Effects of silicon on growth processes and adaptive potential of barley plants under optimal soil watering and flooding

Barley (Hordeum vulgare L.) was grown in pots with brown loess soil and highly soluble amorphous silicon dioxide as the source of monosilicic acid to examine its influence on plant growth and adaptive potential under optimal soil watering and flooding. The adaptive potential of plants was estimated by the concentration of the thiobarbituric acid reactive substances (TBARs) as well as superoxide dismutase (SOD), guaiacol peroxidase (GPX) and ascorbate peroxidase (AsP) activities. Application of amorphous silica to the soil increased the Si content in barley shoots and roots and stimulated their growth and biomass production under optimal soil watering. Soil flooding suppressed the growth both of the (−Si)- and (+Si)-plants. The intensity of oxidative destruction estimated by the concentration of TBARs was lower in the roots and leaves of the (+Si)-plants. Soil flooding induced SOD activity in the roots and in the leaves of the (−Si;+flooding) and (+Si;+flooding)-plants, but no significant differences were observed due to the Si treatment. GPX activity in the roots of (+Si)-plants was higher than in the (−Si)-ones under optimal soil watering, but under soil flooding no differences between (+Si)- and (−Si)-treatments were observed. AsP activity was not influenced by Si treatment neither under optimal soil watering nor under flooding. Thus, application of Si stimulates growth processes of barley shoots and roots under optimal soil watering and decreases intensity of oxidative destruction under soil flooding without significant changes in the activities of antioxidant enzymes.     

Seasonal Changes of Body Iron Status Determine Cadmium Accumulation in the Wild Bank Voles

The objective of this study was to examine relations between body iron (Fe) status and cadmium (Cd) accumulation in a small rodent, the bank vole, caught from the wild population in late autumn (November) and early spring (March). The concentrations of Fe in the liver, kidneys, and duodenum in the bank voles from the spring were only 30%, 60%, and 70%, respectively, of those found in the animals from the autumn. An analysis of hematocrit and hemoglobin content of blood showed no significant effect of the season, suggesting that the animals from the spring were not anemic. The exposure to dietary Cd (10 μg/g) for 7 days resulted in 70% higher accumulation of Cd in the liver and kidneys of the spring than autumn bank voles, and the concentration of Cd in the duodenum was 3.5 times higher in the spring animals, despite the fact that relative Cd intake was significantly higher in the autumn bank voles. The data indicate that seasonal changes of body Fe status occurring in the wild bank voles may influence tissue accumulation of Cd.     

Structure of the nectary in Chaenomeles japonica (Thunb.) Lindl. ex Spach. in different stages of flowering with focus on nectar secretion

Protoplasma - Chaenomeles japonica is an attractive ornamental shrub flowering in spring. It is also a valuable source of nectar and pollen for entomofauna. The study was carried out to investigate...     

Bayesian network model informs on the impact of biotic and abiotic factors on the population characteristics of an endangered plant species

Preservation of the endangered plant species requires knowledge of the impact of environmental factors on their populations. This study was undertaken to evaluate the potential of a Bayesian network (BN) model to analyze the impact of habitat conditions on the current characteristics of Pulsatilla patens (L.) Mill. population in NE Poland. The model was based on field data collected in 2011–2015 from 47 sites in the four largest forest complexes of NE Poland. The causal network between (1) the biotic and (2) abiotic factors as well as morphological-developmental features of individuals and demographic features of populations (20 attributes, 1573 records) was made using the Bayesian Search Algorithm in GeNIe 2.0. The results indicate that the greatest impact on the population features had the number of competing species in forest undergrowth and exposition of slopes. Diagnostic testing and sensitivity analysis revealed that these factors were the major variables determining the size of the population, developmental phase, and the size of individuals. Tenfold cross-validation revealed that this model was the most effective to analyze the impact of habitat conditions on the presence of generative shoots, developmental phase, and juvenile shoots. The optimal levels of factors following from the BN modeling of the impact of habitat conditions on the characteristics of the population will allow regular growth (size of individuals) and development (life cycle of individuals) of a given endangered species.     

Functional characterization of two melanocortin (MC) receptors in lamprey showing orthology to the MC1 and MC4 receptor subtypes

Background  

The melanocortin (MC) receptors have a key role in regulating body weight and pigmentation. They belong to the rhodopsin family of G protein-coupled receptors (GPCRs). The purpose of this study was to identify ancestral MC receptors in agnathan, river lamprey.     

Application of enzymatic apple pomace hydrolysate to production of 2,3-butanediol by alkaliphilic <Emphasis Type="Italic">Bacillus licheniformis</Emphasis> NCIMB 8059

2,3-Butanediol (2,3-BD) synthesis by a nonpathogenic bacterium Bacillus licheniformis NCIMB 8059 from enzymatic hydrolysate of depectinized apple pomace and its blend with glucose was studied. In shake flasks, the maximum diol concentration in fed-batch fermentations was 113 g/L (in 163 h, from the hydrolysate, feedings with glucose) while in batch processes it was around 27 g/L (in 32 h, from the hydrolysate and glucose blend). Fed-batch fermentations in the 0.75 and 30 L fermenters yielded 87.71 g/L 2,3-BD in 160 h, and 72.39 g/L 2,3-BD in 94 h, respectively (from the hydrolysate and glucose blend, feedings with glucose). The hydrolysate of apple pomace, which was for the first time used for microbial 2,3-BD production is not only a source of sugars but also essential minerals.     

Influence of tail versus cardiac sampling on blood glucose and lipid profiles in mice

Blood is collected during animal experimentation to measure haematological and metabolic parameters. It cannot be assumed that circulating blood has the same composition irrespective of its location, and indeed, differences in the composition of blood sampled from the arterial and venous compartments have been reported. Here we investigated whether blood collected by cardiac puncture (CP) versus that collected following removal of the distal 1 mm of the tail tip (TT) differs with respect to glucose and lipid profiles in male C57BL/6J mice at 4, 7, 20 and 28 weeks of age. Blood was first collected from the TT of unanaesthetized mice, which were then immediately anaesthetized using ketamine/xylazine, and a second blood sample was collected by CP. The CP glucose concentration was significantly higher than TT glucose by a positive bias averaging +80% (P < 0.01), irrespective of the age of the mice. Conversely, the concentrations of the CP lipids, including total cholesterol, high-density lipoprotein cholesterol and triglyceride were lower than TT lipids by a negative bias averaging -25% (P < 0.05). These observations highlight the difficulty in measuring and comparing metabolic parameters such as glucose and lipid between one blood compartment and another. They illustrate the need to standardize sampling sites, especially when repeated blood sampling is required.