Search Results (3)

Various fertilization systems have been developed to optimize nitrogen (N) application, yet their effectiveness remains a topic of debate in both science and practice. This study evaluates the effects of 28 N fertilization treatments on yield, quality, nitrogen use efficiency (NUE), N surplus, and economic optima in two winter barley (Hordeum vulgare L.) varieties—a multi-row and a two-row type—across a three-year field trial (2021–2023). Specifically, it compares the performance of fertilizer requirement calculations based on the German Fertilizer Application Ordinance (GFO), multispectral sensor-based fertilization systems, and fixed N input treatments. Under the trial conditions (highly productive fields without organic fertilization for decades), the GFO system consistently achieved high yields (>10 t ha⁻¹) and NUE (up to 88%) for both barley varieties, often near economically optimal N rates and with minimal N surpluses. Sensor-based systems demonstrated promising potential for yield optimization and reducing N input; however, they did not result in significantly higher yields. Further research is needed to assess the performance of these fertilization systems under different conditions, such as sandy soils in regions with early-summer droughts or in systems involving organic fertilization. Full article

The consumption of contaminated fresh produce caused outbreaks of enterohemorrhagic (EHEC) Escherichia coli. Agricultural soil might be a reservoir for EHEC strains and represent a contamination source for edible plants. Furthermore, the application of manure as fertilizer is an important contamination route. Thus, the German fertilizer ordinance prohibits the use of manure 12 weeks before crop harvest to avoid pathogen transmission into the food chain. In this study, the survival of E. coli O104:H4 strain C227/11Φcu in soil microenvironments with either diluvial sand or alluvial loam at two temperatures was investigated for more than 12 weeks. It was analyzed whether the addition of cattle manure extends EHEC survival in these microenvironments. The experiments were additionally performed with isogenic ΔrpoS and ΔfliC deletion mutants of C227/11Φcu. The survival of C227/11Φcu was highest at 4 °C, whereas the soil type had a minor influence. The addition of cattle manure increased the survival at 22 °C. Deletion of rpoS significantly decreased the survival period under all cultivation conditions, whereas fliC deletion did not have any influence. The results of our study demonstrate that EHEC C227/11Φcu is able to survive for more than 12 weeks in soil microenvironments and that RpoS is an important determinant for survival. Full article

After repeated warnings by the European Commission regarding high nitrate concentrations in German waters, in 2017, Germany implemented a new fertilizer application ordinance (FO) with stricter nitrate value limits. The new regulations have severely affected agricultural regions in Germany and could lead to a high number of job losses if farmers must conform to the new regulations and do not implement new production methods. Therefore, a simulation game was developed to educate farmers and residents about the new FO and to facilitate adaptation to the new environmentally friendly legislation. The aims of the newly developed simulation game are to educate residents and farmers in affected regions about the new FO and to develop new ideas on how to comply with the new regulations. The aims of the present study are, first, to research participants’ evaluation of the simulation game and, second, to assess the effect of the simulation game on subjective knowledge, internal efficacy, and attitude towards the new FO. This pre- and post-comparison design study was based on pre-test and post-test with participants in two games (N = 90). The results were analyzed using descriptive statistics, multiple regression analyses, qualitative content analysis, and mean value comparisons. The simulation game had a positive effect on participants’ subjective knowledge (Cohen’s d 0.65) and internal efficacy (Cohen’s d 0.36), but it did not have an effect on their attitudes toward the new FO, and it was shown to slightly lower their interest in agriculture politics (Cohen’s d −0.33). The participants reported that the game made them more aware of both the difficulty and necessity of finding compromises in the field of agriculture politics. Overall, the simulation was rated very positively and was perceived as interesting and informative by the participants. Full article