The article discusses the use of biostimulant microalgae, known for their bioactive compounds. Understanding the positive impacts of biostimulants is essential for future applications. Research conducted in the Department of Plant Sciences at the Széchenyi István University has revealed that algae produce plant hormones and possess beneficial properties that influence the water, soil and plant systems. The effects of microalgae on various ornamental plants are being studied with a focus on improving root and general plant development. The methodology involves testing different algae extracts in ornamental plants in controlled environments. Data collection includes measuring plant height, leaf and bud numbers, chlorophyll content and other plant parameters through laboratory and destructive tests. The results indicate positive changes in plant parameters after treatments with biostimulant microalgae. In conclusion, biostimulant microalgae offer a promising and eco-friendly alternative to synthetic chemicals in the cultivation of ornamental plants. Continued research and innovation in this field is crucial to realise the full potential of biostimulants in sustainable agriculture.

Western corn rootworm is one of the most dangerous pests of maize, and both the larvae and the imagoes thereof may cause significant damage to the plants. The options of controlling these pests have recently become highly limited, thus creating a great demand for new control methods complying with sustainable plant protection. These requirements are met by the natural enemies of these pests, such as entomopathogenic nematodes (e.g. Heterorhabditis bacteriophora, Gerritsen, 1994). The objective of this study was to determine whether the viability and larvicide effect of a single injection into the soil of 2 billion nematodes using various amounts of water (50, 100 or 200 L/hectare) was maintained even with the lower quantities. Our studies proved that the entomopathogenic nematodes retain their viability and larvicide effect when applied using 50 L/ha of water. The efficacy of the biological agent did not differ from that of Force 1.5G, a product containing Tefluthrin as active ingredient, which was used as positive control.