BackgroundNebivolol is a third-generation beta-blocker used to treat hypertension. The vasodilation properties of nebivolol have been attributed to nitric oxide (NO) release. However, the kinetics and mechanism of nebivolol-stimulated bioavailable NO are not fully understood.MethodsUsing amperometric NO and peroxynitrite (ONOO-) nanosensors, β3-receptor (agonist: L-755,507; antagonists: SR59230A and L-748,337), ATP efflux (the mechanosensitive ATP channel blocker, gadolinium) and P2Y-receptor (agonists: ATP and 2-MeSATP; antagonist: suramin) modulators, superoxide dismutase and a NADPH oxidase inhibitor (VAS2870), we evaluated the kinetics and balance of NO and ONOO- stimulated by nebivolol in human umbilical vein endothelial cells (HUVECs). NO and ONOO- were measured with nanosensors (diameter ~ 300 nm) placed 5 ± 2 μm from the cell membrane and ATP levels were determined with a bioluminescent method. The kinetics and balance of nebivolol-stimulated NO and ONOO- were compared with those of ATP, 2-MeSATP, and L-755,507.ResultsNebivolol stimulates endothelial NO release through β3-receptor and ATP-dependent, P2Y-receptor activation with relatively slow kinetics (75 ± 5 nM/s) as compared to the kinetics of ATP (194 ± 10 nM/s), L-755,507 (108 ± 6 nM/s), and 2-MeSATP (105 ± 5 nM/s). The balance between cytoprotective NO and cytotoxic ONOO- was expressed as the ratio of [NO]/[ONOO-] concentrations. This ratio for nebivolol was 1.80 ± 0.10 and significantly higher than that for ATP (0.80 ± 0.08), L-755,507 (1.08 ± 0.08), and 2-MeSATP (1.09 ± 0.09). Nebivolol induced ATP release in a concentration-dependent manner.ConclusionThe two major pathways (ATP efflux/P2Y receptors and β3 receptors) and several steps of nebivolol-induced NO and ONOO- stimulation are mainly responsible for the slow kinetics of NO release and low ONOO-. The net effect of this slow kinetics of NO is reflected by a favorable high ratio of [NO]/[ONOO-] which may explain the beneficial effects of nebivolol in the treatment of endothelial dysfunction, hypertension, heart failure, and angiogenesis.

Winter oilseed rape is strongly responsive to changes in the plant density. Any change in plant density significantly affects the morphological characteristics and yield of the crop. In addition, plant growth habit can be modified by the use of plant growth regulators. Apart from plant growth regulators like eg. chlorocholine chloride some triazoles have dual properties (fungicide and plant growth regulator) eg. tebuconazole. The trials were carried out in the years 2006-2008 at the Institute of Plant Protection - National Research Institute in Poznan (Poland). The treatments consisted of chlorocholine chloride, tebuconazole and flusilazole applied in spring at the growth stage BBCH 30 and BBCH 50 of winter oilseed rape. The field trials were conducted with two sowing densities of winter oilseed rape: 60 seeds/ m2 and 120 seeds/m2. The vegetation seasons varied according to the weather conditions, and the second testing year was characterised by drought in May and June. In the experiments plant height, SPAD units, number of siliques per plant, seed number per silique, weight of thousand seeds, yield, protein and fat content in the seeds were estimated. The increase of silique numbers per plant appeared only at the lower sowing density as a result of the application of tebuconazole or a mixture of tebuconazole with CCC. Flusilazole had a positive impact on seed number per silique. At both sowing densities, changes in the weight of a thousand seeds under the influence of the test preparations, were observed only in that year which had wet weather conditions. A more favourable effect of the test substances on the weight of a thousand seeds was obtained at the lower sowing density. All the tested substances positively affected SPAD unit values at the lower sowing density. At the higher sowing density, SPAD unit values increased after the application of flusilazole, and after a mixture of CCC + tebuconazole. The tested substances had a positive impact on plant yield but they did not affect the protein and fat content in oilseed rape seeds.

Temperature strongly influences the growth of maize, particularly in the early growth stages. The exogenous application of some amino acids has been proven to have a positive effect on plant growth and development under stressful conditions. The objective of the study was to evaluate the response of maize that was grown under an optimal and stress (fluctuating) temperature to L-Arginine (L-Arg) and Glycine (Gly) application. In the study, it was assumed that the exogenously applied amino acids would alleviate the adverse effects of temperature stress on the maize height, as well as on the biomass of shoots and roots. Ten concentrations of each amino acid from 0.006 mM to 9.0 mM were tested under constant temperature conditions 20–22 °C/23–25 °C (night/day) an fluctuating stress of rising and dropping temperatures between 12–15 °C (night) and 30–38 °C (day). The amino acids were applied to the crop at growth stages V3–V4. In plants that were obtained from seeds pre-treated with L-Arg and Gly, the amino acids increased both the length of radicles and the number of lateral roots. A large discrepancy between the effects of the two amino acids was observed after foliar application. Under optimal thermal conditions, L-Arg increased the mass of shoots and roots by 55–59%. Under stress conditions, root mass was increased even by 100% when compared to the control plants. The best results were recorded at concentrations of 6 mM and 3 mM. Plants that were treated with Gly concentrations generally reached the height of untreated plants or less. It was shown that Gly applied at concentrations of 0.2 mM to 3 mM has a negative effect on the fresh mass of the crop.

Cinnamon is widely used as a food spice, but due to its antibacterial and pharmacological properties, it can also be used in processing, medicine and agriculture. The word “Cinnamon” can refer to the plant, processed material, or an extract. It is sometimes used as a substance, and sometimes used as a mixture or as compounds or a group. This article reviews research into the effectiveness of various forms of cinnamon for the control of plant diseases and pests in crops and during storage of fruit and vegetables. Cinnamon acts on pests mainly as a repellent, although in higher doses it has a biocidal effect and prevents egg-laying. Cinnamon and its compounds effectively hinder bacterial and fungal growth, and the phytotoxic effects of cinnamon make it a possible herbicide. This article presents the wide practical use of cinnamon for various purposes, mainly in agriculture. Cinnamon is a candidate for approval as a basic substance with protective potential. In particular, it can be used in organic farming as a promising alternative to chemical pesticides for use in plant protection, especially in preventive treatments. The use of natural products is in line with the restriction of the use of chemical pesticides and the principles of the EU’s Green Deal.

Alopecurus myosuroides seeds were sampled from 32 winter wheat fields from 2010 to 2014. Resistance to herbicides was detected in 17 A. myosuroides populations. In addition to single resistance to herbicides, cross-resistance and multiple resistance to acetolactate synthase (ALS)- and acetyl-coenzyme A carboxylase (ACCase)-inhibiting herbicides were found. Application of sulfometuron and imazapyr was unable to control some of the resistant biotypes in this study. This result implies that resistance in these populations is due to a target site mechanism. The A. myosuroides biotypes resistant to ACCase-inhibiting herbicides varied in their responses to derivatives of aryloxy-phenoxy-propionic acid (FOPs), cyclohexanediones (DIMs) and phenylpyrazolines (DENs). Resistant biotypes of A. myosuroides that could not be controlled with fenoxaprop-P-ethyl (FOP) and pinoxaden (DEN) were controlled with clethodim (DIM).