The physiological effects of fluid byproducts originating from a biogas factory located in Biharnagybajom (Eastern Hungary) were examined. While sustainable development is a requirement of environmental protection, agriculture must also carefully consider its aspects. One of the most important expectations regarding sustainable agriculture is the minimisation of the use of industrial chemicals. One possibility to minimise chemicals is the use of the byproducts of biogas factories. Crop plants extract huge amounts of nutrients from soils. In order to obtain the same yield – as regards both quality and quantity – it is necessary to replenish the extracted minerals that were harvested by plants with nutrients. Fluid byproducts contain several essential elements; therefore, they can be suitable in substituting industrial chemicals.

Maize (Zea mays L. cv. Norma SC) and sunflower (Helianthus annus L. Arena) seedlings were used in the experiments. The plants were grown in controlled environmental conditions. Different concentrations of fluid byproducts were examined during the experiment. The effect of the examined material depends on the concentrations of the applied byproduct. Dry matter accumulation of shoots and roots of maize, relative chlorophyll contents of the second and third leaves and the element contents were measured in the plants that were grown on nutrient solution.

Keywords: biogas, crop production, industrial byproduct, environmental, maize, sunflower