Grasslands may mitigate rising levels of the atmospheric %greenhouse gas% carbon dioxide by C sequestration in soil organic matter, depending on several environmental and management factors. The objective of this study was to examine the effects of long-term (19 years) different cutting frequencies (CFs), using equal amounts of mineral fertilisers (173 kg N, 40 kg P, and 150 kg K ha%1 year%1), on some sward and soil properties of previous extensively fertilised and utilised bio-diverse wet grassland. The impact of the study was directed towards the soil organic C and the apparent N budget. The CFs during the grassland experiment were cut at 2, 4, 6, 8,10, and 12-weekly intervals. CF significantly affected the sward and the soil characteristics of the grassland. The average number of plants per plot was high at medium CFs and low at low CFs. The above-ground biomass yield was high at medium and at low CFs, and its N content was high at medium and at high CFs. Soil organic C stocks (SOCS), soil total N stocks (STNS), and soil bulk density showed significant interactive responses to CFs % soil depths (0 cm, 10%20 cm). Due to high amounts of symbiotically fixed N by legumes at higher CFs, the average above-ground biomass yields contained more N than was added with fertilizers. In contrast to the second soil layer, the first soil layer in those treatments was rich in SOCS and STNS. In treatment of 8-weekly intervals between cuts, the balance between N inputs and N taken-up by plants was closest to zero. Especially in those cases of low CFs (10 and 12-weekly intervals between cuts), the apparent N budget showed that N added with fertilisers was not fully removed from the system regarding above-ground biomass yields. Due to high SOCS and STNS in both soil layers it can be assumed that N surplus had been partly built into the soil organic matter. However, a part of N was uncontrollably lost from the soil%plant system. The obtained results highlight the complexity of the problem of C sequestration. In reality none of the treatments at the end of the experiment displayed everything, namely, high SOCS in both layers of the soil, low uncontrolled outputs of N from the system, high plant diversity and high yields of above-ground plant biomass.
COBISS.SI-ID: 3953964
The aim of this work was to examine the compatibility of different rootstocks with various wine grape varieties. In the first trial, Vitis vinifera L. cvs. Furmint, Regent, Riesling, Sauvignon Blanc, and Welschriesling were grafted onto Börner, 5BB and SO4 rootstocks. In the second trial Welschriesling was grafted on 12 rootstocks. Their growth during the first year in the vineyard was measured. As an index of compatibility, the percentage of first grade grafted vines as well as dry weight of mature shoots (canes) and roots was determined. After the grafts went through the first phase of healing often called callusing (2%3 weeks of moist warm conditions), the differences in callus formation were greater between years than among rootstocks, which were the most obvious with Furmint as a scion. No good callus formation occurred when cane (rootstock, scion) maturity is not adequate. Such was the case in 2005, there were 24% fewer grafts with fully developed callus than those in 2006. The dry weight of roots was higher on 5BB than on Börner and SO4. Börner rootstock had fewer roots, and the roots were thinner. Welschriesling had good compatibility with all rootstocks (the average grafts success was 67%), but that of 5BB, G251, and G103 (above 80%) was greater than the average. The G103 rootstock had the highest dry weight of roots. Shoot growth in vineyards was above the average with 5BB, SO4, Binova, Börner, and M V rootstocks. All Georgikon rootstocks had a lower cane dry weight per vine than the others.
COBISS.SI-ID: 3832620
Environmental protection and human health have recently become important factors when selecting food production systems. The wide usages of pesticides and synthetic fertilisers in conventional production cause environmental pollution and degradation. Cover crops can reduce the use of external inputs such as pesticides and fertilisers and can at the same time suppress weeds as well as improve and maintain soil fertility. Cover crops can also modify the microclimate which affects pest populations and diseases. The cover crops are usually terminated before the planting of the main crops, but some management practices use cover crops simultaneously with the main crop to, provide living mulch. Determining, cover crop species and management practices is based on the needs and goals of sustainable production. The summarised studies show that further research is needed for best practices of vegetable production especially using living mulches and roller crimper for termining cover crops before planting vegetables.
COBISS.SI-ID: 4060716
In the nervous system, NMDA receptors (NMDARs) participate in neurotransmission and modulate the viability of neurons. In contrast, little is known about the role of NMDARs in pancreatic islets and the insulin-secreting beta cells whose functional impairment contributes to diabetes mellitus. Here we found that inhibition of NMDARs in mouse and human islets enhanced their glucose-stimulated insulin secretion (GSIS) and survival of islet cells. Further, NMDAR inhibition prolonged the amount of time that glucose-stimulated beta cells spent in a depolarized state with high cytosolic Ca2+ concentrations. We also noticed that, in vivo, the NMDAR antagonist dextromethorphan (DXM) enhanced glucose tolerance in mice, and that in vitro dextrorphan, the main metabolite of DXM, amplified the stimulatory effect of exendin-4 on GSIS. In a mouse model of type 2 diabetes mellitus (T2DM), long-term treatment with DXM improved islet insulin content, islet cell mass and blood glucose control. Further, in a small clinical trial we found that individuals with T2DM treated with DXM showed enhanced serum insulin concentrations and glucose tolerance. Our data highlight the possibility that antagonists of NMDARs may provide a useful adjunct treatment for diabetes.
COBISS.SI-ID: 512478264
The effect of adding hydrolysable tannins to the diet of fattening boars was studied. Performance, reproductive organ weights, salivary gland morphology, boar taint compounds and skatole metabolism were evaluated. At 123 days of age and 52 ± 6 kg liveweight, 24 Landrace × Large White boars were assigned within a litter to four treatment groups: control (T0 fed mixture with 13.2 MJ/kg, 17.5% crude proteins) and three experimental diets for which the T0 diet was supplemented with 1%, 2% and 3% of hydrolysable tannin-rich extract (T1, T2 and T3, respectively). Pigs were kept individually with ad libitum access to feed and water and slaughtered at 193 days of age and 122 ± 10 kg liveweight. Adding hydrolysable tannins to the diet had no negative effect on growth performance at 1% and 2%, whereas the 3% inclusion reduced feed intake and resulted in an adaptive response of the salivary glands (particularly parotid gland hypertrophy). Relative to T0, fat tissue skatole concentration was increased in the T1 group, but was similar in T2 and T3. Across treatments tissue skatole concentrations were proportional to the activity of hepatic CYP450. The results indicate the potential of tannin supplementation to reduce boar taint although further investigations are needed in order to establishing optimal dosage.
COBISS.SI-ID: 4650600