Search results for " Nitrogen"

KOSMOS 2017 Peru Side Experiment: nutrients, phytoplankton abundances, enzyme rates, photophysiology

2022

This data was collected during an short-term incubation experiment in March 2017 that investigated the response of a surface plankton community to upwelling. This experiment was carried in the framework of the SFB754-funded KOSMOS mesocosm study that took place in La Punta, Callao, Peru between February-April 2017. A total of six different treatments were used to disentangle chemical and biological characteristics of deep water that influence surface plankton blooms: 2 different deep water sources with different nutrient concentrations; 3 treatments to distinguish the effects of inorganic nutrients, organic nutrients and deep water microbial populations. Measured variables include inorganic…

Oxidative and nitrosative stress in the metastatic microenvironment.

2010

Metastases that are resistant to conventional therapies are the main cause of most cancer-related deaths in humans. Tumor cell heterogeneity, which associates with genomic and phenotypic instability, represents a major problem for cancer therapy. Additional factors, such as the attack of immune cells or organ-specific microenvironments, also influence metastatic cell behavior and the response to therapy. Interaction of cancer and endothelial cells in capillary beds, involving mechanical contact and transient adhesion, is a critical step in the initiation of metastasis. This interaction initiates a cascade of activation pathways that involves cytokines, growth factors, bioactive lipids and r…

Rapid change in forms of inorganic nitrogen in soil and moderate weed invasion following translocation of wet meadows to reclaimed post‐industrial la…

2019

Anthropogenic expansion and loss of natural environments calls for the more sustainable use of resources, including land. To combine the conservation of highly valuable meadow habitat with reclamation of post‐industrial land, 1.3 ha of turf were translocated from an urban area to basins constructed near an abandoned quarry. In contrast to the usual method of choosing similar habitats as salvage sites, the selected quarry possessed different environmental properties to the meadows, challenging their acclimatisation. To evaluate the project, we monitored three meadows (Molinion caeruleae alliance) for three seasons: immediately before the transfer and for 2 years afterwards. We recorded veget…

Cryopreservation of Hazelnut (Corylus avellana L.) Axillary Buds from In Vitro Shoots Using the Droplet Vitrification Method

2021

Cryopreservation by droplet vitrification was applied to hazelnut (Corylus avellana L.). axillary buds of the Italian cultivated variety Tonda Gentile Romana, which were collected from in vitro growing shoots, immersed in ice cooled PVS2 or PVS3 for 60 or 90 min, then transferred to a droplet of vitrification solution, placed on a strip of aluminium foil, and plunged into liquid nitrogen (LN). Additionally, the effect on the recovery of the mother plant after cryopreservation was evaluated, following a cold pre-treatment at 4 °C for 3 months. The highest regrowth percentage (56.7%) was obtained after applying PVS3 for 60 min, while the application of PVS2 for the same amount of time reduced…

Role of rotation and nitrogen fertilization on the productive and qualitative response of a barley (Hordeum vulgare L.)

2009

Nitrogen Availability Drives Mycorrhizal Effects on Wheat Growth, Nitrogen Uptake and Recovery under Salt Stress

2022

The arbuscular mycorrhizal (AM) symbiosis is generally considered effective in improving salt tolerance in plants; however, the advantages it offers can vary greatly depending on the context in which it occurs; furthermore, the mechanisms underlying these responses are still unclear. A study was conducted to investigate the role of nitrogen (N) availability on the effectiveness of AM symbiosis in durum wheat (Triticum durum Desf.) plants grown under salt stress. Plants were grown in pots in the absence or in presence of salt stress (soil electrical conductivity of 1.50 and 13.00 dS m−1, respectively), with or without AM fungi inoculation (Rhizophagus irregularis and Funneliformis mosseae), …

Labile nitrogen, carbon, and phosphorus pools and nitrogen mineralization and immobilization rates at low temperatures in seasonally snow-covered soi…

2006

Surface mineral horizons from four ecosystems sampled in the northwestern Italian Alps were incubated at −3 and +3°C to simulate subnivial and early thaw period temperatures for a seasonally snow-covered area. The soil profiles at these sites represent extreme examples of management, grazed meadow (site M) and extensive grazing beneath larch (site L) or naturally disturbed by avalanche and colonized by alder (site A) and the expected forest climax vegetation beneath fir (site F). Changes in labile pools of nitrogen (N) and phosphorus (P) were active at all sites at both temperatures during 14 days of laboratory incubation. Ammonium was the dominant inorganic form of total dissolved N (TDN),…

The Lotus japonicus ROP3 Is Involved in the Establishment of the Nitrogen-Fixing Symbiosis but Not of the Arbuscular Mycorrhizal Symbiosis

2021

Legumes form root mutualistic symbioses with some soil microbes promoting their growth, rhizobia, and arbuscular mycorrhizal fungi (AMF). A conserved set of plant proteins rules the transduction of symbiotic signals from rhizobia and AMF in a so-called common symbiotic signaling pathway (CSSP). Despite considerable efforts and advances over the past 20 years, there are still key elements to be discovered about the establishment of these root symbioses. Rhizobia and AMF root colonization are possible after a deep cell reorganization. In the interaction between the model legume Lotus japonicus and Mesorhizobium loti, this reorganization has been shown to be dependent on a SCAR/Wave-like signa…

Benthic foodweb structure in a large shallow lake studied by stable isotope analysis

2014

The benthic foodweb structure of Lake Võrtsjärv, a large (270 km2), shallow, and turbid Estonian lake, was evaluated based on C and N stable-isotope signatures (δ13C, δ15N). Variation in δ13C between sampling sites was not related to site proximity to the littoral zone or the more vegetated southern part of the lake, but rather appeared to be influenced by in-situ site peculiarities. δ13C was stable temporally and between functional feeding groups, a result implying that the whole benthic food web of the lake relies largely on the same C source admixture, essentially particulate organic matter (POM). Thus, the foodweb composition of Lake Võrtsjärv is remarkably homogeneous given the lake’s …