dismutase, Catalase and Peroxidase) in the germination process was indicated by an increase in their activities in the seeds from NP treated plants. Hence, the study proposes the potential benefit of the foliar application of 300 mg L−1 ZnNPs and 200 mg L−1 FeNPs at crucial stages of plant growth to improve the yield and seed quality in cucumbers.

Cloning and Function Analysis of the CsTAU1 in Response to Salt–Alkali Stress

“…This indicates that CsTAU1 has a certain impact on CAT content and improving cucumber's resistance to salt-alkali stress by reducing H 2 O 2 to H 2 O. This result is similar to the research results of Nakul and Pal [39,40].…”

Green synthesis of nano iron oxide using Emblica officinalis L. fruit extract and its impact on growth, chlorophyll content, and metabolic activity of Solanum lycopersicum L.

“…Gupta et al stated that increased antioxidant enzyme activity leads to homeostatic control of ROS levels in cells which in turn determines the state of the seeds during germination, dormancy, and senescence. They observed that foliar application of ZnO NPs and Fe 3 O 4 NPs in the range of 100-300 mg/L in an open field tends to improve physiobiochemical parameters and antioxidant enzyme activity (SOD, CAT, and POD) of Cucumis sativus L; however, above the optimum concentration of 300 mg/L, it showed a deleterious effect [64]. Treatment of Triticum aestivum plants with Fe 3 O 4 NPs (40-500 mg/L) showed prominent increase of Fe, P, and K content in its leaves with enhanced photosynthetic, respiration, and antioxidant enzyme activity (SOD, APX) thereby promoting the growth of plant [59].…”

Germination and Vigor of Soybean and Corn Seeds Treated with Mixed Mineral Fertilizers

“…Seed treatment is the application of fungicides, insecticides, inoculants, stimulants, biological products, or nutrients that preserve or improve seed performance, allowing crops to express their full genetic potential. It is a consolidated technique for cultivating crops, mainly soybean and corn, and avoiding possible losses resulting from the action of soil and shoot pests and the malformation of vegetative structures caused by a lack of nutrients in the early stages [ 2 , 3 , 4 , 5 , 6 , 7 ].…”