The increasing demand for sustainable agricultural practices has led researchers to explore alternative methods for controlling plant diseases and pests. Among these alternatives, essential oils (EOs) derived from various plant species have gained significant attention due to their broad-spectrum antimicrobial properties, which can be utilized in plant protection. Essential oils are volatile compounds that possess strong aromatic characteristics and are found in many medicinal and aromatic plants. They are known for their antifungal, antibacterial, and insecticidal activities, making them viable candidates for eco-friendly pest and disease management strategies. In this research, six essential oils—pine, patchouli, geranium, spruce, coriander, and eucalyptus oil—have been tested in vitro for controlling mycelium growth of Sclerotinia sclerotiorum, Botrytis cinerea, Alternaria brassicicola, and Cylindrosporium concentricum. The study also covers experiments in controlling pollen beetle and cabbage seed weevil (laboratory trials). In greenhouse conditions, the phytotoxicity of EOs to oilseed rape (Brassica napus L.) and the effect of these substances on the control of cornflower (Centaurea cyanus) were also tested. The results obtained indicate a large diversity of different essential oils in terms of their action on pathogens, pests, weeds, and winter rapeseed. Differences in their effectiveness were also found, depending on the applied dose.

Copper is a substance that has been used in plant protection for years. Currently, however, more and more attention is being paid to the need to limit the amount of it that ends up in the natural environment. At the same time, it is necessary to partially replace synthetic fungicides with alternative preparations. It is therefore worth looking for forms of copper that will contain a smaller amount of the mentioned ingredient while being highly effective. This experiment assessed the effect of selected preparations on the development of mycelium of pathogens of the Fusarium genus and the germination parameters of winter wheat. The efficacy of copper lignosulfonate and copper heptagluconate in seed treatment was tested, comparing them to copper oxychloride, copper hydroxide, and tebuconazole. The obtained results indicate that the use of copper lignosulfonate and copper heptagluconate allows for the effective limitation of the development of the tested pathogens (mycelium development was inhibited by up to 100%). Most of the preparations had no effect on the energy and germination capacity of winter wheat (only in one combination were the values lower than 90%). The use of preparations containing reduced doses of copper is an effective solution when applied as seed dressings.

Currently, researchers are looking for ways to replace synthetic pesticides with substances of natural origin. Essential oils are produced by plants, among other things, to protect against pathogens, which is why there is interest in their use as fungicides. This experiment assessed the composition of essential oils from a commercial source, their impact on the development of mycelium of pathogens of the Fusarium genus, and the possibility of using them as a pre-sowing treatment. Grains of winter wheat (Triticum aestivum L.) and corn (Zea mays L.) were inoculated with a suspension of mycelium and spores of fungi of the Fusarium genus and then soaked in solutions containing oils of sage (Salvia officinalis L.), cypress (Cupressus sempervirens L.), cumin (Cuminum cyminum L.), and thyme (Thymus vulgaris L.). The obtained results indicate that thyme essential oil had the strongest effect on limiting the development of Fusarium pathogens and seedling infection, but at the same time it had an adverse effect on the level of germination and seedling development of the tested plants. The remaining essential oils influenced the mentioned parameters to varying degrees. Selected essential oils can be an alternative to synthetic fungicides, but they must be selected appropriately.

This study investigates the biocontrol potential of Trichoderma asperellum and Coniothyrium minitans against the pathogen Sclerotinia sclerotiorum, which causes yield losses in many plants, including oilseed rape (Brassica napus) cultivation. This research emphasizes the promising alternative of hybrid control, specifically using T. asperellum and C. minitans in strategy with synthetic fungicides. In vitro experiments demonstrated that T. asperellum effectively inhibited S. sclerotiorum mycelial growth, especially when combined with synthetic fungicides such as azoxystrobin. Field trials conducted over two years revealed that pre-sowing applications of T. asperellum and C. minitans, followed by fungicide treatments during the flowering stage, significantly reduced plant infection rates and improved both yield and seed quality across different oilseed rape cultivars. The results indicated an efficacy range of 81% to 100% in controlling the pathogen and highlighted the synergistic effects of combining biological and chemical controls. Overall, the research findings support the integration of T. asperellum and C. minitans into sustainable agricultural practices for oilseed rape, offering a viable strategy to enhance disease management while reducing reliance on chemical fungicides. This research underscores the importance of adopting innovative biocontrol approaches to improve crop health and productivity.

Due to their multi-purpose use and, in many cases, lower requirements and financial outlays for cultivation, oats are an interesting crop. However, fungal diseases may contribute to significant declines in grain yields and quality. The aspects that may potentially influence this matter of fact include weather conditions. The aim of the study was to determine the severity of diseases caused by fungi in oat cultivation during the vegetation season. The next goal was to assess the efficacy of the selected active ingredients (a.i.) of fungicides from the chemical groups of triazoles and strobilurins in selected diseases’ control under various meteorological conditions. All of the fungicides were applied in the form of a spray treatment to reduce the severity of the diseases in the cultivation of different oat varieties. Husked and naked oat varieties were used. The health status of the oat plants was determined on the basis of a macroscopic evaluation of plants performed in accordance with the proper methodology. Field experiments were carried out under different weather conditions, which varied over the years during which the trials were conducted. Statistically significant differences were found in the reduction in infection for F and F1 leaves with D. avenae and P. coronata in comparison to the control treatment, regardless of the a.i. used. The use of a.i. tebuconazole (250 g/L), a.i. epoxiconazole (125 g/L), a.i. azoxystrobin (250 g/L) and a.i. picoxystrobin (250 g/L) enabled a reduction in the severity of oat helmintosporiosis in all years of the study for all the varieties analyzed. The efficacy was 72.4%, 74.2%, 71.5%, and 73.1%, respectively. Higher efficacy in reducing P. coronata was found in comparison with D. avenae. The obtained research results confirm the satisfactory efficacy of the above-mentioned active substances in reducing the fungi D. avenae and P. coronata.

Poland, like other countries in the world, increasingly experiences the ongoing climate change that is a critical yield-limiting factor. The use of biostimulants in agriculture has shown tremendous potential in combating climate change-induced stresses such as drought, temperature stress, etc. They could be a promising tool in the current crop production scenario. Biostimulants are organic compounds, microbes, or amalgamation of both that could regulate plant growth behavior through molecular alteration and physiological, biochemical, and anatomical modulations. They can promote plant growth under various environmental stresses because they have a positive effect, in particular, on plant growth and resistance. There are many products of this type available on the market, including those of natural origin, which are part of the Integrated Pest Management. The ecotoxicity of chemical plant protection products, the negative effects of their use, and the change in regulations make it recommended to use low-risk chemicals and non-chemical methods, that involve the least risk to health and the environment, and at the same time ensure effective and efficient protection of crops. Natural origin biocomponents obtained by the supercritical CO₂ extraction of plant material or by fermentation process in bioreactors were tested. Common maize (Zea mays L.) was selected as a test plant for growth tests at climate chambers. Results showed that the only supernatant (fermentation broth) obtained with the Paenibacillus bacteria (S2) had a positive effect on the germination index (GI > 100%) of maize seeds, compared to the obtained plant seed extracts from the crop of the legume family (Fabaceae) (E3) and from the crop of the smartweed family (Polygonaceae) (E9) (GI < 100%). The extracts E3, S1 (supernatant obtained with the use of bacteria from the genus Enterobacter) and S2 used as a single product and in combination with UAN+S, under optimal conditions of the experiment, had a positive effect on the maize root weight compared to the untreated, while under drought stress, a decrease in the root weight was observed. Moreover, on the basis of the conducted research, differences in the mycelial growth of selected fungi were found. The applied biocomponent S2 of microbial origin extract (supernatant 2) showed a mycelial growth-limiting effect on all tested Fusarium fungi isolated from the corn cobs.