The long-term use of chemical fertilizers to maintain agricultural production has had various harmful effects on farmland and has greatly impacted agriculture's sustainable expansion. Graphene, a unique and effective nanomaterial, is used in plant-soil applications to improve plant nutrient uptake, reduce chemical fertilizer pollution by relieving inadequate soil nutrient conditions and enhance soil absorption of nutrient components. We investigated the effects of graphene amendment on nutrient content, maize growth, and soil physicochemical parameters. In each treatment, 5 graphene concentration gradients (0, 25, 50, 100, and 150 g kg⁻¹) were applied in 2 different types (single-layer and few-layers, SL and FL). Soil aggregates, soil accessible nutrients, soil enzyme activity, plant nutrients, plant height, stem diameter, dry weight, and fresh weight were all measured throughout the maize growth to the V3 stage. Compared to the control (0 g kg⁻¹), we found that graphene increased the percentage of large agglomerates (0.25–10 mm) in the soil and significantly increased the geometric mean diameter (GMD) and mean weight diameter (MWD) values of > 0.25 mm water-stable agglomerates as the increase of concentration. Soil available nutrient content (AN, AP, and AK) increased, peaking at 150 g kg⁻¹. Graphene boosted nutrient absorption by maize plants, and aboveground total nitrogen (TN), total phosphorus (TP), and total potassium (TK) contents rose with the increasing application, which raised aboveground fresh weight, dry weight, plant height, and stalk thickness. The findings above confirmed our prediction that adding graphene to the soil may improve maize plant biomass by enhancing soil fertility and improving the soil environment. Given the higher manufacturing cost of single-layer graphene and the greater effect of few-layer graphene on soil and maize plants at the same concentration, single-layer graphene and few-layer graphene at a concentration of 50 g kg⁻¹ were the optimal application rates.

Maize seedlings in cold regions and high latitude often face abiotic stress. As a result, weak seedlings affect maize production, The commonly used seed coating agents in production are mainly to prevent biological stress of pests and diseases, and have little effect on seedling vigor and abiotic resistance. In this experiment, the combination of graphene oxide (GO) and seed coating agent can effectively prevent pests and diseases and increase the growth of seedlings.The effects of different concentrations of composite GO seed coating agent on photosynthetic carbon and nitrogen metabolism activity of maize were verified by pot experiments. It provides a reference for the application of nanomaterials in maize seed adjuvant technology and the improvement of maize seedling quality. Using maize as a model plant, the study evaluates, 22 g/L(T1), 44 g/L(T2), 66 g/L(T3), and 88 g/L(T4), GO were add respectively. Commercial seed coating agent as control (Con). Under the conditions of this experiment, GO thickened the stem by regulating the nutrients absorption of the roots in maize seedlings. The leaf thickness and vascular bundle area were increased, the photosynthetic efficiency of leaves were improved. Finally, it promoted the carbon and nitrogen metabolism of maize seedling leaves. Therefore, 44 g/L GO is the most suitable concentration as a coating agent in this experiment.