Organic Waste Mitigates the Negative Impacts Linked to Nutritional Starvation, Improving Soil Bioindicators, Defense System and Photosynthesis in Maize Plants

Sustainable agricultural technologies are essential to respond to environmental and social pressures, ensuring the maintenance of global food security. Therefore, there is an urgent demand for more sustainable agricultural practices that promote soil quality, as this factor directly impacts the global economy. Agricultural yield is directly associated with soil health and fertility. The use of organic waste serves as a source of essential nutrients for plants, increasing soil organic matter, contributing to the improvement of soil physical and chemical properties, as well as increasing crop yield. Based on this context, this research aimed to evaluate the effects of incorporating organic waste aiming to mitigate the oxidative damage in maize plants grown under different levels of soil fertility (low, average, and high), evaluating soil and plant, more specifically chemical, physiological, biochemical, and morphological responses. In soil, organic waste promoted significant increases in the activities of arylsulfatase and β-glucosidase and improved the chemical parameters, including cation exchange capacity, soil organic matter, base saturation, and sum of bases. The application of organic waste, regardless of fertility level, improved the nutritional status in maize plants, increased concentrations of photosynthetic pigments, maximized the photochemical efficiency and photosynthesis rate. In plant metabolism, the results demonstrated that organic waste promoted significant increases in plant antioxidant defense, including superoxide dismutase, catalase, ascorbate peroxidase, and peroxidase, minimizing the oxidative stress on photosynthetic machinery, especially in plants cultivated on soil with low fertility. Therefore, this research proves that organic waste mitigates the negative impacts associated with nutritional starvation, improves soil health and fertility, favors the maintenance of redox metabolism, and stimulates photosynthesis in maize plants cultivated in low-fertility soil.