The demand for soybeans in Europe motivates breeders, researchers, and growers to find suitable cultivars to adapt and extend the soybean crop to improper climate areas. Weed control is a crucial aspect of crop technology in organic agriculture, but particularly for soybean crops. In laboratory conditions, the cumulative stress index for seedlings was determined to identify the susceptible cultivars. A field experiment with 14 soybean accessions and 2 sowing dates was conducted under organic farming conditions over the course of three years, from 2020 to 2022. Plant population density was found to be significantly (p < 0.01 and p < 0.1) negatively correlated to the degree of resistance to low temperature as well as infestation degree with weeds (for p < 0.05 and p < 0.1), with the exception of early sowing in 2021. Yield was significantly (p < 0.05, p < 0.01, p < 0.1) correlated with plant population density, with the exception of optimal sowing in 2022. Early sowing variants emerged with vigor in the first two years, breeding lines and registered varieties showed low input, and organic agriculture systems showed low yields in the drought years of 2020 and 2022. Although early sowing even in the first two years proved to be a practice that increased the cultivars’ performance, in 2022, due to the long period of chilling stress in the field, this option had negative effects on yield due to the high weed frequency. Therefore, the early sowing strategy for the soybean crop in this particular case of non-irrigated conditions in a temperate continental area proved to be a risky practice.

Nitrogen is one of the most important nutrients for plants and is required by them in relatively large quantities. This paper presents an overview of scientific literature related to nitrogen management, with a specific highlight on permanent grasslands and has involved a bibliometric analysis of scientific literature regarding nitrogen management. The analysis was performed using the SCOPUS, which is an extensive database of literature all over the world, with wide coverage in keyword of analysis. For visualization and analysis, VOSviewer 1.6.18 was employed, which is an open access computer program, developed for creating bibliometric maps. The search results were downloaded as full record and citation data, with information related to document type, year of publication, title, author, keywords, abstract, references, funding agency, citations. A number of 3,948 articles were retrieved for analysis. The articles were sorted by relevance. The information was downloaded as .csv file and imported into VOSviewer 1.6.18 application software. Using the search query ”nitrogen management”, ”meadows” and ”pastures” indicated that 90% of the papers retrieved were research articles indexed in agricultural and biological sciences, followed by those in the environmental sciences, with themes of the ecosystem process, environmental management, land use, nitrogen fixation, organic nitrogen, soil structure, soil processing techniques.

An experiment was laid out on a Haplic Phaeozem (PH ha) (WRB-SR 2014) characterized by a dark colored mollic A horizon (Am), a cambic B horizon (Bv), and an accumulation calcareous illuviation horizon (Cca) of secondary calcium carbonates which occurs deeper than 125 cm (SRTS, 2012). Clay content in the first 40 cm varies between 39.4 and 42.6%, total nitrogen is 0.186%, available phosphorus soluble in the ammonium acetate lactate solution (PAL) 76 mg/kg, available potassium soluble in the same solution (KAL) 250 mg/kg, and soil reaction (pH) 6.3. The land is slightly uneven, groundwater below 5 m depth. The humus content was average in the beginning of the experimentations after which increases were noticed especially in the upper layer (5-10 cm). Soil humus content evolution following different agricultural technologies use was similar at all three studied depths, with increases in the case of minimum tillage system, but without statistically significant differences as compared to the classic one. Therefore, the various agricultural technological systems must assert the conservation and increase of soil organic matter, respectively the soil humus supply, through their technological chain links.