Sondersammlungen

Permanent URI for this communityhttps://hohpublica.uni-hohenheim.de/handle/123456789/7011

Browse

Now showing 1 - 14 of 14

A diamine oxidase from Glutamicibacter halophytocola for the degradation of histamine and tyramine in foods
(2025) Kettner, Lucas; Freund, Alexander; Bechtel, Anna; Costa-Catala, Judit; Fischer, Lutz; Kettner, Lucas; Department of Biotechnology and Enzyme Science, Institute of Food Science and Biotechnology, University of Hohenheim, Garbenstr. 25, 70599 Stuttgart, Germany; Freund, Alexander; Department of Biotechnology and Enzyme Science, Institute of Food Science and Biotechnology, University of Hohenheim, Garbenstr. 25, 70599 Stuttgart, Germany; Bechtel, Anna; Department of Biotechnology and Enzyme Science, Institute of Food Science and Biotechnology, University of Hohenheim, Garbenstr. 25, 70599 Stuttgart, Germany; Costa-Catala, Judit; Departament de Nutrició, Ciències de l’Alimentació i Gastronomia, Campus de l’Alimentació de Torribera, Universitat de Barcelona, Av. Prat de la Riba 171, 08921 Santa Coloma de Gramenet, Spain; Fischer, Lutz; Department of Biotechnology and Enzyme Science, Institute of Food Science and Biotechnology, University of Hohenheim, Garbenstr. 25, 70599 Stuttgart, Germany
A novel diamine oxidase (DAO) was discovered in the bacterium Glutamicibacter halophytocola (DAO-GH). The gene of DAO-GH was integrated into the genome of the yeast Komagataella phaffii and recombinantly produced under control of the methanol-inducible AOX1 promoter in a bioreactor cultivation. A high DAO activity of 70.2 ± 5.2 µkat/Lculture (5.25 ± 0.22 µkat/gprotein) was yielded after 90 h of cultivation. The DAO-GH was partially purified by the polyethyleneimine precipitation of nucleic acids, fractionated ammonium sulfate precipitation and hydrophobic interaction chromatography, resulting in a specific DAO activity of 19.7 µkat/gProtein. The DAO-GH was then biochemically investigated regarding its potential for histamine and tyramine degradation in fermented foods and the human small intestine. Interestingly, the DAO-GH showed activity even at a low pH of 5 and low temperature of 6 °C. Both histamine and tyramine were effectively degraded and DAO-GH showed especially very high affinity towards tyramine (Km of 0.009 mM). The DAO-GH was shown to be capable of degrading around 20% of the initially applied histamine in tuna paste (pH 5.6) at 5 °C within 24 h and completely degraded the histamine in a simulated intestinal fluid within 1.5 h in bioconversion experiments. The DAO-GH was spray-dried for the production of a storable enzyme preparation. Only around 17% of activity were lost in this process and the DAO-GH remained stable at room temperature for at least 3 months. The discovery of this DAO with its very advantageous biochemical properties allows the preparation of histamine-reduced or -free fermented foods by a simple enzymatic treatment or the treatment of histamine intolerance symptoms as a dietary supplement or medicine.
Expression of fibroblast growth factor 23 (FGF23) and αKlotho in two commercial laying hen strains fed with and without dietary mineral P supplements before and after the onset of the laying phase
(2025) Meier, Leonie; Wallauch, Nadine; Feger, Martina; Oster, Michael; Sommerfeld, Vera; Schmucker, Sonja; Wimmers, Klaus; Huber, Korinna; Stefanski, Volker; Rodehutscord, Markus; Föller, Michael
Maintenance of phosphate homeostasis is particularly critical in laying hens for bone formation and calcium mobilization. The supplementation of their feed with mineral phosphate is common although recent research questions the usual levels of supplementation. Phosphate homeostasis is classically regulated by active vitamin D (calcitriol) and parathyroid hormone, whereas fibroblast growth factor 23 (FGF23) and its co-receptor αKlotho are novel factors. FGF23 has emerged as an important disease biomarker and αKlotho as an anti-aging factor in mammals, however, little is known about their role in poultry. Here, we studied FGF23 and αKlotho expression in two commercial laying hen strains under conditions of dietary mineral phosphorus renunciation and sufficient phosphorus supply. Fifteen- and 20-week-old Lohmann Brown-Classic (LB) or LSL-Classic (LSL) hens were fed a standard maize-soybean-based diet containing 0 or 1 g/kg additional mineral phosphorus for 4 weeks. The animals were sacrificed, and gene expression studied in different organs by quantitative real-time PCR and protein expression by western blotting. Statistical correlation with further parameters of mineral metabolism was analyzed by Pearson’s correlation coefficient or Spearman’s Rho. As a result, FGF23 bone expression was significantly lower and hepatic FGF23 expression higher in 24-week-old than in 19-week-old hens. Bone, hepatic, and renal αKlotho expression was significantly higher in older than younger animals. Compared to LB hens, LSL hens exhibited higher hepatic αKlotho irrespective of diet and age. Dietary phosphorus content did not significantly affect FGF23 and αKlotho expression. Bone FGF23 expression was positively and hepatic FGF23 negatively associated with plasma phosphate concentration whereas bone FGF23 expression was negatively and hepatic FGF23 positively associated with plasma calcitriol concentration. To conclude, we uncovered a strong impact of age and strain on FGF23 and αKlotho expression in two high performance laying hen strains, effects possibly associated with initiation of the egg-laying phase. Moreover, the regulation of hepatic FGF23 expression differed from the regulation of bone FGF23 expression. Further studies are needed to elucidate the physiological relevance.
Iron partitioning and photosynthetic performance in Cannabis sativa L. reveal limitations of nanoscale zero-valent iron as a fertilizer
(2025) Büser, Christian; Hartung, Jens; Deurin, Lukas; Graeff-Hönninger, Simone
Iron (Fe) is the fourth most abundant element in the Earth’s crust but remains the third most limiting nutrient for crop productivity due to its low solubility in most soils. The emergence of nanotechnology has introduced nanoscale zero-valent iron (nZVI) as a potential Fe fertilizer with high surface reactivity and improved bioavailability. However, its comparative efficacy relative to conventional chelated Fe sources remains poorly understood. This study investigated Fe partitioning, photosynthetic efficiency, biomass accumulation, and cannabinoid synthesis in Cannabis sativa L. grown hydroponically under Fe-EDTA, nZVI, or Fe-deficient (-Fe) treatments. Total Fe concentrations were markedly reduced in -Fe plants compared with both Fe-EDTA and nZVI treatments. Despite similar root Fe contents between Fe-EDTA and nZVI, only Fe-EDTA facilitated efficient translocation to shoots, while nZVI-derived Fe predominantly accumulated in roots. Consequently, nZVI-treated plants exhibited intermediate photosynthetic performance and water-use efficiency—lower than Fe-EDTA but significantly higher than -Fe. Although Fe translocation differed substantially, inflorescence biomass and cannabinoid yield were comparable between nZVI and Fe-EDTA treatments, both exceeding those of -Fe plants. These results suggest that yield reductions under Fe deficiency arise not solely from Fe scarcity but also from the metabolic costs of Strategy I Fe acquisition, which are partially circumvented by root Fe availability from nZVI. Overall, Fe-EDTA demonstrated superior nutrient use efficiency, whereas nZVI partially alleviated Fe deficiency and revealed distinctive interactions between nanomaterials and plant Fe physiology. This study advances understanding of nZVI as an alternative Fe source in C. sativa and provides new insights into nanoparticle–plant nutrient dynamics.
Limitations of soil-applied non-microbial and microbial biostimulants in enhancing soil P turnover and recycled P fertilizer utilization: A study with and without plants
(2024) Herrmann, Michelle Natalie; Griffin, Lydia Grace; John, Rebecca; Mosquera-Rodríguez, Sergio F.; Nkebiwe, Peteh Mehdi; Chen, Xinping; Yang, Huaiyu; Müller, Torsten
Introduction: Phosphorus recovery from waste streams is a global concern due to open nutrient cycles. However, the reliability and efficiency of recycled P fertilizers are often low. Biostimulants (BS), as a potential enhancer of P availability in soil, could help to overcome current barriers using recycled P fertilizers. For this, a deeper understanding of the influence of BSs on soil P turnover and the interaction of BSs with plants is needed. Methods: We conducted an incubation and a pot trial with maize in which we testednon-microbial (humic acids and plant extracts) and microbial BSs (microbial consortia) in combination with two recycled fertilizers for their impact on soil P turnover, plant available P, and plant growth. Results and discussion: BSs could not stimulate P turnover processes (phosphatase activity, microbial biomass P) and had a minor impact on calcium acetate-lactate extractable P (CAL-P) in the incubation trial. Even though stimulation of microbial P turnover by the microbial consortium and humic acids in combination with the sewage sludge ash could be identified in the plant trial with maize, this was not reflected in the plant performance and soil P turnover processes. Concerning the recycled P fertilizers, the CAL-P content in soil was not a reliable predictor of plant performance with both products resulting in competitive plant growth and P uptake. While this study questions the reliability of BSs, it also highlights the necessity toimprove our understanding and distinguish the mechanisms of P mobilization in soil and the stimulation of plant P acquisition to optimize future usage.
Mapping genes for resilient dairy cows by means of across-breed genome-wide association analysis
(2025) Keßler, Franziska; Zölch, Maximilian; Wellman, Robin; Bennewitz, Jörn; Keßler, Franziska; Institute of Animal Science, University of Hohenheim, Garbenstr. 17, 70599, Stuttgart, Germany; Zölch, Maximilian; Institute of Animal Science, University of Hohenheim, Garbenstr. 17, 70599, Stuttgart, Germany; Wellman, Robin; Institute of Animal Science, University of Hohenheim, Garbenstr. 17, 70599, Stuttgart, Germany; Bennewitz, Jörn; Institute of Animal Science, University of Hohenheim, Garbenstr. 17, 70599, Stuttgart, Germany
Background: Indicator traits based on variance and autocorrelation of longitudinal data are increasingly used to measure resilience in animal breeding. While these traits show promising heritability and can be routinely collected, their genetic architecture remains poorly understood. We conducted GWAS for three resilience indicators across German Holstein ( n = 2,300), Fleckvieh ( n = 2,330), and Brown Swiss ( n = 1,073) dairy cattle ( Bos Taurus ) populations. The indicators included variance ( ) and autocorrelation ( ) of deviations of observed from predicted daily milk yield and variance of relative daily milk yield ( ). Additionally, we analysed a selection index combining these traits. Prior to GWAS, we examined population structure through multi-dimensional scaling (MDS) and LD patterns, revealing distinct genetic clusters for each breed and similar LD decay patterns. Results: The GWAS results confirmed the polygenic nature of resilience, with multiple genomic regions showing significant associations. Notable signals were detected on BTA5 ( ), BTA14 ( ), BTA2 and BTA8 ( ) for single indicator traits. For selection index resilience, strong suggestive SNPs are located on BTA4 , BTA16 , BTA21 , and BTA27 . Detected regions overlapped with previously reported QTLs for performance, reproduction, longevity and health, providing new insights into the biological pathways underlying dairy cattle resilience. Conclusions: Our findings demonstrate that resilience indicators have a complex genetic architecture with both breed-specific and shared components, supporting their potential use in selective breeding programs while highlighting the importance of careful trait definition.
Microbial inoculants modulate the rhizosphere microbiome, alleviate plant stress responses, and enhance maize growth at field scale
(2025) Francioli, Davide; Kampouris, Ioannis D.; Kuhl-Nagel, Theresa; Babin, Doreen; Sommermann, Loreen; Behr, Jan H.; Chowdhury, Soumitra Paul; Zrenner, Rita; Moradtalab, Narges; Schloter, Michael; Geistlinger, Joerg; Ludewig, Uwe; Neumann, Günter; Smalla, Kornelia; Grosch, Rita
Background: Field inoculation of crops with beneficial microbes is a promising sustainable strategy to enhance plant fitness and nutrient acquisition. However, effectiveness can vary due to environmental factors, microbial competition, and methodological challenges, while their precise modes of action remain uncertain. This underscores the need for further research to optimize inoculation strategies for consistent agricultural benefits. Results: Using a comprehensive, multidisciplinary approach, we investigate the effects of a consortium of beneficial microbes (BMc) ( Pseudomonas sp. RU47, Bacillus atrophaeus ABi03, Trichoderma harzianum OMG16) on maize ( Zea mays cv. Benedictio) through an inoculation experiment conducted within a long-term field trial across intensive and extensive farming practices. Additionally, an unexpected early drought stress emerged as a climatic variable, offering further insight into the effectiveness of the microbial consortium. Our findings demonstrate that BMc root inoculation primarily enhanced plant growth and fitness, particularly by increasing iron uptake, which is crucial for drought adaptation. Inoculated maize plants show improved shoot growth and fitness compared to non-inoculated plants, regardless of farming practices. Specifically, BMc modulate plant hormonal balance, enhance the detoxification of reactive oxygen species, and increase root exudation of iron-chelating metabolites. Amplicon sequencing reveals shifts in rhizosphere bacterial and fungal communities mediated by the consortium. Metagenomic shotgun sequencing indicates enrichment of genes related to antimicrobial lipopeptides and siderophores. Conclusions: Our findings highlight the multifaceted benefits of BMc inoculation on plant fitness, significantly influencing metabolism, stress responses, and the rhizosphere microbiome. These improvements are crucial for advancing sustainable agricultural practices by enhancing plant resilience and productivity.
Occurrence and quantification of porcine hemotrophic mycoplasmas in blood-sucking Stomoxys calcitrans
(2025) Arendt, Mareike; Hoelzle, Katharina; Stadler, Julia; Ritzmann, Mathias; Ade, Julia; Hoelzle, Ludwig E.; Schwarz, Lukas; Rossi, Franca
Hemotrophic mycoplasmas (HMs) are cell wall-less, small and uncultivable pathogens, which can cause infections in pigs with no to severe clinical signs and can contribute to significant economic losses in the pig industry. In addition to the known mechanical transmission routes of HMs (e.g., via blood-contaminated instruments or lesions from ranking fights), transmission to pigs by arthropod vectors such as Stomoxys calcitrans is being discussed. To date, there is scant available data concerning the transmission of HMs by stable flies. The objective of this study is to gain more data concerning the occurrence of HMs in Stomoxys calcitrans . Therefore, quantitative real-time PCR was conducted on different stable fly samples (surface washings and whole flies). We found Mycoplasma ( M. ) suis in 5.2% of crushed flies and 4.2% of fly wash solutions, and M. parvum was detected in 5.2% of flies and 9.4% of fly wash solutions. ‘ Candidatus ( Ca .) M. haemosuis’ was not detected in any sample. The mean bacterial loads were 2.0 × 10 2 M. suis /fly, 9.3 × 10 2 M. suis /fly wash solution and, for M. parvum , 2.4 × 10 3 M. parvum /fly and 2.1 × 10 3 M. parvum /fly wash solution. This molecular occurrence of porcine HMs in blood-sucking flies and reasonable bacterial loads in the two- to three-digit range demonstrate that these flies serve as mechanical vectors in stables and are, therefore, of epidemiological importance.
Pathways for biodiversity enhancement in German agricultural landscapes
(2025) Sponagel, Christian; Thompson, Amibeth; Paetow, Hubertus; Mupepele, Anne‐Christine; Bieling, Claudia; Sommer, Martin; Klein, Alexandra‐Maria; Settele, Josef; Finger, Robert; Huber, Robert; Albert, Christian; Filser, Juliane; Jansen, Florian; Kleemann, Janina; Schreiner, Vera; Lakner, Sebastian; Sponagel, Christian; Department of Farm Management, University of Hohenheim, Stuttgart, Germany; Thompson, Amibeth; Nature Conservation and Landscape Ecology, University of Freiburg, Freiburg, Germany; Paetow, Hubertus; DLG e.V.—German Agricultural Society, Frankfurt am Main, Germany; Mupepele, Anne‐Christine; Department of Biology—Animal Ecology, University of Marburg, Marburg, Germany; Bieling, Claudia; Department of Societal Transition and Agriculture, University of Hohenheim, Stuttgart, Germany; Sommer, Martin; Deutscher Verband für Landschaftspflege (DVL)—Landcare Germany, Ansbach, Germany; Klein, Alexandra‐Maria; Nature Conservation and Landscape Ecology, University of Freiburg, Freiburg, Germany; Settele, Josef; German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐Leipzig, Leipzig, Germany; Finger, Robert; Agricultural Economics and Policy, ETH Zürich, Zürich, Switzerland; Huber, Robert; Agricultural Economics and Policy, ETH Zürich, Zürich, Switzerland; Albert, Christian; Institute of Environmental Planning, Leibniz University Hannover, Hannover, Germany; Filser, Juliane; Center for Environmental Research and Sustainable Technology (UFT), University of Bremen, Bremen, Germany; Jansen, Florian; Faculty of Agricultural and Environmental Sciences, University of Rostock, Rostock, Germany; Kleemann, Janina; German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐Leipzig, Leipzig, Germany; Schreiner, Vera; Department of Sustainable Landscape Development, Institute for Geosciences and Geography, Martin‐Luther University Halle‐Wittenberg, Halle, Germany; Lakner, Sebastian; Faculty of Agricultural and Environmental Sciences, University of Rostock, Rostock, Germany
Conserving biodiversity, especially in agricultural landscapes, is a major societal challenge. Broad scientific evidence exists on the impacts of single drivers on biodiversity, such as the intensification of agriculture. However, halting biodiversity decline requires a systemic understanding of the interactions between multiple drivers, which has hardly been achieved so far. Selecting Germany as a case study, the goal of our analysis is (i) to understand how various socio‐economic drivers of biodiversity in agricultural landscapes interact at the national scale, (ii) to identify plausible pathways that most likely will lead to an improvement of biodiversity in agricultural landscapes and (iii) to discuss guiding principles for policy‐making based on the pathways. We applied the expert‐based Cross‐Impact‐Balance (CIB) methodology to the German agri‐food system (target year 2030). Seven descriptors that represent the most relevant socio‐economic drivers of biodiversity (here, we focus on species richness) in agricultural landscapes in Germany were defined. In three workshops with different groups of experts, we assessed all the interactions and impacts between these descriptors. From the workshops, seven overlapping scenarios were identified and aggregated into four main future pathways for enhancing biodiversity in agricultural landscapes. These pathways are: (1) ‘Innovation and stricter legislation’, (2) ‘Major change in protein production and CAP shift’, (3) ‘Major change in protein production and national legislation’ and (4) ‘Major social changes compensate for a lack of innovation in food production’. Socio‐economic drivers interact to varying degrees. Societal values have a strong active influence on the system, e. g. agricultural policy, whereas the orientation and objectives of agriculture, e. g. focus on public goods, are rather passively determined. Conserving biodiversity thus depends upon the evolution of societal values, European and national nature conservation and agricultural policies, innovations in plant and protein production as well as on global commodity markets. A key message for policymakers is that there are generally different, complementary options for achieving the objective of improving biodiversity. This is important when specific drivers such as the CAP cannot be steered in a particular desired direction.
Poultry perfection : comparison of computer vision models to detect and classify poultry products in a production setting
(2025) Einsiedel, Daniel; Vita, Marco; Jox, Dana; Dunnewind, Bertus; Meulendijks, Johan; Krupitzer, Christian
This study explores the use of computer vision, specifically object detection, for quality control in ready-to-eat meat products. We focused on a single process step, labeling products as “good” or “imperfect”. An “imperfect product” constitutes a product that deviates from the norm regarding shape, size, or color (having a hole, missing edges, dark particles, etc.). Imperfect does not mean the product is inedible or a risk to food safety, but it affects the overall product quality. Various object detectors, such as YOLO, including YOLO12, were compared using the mAP50-95 metric. Most models achieved mAP scores over 0.9, with YOLO12 reaching a peak score of 0.9359. The precision and recall curves indicated that the model learned the “imperfect product” class better, most likely due to its higher representation. This underscores the importance of a balanced dataset, which is challenging to achieve in real-world settings. The confusion matrix revealed false positives, suggesting that increasing dataset volume or hyperparameter tuning could help. However, increasing the dataset volume is usually the more difficult path since data acquisition and especially labeling are by far the most time-consuming steps of the whole process. Overall, current models can be applied to quality control tasks with some margin of error. Our experiments show that high-quality, consistently labeled datasets are potentially more important than the choice of the model for achieving good results. The applied hyperparameter tuning on the YOLO12 model did not outperform the default model in this case. Future work could involve training models on a multi-class dataset with hyperparameter optimization. A multi-class dataset could contain more specific classes than just “good” and “imperfect,” making trained models capable of actually predicting specific quality deviations.
The role of biodiversity in consumer research on food : a review and research agenda
(2025) Schneider, Deborah; Osieja, Sanja; Herbes, Carsten; Weinrich, Ramona
The move towards sustainable consumption has drawn significant attention from scholars and practitioners alike. Biodiversity is an integral part of environmental sustainability and food security, but it has received little attention in consumer research. Findings are fragmented into how biodiversity as a product attribute affects consumer food choices. Thus, we conducted a systematic literature review on consumer research on biodiversity in the context of food choice. We reviewed 45 papers published between 2014 and March 2025. Our analysis was guided by the TCCM (Theories, Contexts, Characteristics, and Methodology) framework for developing a systematic literature review. We examined how biodiversity was conceptualized and defined within the studies and towards study participants. Our findings show that biodiversity as a product attribute generally has positive effects on consumer attitude, willingness to pay, and product choice. However, knowledge about biodiversity and the inherent trade-offs in product choices remains limited, so consumers cannot realistically factor biodiversity into their decision-making. We find that research has taken a narrow view of biodiversity, qualitative studies are rare, and few efforts have been made to build theoretical perspectives from empirical data. We conclude with a proposed agenda for future research and a tentative definition of biodiversity for social science.
Should we delay leaf water potential measurements after excision? Dehydration or equilibration?
(2024) Perera‐Castro, Alicia V.; Puértolas, Jaime; Fernández-Marín, Beatriz; González-Rodríguez, Águeda M.; Perera-Castro, Alicia V.; Department of Botany, Ecology and Plant Physiology, Universidad de La Laguna (ULL), 38200, La Laguna, Canary Islands, Spain; Puértolas, Jaime; Department of Botany, Ecology and Plant Physiology, Universidad de La Laguna (ULL), 38200, La Laguna, Canary Islands, Spain; Fernández-Marín, Beatriz; Department of Botany, Ecology and Plant Physiology, Universidad de La Laguna (ULL), 38200, La Laguna, Canary Islands, Spain; González-Rodríguez, Águeda M.; Department of Botany, Ecology and Plant Physiology, Universidad de La Laguna (ULL), 38200, La Laguna, Canary Islands, Spain
Background: Accurate leaf water potential (Ψw) determination is crucial in studying plant responses to water deficit. After excision, water potential decreases, even under low evaporative demand conditions, which has been recently attributed to the equilibration of pre-excision Ψw gradients across the leaf. We assessed the influence of potential re-equilibration on water potential determination by monitoring leaf Ψw and relative water content decline after excision using different storage methods. Results: Even though leaf Ψw declined during storage under low evaporative demand conditions, this was strongly reduced when covering the leaf with a hydrophobic layer (vaseline) and explained by changes in relative water content. However, residual water loss was variable between species, possibly related to morpho-physiological leaf traits. Provided water loss was minimized during storage, pre-excision leaf transpiration rate did not affect to the magnitude of leaf Ψw decline after excision, confirming that transpiration-driven Ψw gradients have no effect on leaf Ψw determination. Conclusions: Disequilibrium in water potentials across a transpiring leaf upon excision is dissipated very quickly, well within the elapsed time between excision and pressurization, therefore, not resulting in overestimation of leaf Ψw measured immediately after excision. When leaf storage is required, the effectiveness of a storage under low evaporative demand varied among species. Covering with a hydrophobic layer is an acceptable alternative.
Spatiotemporal climatic signals in cereal yield variability and trends in Ethiopia
(2025) Abera, Kidist; Gayler, Sebastian; Piepho, Hans‑Peter; Streck, Thilo; Abera, Kidist; Institute of Soil Science and Land Evaluation, Biogeophysics, University of Hohenheim, Stuttgart, Germany; Gayler, Sebastian; Institute of Soil Science and Land Evaluation, Biogeophysics, University of Hohenheim, Stuttgart, Germany; Piepho, Hans‑Peter; Biostatistics Unit, Institute of Crop Science, University of Hohenheim, Stuttgart, Germany; Streck, Thilo; Institute of Soil Science and Land Evaluation, Biogeophysics, University of Hohenheim, Stuttgart, Germany
Climatic variability and recurrent drought can strongly affect the variability of crop yield and are therefore frequently considered a risk to food security in Ethiopia. A better understanding of how crop yields vary in space and time, and their relationship to climatic and other driving factors, can assist in enhancing agricultural production and adapting to and mitigating the impacts of climate change. We applied a multiple linear regression model to examine the spatiotemporal climatic signal (air temperature, precipitation, and solar radiation) in the yields of the most important crops (maize, sorghum, tef, and wheat) over the period 1995–2018. An analysis of the climatic data indicated that growing season temperature increased significantly in most regions, but the trends in precipitation were not significant. The yields of maize, sorghum, tef, and wheat tended to increase across most crop-growing areas, particularly in the west, but was highly variable. The results highlight large spatial differences in the contribution of climatic trends to crop-yield variability across Ethiopian regions. The trends in climatic variability did not significantly affect crop yields in some areas, whereas in the main crop-growing areas, up to − 39.2% of yield variability could be attributed to the climatic trends. Specifically, the climatic trends negatively affected maize yields but positively affected sorghum, tef, and wheat yields. Nationally, the average impacts of climatic trends on crop yields was relatively small, ranging from a 3.2% decrease for maize to a 0.7% increase for wheat. In contrast, technological advancements contributed substantially more to yield gains, with annual increases ranging from 4.3% for wheat to 5.1% for sorghum. These findings highlight the dominant role of non-climatic drivers, particularly improved agricultural technology, in shaping crop yield trends. Our findings underscore the spatial heterogeneity of climate impacts on agriculture and highlight the critical importance of technological progress in enhancing crop productivity. They also provide actionable insights for designing crop- and location-specific adaptation strategies, and stress the need for integrated, climate-resilient development pathways in the region.
Sulfate enhances metabolic acclimation under drought stress - a comparative study of grapevine and maize
(2025) Lehr, Patrick Pascal; Erban, Alexander; Kopka, Joachim; Zörb, Christian
The importance of sulfate fertilization in plant production has becoming increasingly relevant due to the decline in atmospheric sulfur inputs. Moreover, high-intensity cropping systems are increasingly facing drought scenarios. The role of stomata is crucial during drought stress and is linked to sulfate metabolism. This study investigates the impact of sulfate application on the drought response of grapevine and maize guard cells. Both plant species may serve as crop model for analysing underlying physiological processes in a low fertilizer demanding crop such as grapevine and a high fertilizer demanding crop such as maize. Increased sulfate concentration in leaves was triggered by drought in maize and grapevine, but in grapevine only when additional sulfate was applied. Additional sulfate application improved sulfur availability under drought conditions, which enhanced drought stress response in grapevine and maize. This was characterized by enhanced metabolic acclimation under drought conditions. The effect of sulfate on the drought stress response was markedly diminished in guard cells, indicating enhanced metabolic stability of guard cells against external influences. These results underscore the significance of adequate sulfate supply to crops for optimal drought stress response and suggest that sulfate fertilisation may serve as a potential option to enhance drought acclimation
The tale of two Ions Na⁺ and Cl⁻: unraveling onion plant responses to varying salt treatments
(2024) Romo-Pérez, Maria Luisa; Weinert, C. H.; Egert, B.; Kulling, S. E.; Zörb, Christian; Romo-Pérez, M. L.; University of Hohenheim, Institute of Crop Science, Quality of Plant Products 340e, Schloss Westflügel, 70599, Stuttgart, Germany; Weinert, C. H.; Department of Safety and Quality of Fruit and Vegetables, Max Rubner-Institut, Haid-und-Neu-Straße 9, 76131, Karlsruhe, Germany; Egert, B.; Department of Safety and Quality of Fruit and Vegetables, Max Rubner-Institut, Haid-und-Neu-Straße 9, 76131, Karlsruhe, Germany; Kulling, S. E.; Department of Safety and Quality of Fruit and Vegetables, Max Rubner-Institut, Haid-und-Neu-Straße 9, 76131, Karlsruhe, Germany; Zörb, C.; University of Hohenheim, Institute of Crop Science, Quality of Plant Products 340e, Schloss Westflügel, 70599, Stuttgart, Germany
Background: Exploring the adaptive responses of onions ( Allium cepa L.) to salinity reveals a critical challenge for this salt-sensitive crop. While previous studies have concentrated on the effects of sodium (Na⁺), this research highlights the substantial yet less-explored impact of chloride (Cl⁻) accumulation. Two onion varieties were subjected to treatments with different sodium and chloride containing salts to observe early metabolic responses without causing toxicity. Results: The initial effects of salinity on onions showed increased concentrations of both ions, with Cl⁻ having a more pronounced impact on metabolic profiles than Na⁺. Onions initially adapt to salinity by first altering their organic acid concentrations, which are critical for essential functions such as energy production and stress response. The landrace Birnförmige exhibited more effective regulation of its Na⁺/K⁺ balance and a milder response to Cl⁻ compared to the hybrid Hytech. Metabolic alterations were analyzed using advanced techniques, revealing specific responses in leaves and bulbs to Cl⁻ accumulation, with significant changes observed in organic acids involved in the TCA cycle, such as fumaric acid, and succinic acid, in both varieties. Additionally, there was a variety-specific increase in ethanolamine in Birnförmige and lysine in Hytech in response to Cl⁻ accumulation. Conclusion: This comprehensive study offers new insights into onion ion regulation and stress adaptation during the initial stages of salinity exposure, emphasizing the importance of considering both Na⁺ and Cl⁻ when assessing plant responses to salinity.

Browse

Browsing Sondersammlungen by Sustainable Development Goals "2"