Impact of Various Essential Oils on the Development of Pathogens of the Fusarium Genus and on Health and Germination Parameters of Winter Wheat and Maize.

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.

Impact of novel herbicide based on synthetic auxins and ALS inhibitor on weed control.

Delayed sowing of winter cereals or unfavorable weather conditions in autumn may make it impossible to carry out herbicide treatment in autumn. In such cases, weed control should be started in the spring. During this time, the plantation should be protected as effectively as possible because the weeds are at an advanced stage of growth. Therefore, they are less sensitive to applied herbicides. In the treatment, it is worth using a mixture of different mechanisms of action. Studies were conducted to evaluate the effectiveness of a band of tribenuron-methyl, and MCPA applied as soluble granules in spring control of dicotyledonous in winter cereals. The biological efficacy of herbicides was estimated in the 25 field experiments on winter cereals in Poland. Postemergence, a spring application of tribenuron-methyl + MCPA, effectively controls the majority of weed species present in spring: Anthemis arvensis, Brassica napus, Capsella bursa-pastoris, Centaurea cyanus, Lamium purpureum, Matricaria chamomilla, Tripleurospermum inodorum, Stellaria media and Thlaspi arvense. Satisfactory control was confirmed for Veronica persica, Viola arvensis, and Galium aparine. Tribenuron-methyl with MCPA is recommended for application to winter cereals in spring. To prevent the development of resistance in weeds, it is advantageous to combine two active substances.

A comprehensive study demonstrating the influence of the solvent composition on the phytotoxicity of compounds, as exemplified by 2,4-D-based ILs with a choline-type cation.

BACKGROUND: Growing concern for the protection of the environment and existing ecosystems has resulted in increasing consideration of phytotoxicity tests as valid ecotoxicological indicators of the potential hazards of the use of ionic liquids (ILs) or any other chemical. The objective of this study was to gain a detailed understanding of the influence of the solvent composition of spray solutions on the phytotoxic effect of foliar application of ionic pairs with weak (choline 2,4-dichlorophenoxyacetate, [Chol][2,4-D]), medium (N-hexylcholine 2,4-dichlorophenoxyacetate, [C6 Chol][2,4-D]) and good (N-dodecylcholine 2,4-dichlorophenoxyacetate, [C12 Chol][2,4-D]) surface-active properties. RESULTS: Experimental results unambiguously demonstrated that the biological activity of the test salt solutions, particularly [Chol][2,4-D] and [C6 Chol][2,4-D], can be strongly affected by the addition of an organic solvent, such as methanol, ethanol, dimethylformamide (DMF) or dimethylsulfoxide (DMSO) compared to solutions in pure water. However, the observed tendency is less pronounced for the compound exhibiting good surface activity, [C12 Chol][2,4-D]. CONCLUSIONS: The collected findings show that caution is warranted in the exploitation or modification of methodologies for assessing phytotoxicity to ensure the reliable interpretation of obtained results for environmental risk assessment or building quantitative structure-activity relationship (QSAR) models. © 2023 Society of Chemical Industry.

Hermetia illucens frass improves the physiological state of basil (Ocimum basilicum L.) and its nutritional value under drought.

To counterbalance the growing human population and its increasing demands from the ecosystem, and the impacts on it, new strategies are needed. Use of organic fertilizers boosted the agricultural production, but further increased the ecological burden posed by this indispensable activity. One possible solution to this conundrum is the development and application of more environmentally neutral biofertilizers. The aim of this study was to compare the effectiveness of two doses of Hermetia illucens frass (HI frass) with the commercial cattle manure in the cultivation of basil under drought. Soil without the addition of any organic fertilizer was used as a baseline control substrate for basil cultivation. Plants were grown with cattle manure (10 g/L of the pot volume) or HI frass at two doses (10 and 12.5 g/L). The health and physiological condition of plants were assessed based on the photosynthetic activity and the efficiency of photosystem II (chlorophyll fluorescence). Gas exchange between soil and the atmosphere were also assessed to verify the effect of fertilizer on soil condition. In addition, the mineral profile of basil and its antioxidant activity were assessed, along with the determination of the main polyphenolic compounds content. Biofertilizers improved the fresh mass yield and physiological condition of plants, both under optimal watering and drought, in comparison with the non-fertilized controls. Use of cattle manure in both water regimes resulted in a comparably lower yield and a stronger physiological response to drought. As a result, using HI frass is a superior strategy to boost output and reduce the effects of drought on basil production.

Succinate dehydrogenase inhibitor seed treatments positively affect the physiological condition of maize under drought stress.

Improvements in agricultural production are needed, as the growing human population demands more resources and exerts stronger effects on climate. Water scarcity is one of the main factors limiting the yield of maize in many regions of the world. One possible method to mitigate the negative effects of drought is seed mortars; its use improves plant development from the early stages onwards. In this study, we tested 12 various seed treatments with and without succinate dehydrogenase inhibitors (SDHI; sedaxane) on maize "SY Fanatic." Physiological parameters of germinating seeds, of young maize seedlings under drought, and of seedlings recuperated from drought were assessed and compared across 12 seed treatments and with non-stressed plants. The seed treatments varied greatly in their influence on the germination and the physiological state of seedlings under drought and after regeneration. Seeds under treatments No. 6, 11, and 12 showed the highest germination energy (97.3%). The use of SDHI-containing seed treatments significantly improved the development of the maize root system. The longest roots, ~13 cm in length, were recorded for treatments No. 6 and 12, both containing sedaxane. These treatments also boosted the functioning of plants growing under optimal soil moisture conditions and under drought stress, influencing the photosynthesis process, increasing the absorption of CO2, and improving the parameters of chlorophyll fluorescence in relation to non-treated controls. Our data indicated that using substances from the SDHI group can possibly reduce the drought-related stress reactions in maize, helping this important crop to face the progressing climate change.

Iodosulfuron-Methyl-Based Herbicidal Ionic Liquids Comprising Alkyl Betainate Cation as Novel Active Ingredients with Reduced Environmental Impact and Excellent Efficacy.

A new family of bio-based herbicidal ionic liquids (HILs) has been synthesized starting from the renewable resource glycine betaine (a derivative of natural amino acids). After esterification, the obtained alkyl betainate bromides containing straight alkyl chains varying from ethyl to octadecyl were combined with a herbicidal anion from the sulfonylurea group (iodosulfuron-methyl). The melting points of the iodosulfuron-methyl-based salts were in a range from 51 to 99 °C, which allows their classification as ionic liquids (ILs). In addition, the new HILs exhibited good affinity for polar and semipolar organic solvents, such as DMSO, methanol, acetonitrile, acetone, and chloroform, while the presence of bulky organic cations reduced their solubility in water. The synthesized products turned out to be stable during storage at 25 °C for over 6 months; however, at 75 °C they underwent fast, progressive degradation and released volatile byproducts. The values of the logarithm of the octanol-water partition coefficient of ILs with alkyls longer than hexyl occurred in the "safe zone" (between 0 and 3); hence, the risk of their migration into groundwater after application or the possibility of their bioaccumulation in the environment is lower in comparison with the currently available commercial form (iodosulfuron-methyl sodium salt). Greenhouse studies confirmed a very high herbicidal efficacy for the obtained salts toward tested plants of oilseed rape, indicating that they may become an attractive replacement for the currently available sulfonylurea-based formulations.