University of Hohenheim

About: University of Hohenheim is a education organization based out in Stuttgart, Germany. It is known for research contribution in the topics: Population & Soil water. The organization has 8585 authors who have published 16406 publications receiving 567377 citations.

Functional properties of anthocyanins and betalains in plants, food, and in human nutrition

Abstract: Anthocyanins and betalains play important roles both in plant physiology, visual attraction for pollinators and seed dispersers, but also in food mainly defining its aesthetic value. Since anthocyanin and betalain structures allow to predict only part of their appearance, additional chemical and anatomical functions are required to modulate the appearance of plants and coloured food. Physiological effects that the same pigments exert in plants are supposedly similar to those which they show in humans following ingestion of coloured food. Therefore, anthocyanins and betalains both in fresh and also processed fruit and vegetables serve two functions: They improve the overall appearance, but also contribute to consumers' health and well-being.

Determinants of Sustainability Reporting: A Review of Results, Trends, Theory, and Opportunities in an Expanding Field of Research

Abstract: Since the end of the 1990s, sustainability reporting has become an increasingly relevant topic in business and academia. However, literature is still limited in quantity and no major reviews of the latest developments have thus far been presented. This paper provides a review of 178 articles dating from 1999 to 2011 from journals related to business, management, and accounting. Our aim is to identify what determinants of sustainability reporting are examined in the literature and to identify (in)consistencies, gaps, and opportunities for future research. We specifically illuminate factors influencing the adoption, the extent, and the quality of reporting. Based on our findings we provide an otherwise often missing link to theory (especially legitimacy, stakeholder, signaling, and institutional theory). Finally, possible future research themes are discussed by illuminating gaps and underexposed themes in the area of regulation and governance as well as reporting quality and stakeholder perception.

Evidence for a specific uptake system for iron phytosiderophores in roots of grasses.

Abstract: Roots of grasses in response to iron deficiency markedly increase the release of chelating substances (;phytosiderophores') which are highly effective in solubilization of sparingly soluble inorganic Fe(III) compounds by formation of Fe(III)phytosiderophores. In barley (Hordeum vulgare L.), the rate of iron uptake from Fe(III)phytosiderophores is 100 to 1000 times faster than the rate from synthetic Fe chelates (e.g. Fe ethylenediaminetetraacetate) or microbial Fe siderophores (e.g. ferrichrome). Reduction of Fe(III) is not involved in the preferential iron uptake from Fe(III)phytosiderophores by barley. This is indicated by experiments with varied pH, addition of bicarbonate or of a strong chelator for Fe(II) (e.g. batho-phenanthrolinedisulfonate). The results indicate the existence of a specific uptake system for Fe(III)phytosiderophores in roots of barley and all other graminaceous species. In contrast to grasses, cucumber plants (Cucumis sativus L.) take up iron from Fe(III)phytosiderophores at rates similar to those from synthetic Fe chelates. Furthermore, under Fe deficiency in cucumber, increased rates of uptake of Fe(III)phytosiderophores are based on the same mechanism as for synthetic Fe chelates, namely enhanced Fe(III) reduction and chelate splitting. Two strategies are evident from the experiments for the acquisition of iron by plants under iron deficiency. Strategy I (in most nongraminaceous species) is characterized by an inducible plasma membrane-bound reductase and enhancement of H(+) release. Strategy II (in grasses) is characterized by enhanced release of phytosiderophores and by a highly specific uptake system for Fe(III)phytosiderophores. Strategy II seems to have several ecological advantages over Strategy I such as solubilization of sparingly soluble inorganic Fe(III) compounds in the rhizosphere, and less inhibition by high pH. The principal differences in the two strategies have to be taken into account in screening methods for resistance to ;lime chlorosis'.

Effects of anaerobic digestion on digestate nutrient availability and crop growth: A review

Abstract: Anaerobic digestion (AD) for biogas production leads to several changes in the composition of the resulting digestates compared to the original feedstock (ammonia content, pH, carbon to nitrogen ratio, etc.), which are relevant for the plant availability of macro- and micronutrients after field application. Increased NH4+-N content in digested slurries compared to undigested slurries does not guarantee improved uptake efficiency of slurry nitrogen and increased savings in fertilizer nitrogen. AD of crop residues and cover crops leads to an increase in the total amounts of mobile organic manures within the farming system, resulting in a higher nitrogen use efficiency and an increased scope for target-oriented nitrogen application in time and space, when needed by the crop, as an alternative to the site-bound soil incorporation as green manures. AD of dairy manure appears to reduce the fraction of immediate plant available phosphorus and micronutrients. This does, however, not affect short-term crop availability under field conditions. More studies are needed to improve current knowledge on sulfur losses during AD and fertilizer value of digestates.

Review: Factors affecting rhizosphere priming effects

Abstract: Living plants change the local environment in the rhizosphere and consequently affect the rate of soil organic matter (SOM) decomposition The rate may increase for 3- to 5-folds, or decrease by 10 % to 30 % by plant cultivation Such short-term changes of rate (intensity) of SOM decomposition are due to the priming effect In the presence of plants, a priming effect occurs in the direct vicinity of the living roots, and it is called rhizosphere priming effect (RPE) Plant-mediated and environmental factors, such as, plant species, development stage, soil organic matter content, photosynthesis intensity, and N fertilization which affect RPE are reviewed and discussed in this paper It was concluded that root growth dynamics and photosynthesis intensity are the most important plant-mediated factors affecting RPE Environmental factors such as amount of decomposable C in soil and N min content are responsible for the switch between following mechanisms of RPE: concurrence for N min between roots and microorganisms, microbial activation or preferential substrate utilization Succession of mechanisms of RPE along the growing root in accordance with the rhizodeposition types is suggested Different hypotheses for mechanisms of filling up the C amount loss by RPE are suggested The ecosystematic relevance of priming effects by rhizodeposition relates to the connection between exudation of organic substances by roots, the increase of microbial activity in the rbizosphere through utilization of additional easily available C sources, and the subsequent intensive microbial mobilization of nutrients from the soil organic matter