‘Hass‘ and ‘Fuerte‘ avocado plants were grown under well-watered or waterlogged conditions. Results indicated significant effects on the majority of the allometric parameters in waterlogged plants, with ‘Fuerte‘ displaying a more pronounced growth inhibition. Waterlogged conditions caused a progressive and simultaneous decline in net photosynthetic rate and stomatal conductance, earlier in ‘Fuerte‘ than in ‘Hass‘. Maximal potential quantum yield of PSII was unaffected by the soil water regime and/or variety and leaf water potential values in waterlogged plants were not more negative compared with control plants. ‘Fuerte‘ waterlogged plants exhibited increased contents of thiobarbituric acid reactive substances, whereas oxidative injury was not detected in ‘Hass‘. Finally, none of the two cultivars displayed valuable antioxidant potential, as evidenced by the decreased activities of the antioxidant enzymes superoxide dismutase, guaiacol peroxidase, glutathione peroxidase, and ascorbate peroxidase., G. Doupis, N. Kavroulakis, G. Psarras, I. E. Papadakis., and Obsahuje seznam literatury
Alfalfa was grown in fíeld plots at the current CO2 concentratíon (350 pmol mol"' = C350) and at 350 pmol mol"' above the current concentratíon (= c^qq). Alfalfa and weed growth, and canopy water vapor (£) and carbon dioxide exchange (f) were determined for the first year. Alfalfa yield summed for the three harvests in the first year was greater for the C700 treatment in two of the years studied, but significantly less in a third year. Weed growth was unaffected. Survival of alfalfa plants was greater at Cypo for years in which there was substantíal mortality, even when yield was not increased by the C700 treatment. In špite of a persistent reduction in leaf conductance to water vapor (gj), total canopy conductance (g^) to water vapor did not differ between CO2 treatments when averaged over years, because of compensating changes in canopy leaf area. CO2 efílux (F) at night per unit of ground area was consistently less in the cjqq treatment, even when daytime CO2 uptake was higher. Hence the periodic harvesting of alfalfa crops does not necessarily allow elevated CO2 to cause persistent growth stimulatíon nor reduced water use.
The short notice evokes memories of an experimental observation published in 1920 by B. Gudden and R. W. Pohl, and since known as the Gudden-Pohl effect. The important role played by the effect during the development of quantum solid state physics between 1920 and 1950 is stressed. Other scientific activities of B. Gudden are briefly mentioned as well., Ivan Pelant., and Obsahuje bibliografii
Recently, there has been rapidly growing interest in the effects of the microbiota on host physiology and behaviour. Due to the nutritional value of bacteria, gut microflora may be particularly important in species that present nuptial gifts during courtship. Here, we explore whether the presence or absence of gut microbiota in males and females of the nuptial gift-giving species Drosophila subobscura (Collin, 1936) alters mating behaviour in terms of female preference, male investment, and female fecundity. We found that females that had been fed antibiotics, compared to females with intact gut bacteria, were more willing to mate with a male that had been fed normally. However female fecundity was higher when both males and females lacked gut bacteria compared to both individuals having a full complement of gut bacteria. This implies that the presence of the microbiota acts to reduce female fecundity in this species, and that male gut bacterial content influences female fecundity. Our results provide further evidence to the growing consensus that the microbiota of an individual may have important effects on both reproductive behaviour and physiology, and suggest that it may also contribute to the nutritional value of the nuptial gift in this system., Benjamin S. Walsh, Chloe Heys, Zenobia Lewis., and Obsahuje bibliografii
The aims of our study were to evaluate plasma levels of gut hormones in children with Type 1 diabetes mellitus (T1DM) in comparison with healthy contro ls and to corr elate plasma concentrations of gut hormones with blood biochemistry, markers of metabolic control and with anthropometric parameters. We measured postprandial levels of specific gut peptide hormones in T1DM children. Amylin, glucos e-dependent insulinotropic polypeptide (GIP), glucagon-like peptide 1 (GLP-1), ghrelin, leptin, pancreatic polypeptide (PP), and polypeptide YY (PYY) were assessed in 19 T1DM children and 21 healthy reference controls. Multiplex assay kit (LINCOplex®) was used for determination of the defined plasma hormone levels. T1DM subjects had significantly reduce d amylin (p<0.001) and ghrelin (p<0.05) levels, whereas GIP (p<0.05) was elevated when compared with healthy controls. Pl asma levels of other measured hormones did not differ statistically between the studied groups. Further analysis of T1DM patien ts demonstrated an association between body mass index and GL P-1 (r=0.4642; p<0.05), leptin (r=0.5151; p<0.05), and amylin (r=0.5193; p<0.05). Ghrelin levels positively correlated with serum HDL cholesterol (r=0.4760; p<0.05). An inverse co rrelation was demonstrated with triglycerides (TG) (r=-0. 5674; p<0.01), insulin dosage (r= -0.5366; p<0.05), and HbA1c% (r= -0.6864; p<0.01). Leptin was inversely correlated with TG (r= -0.6351; p<0.01). Stepwise regression analysis was performed to enlighten the predictive variables. Our study demonstrated an altered secretion pattern of gut peptide hormones in T1DM children. A close correlation was revealed between these peptides as well as with blood biochemistry, markers of me tabolic control and with anthropometric parameters. Further studies are essential to explore this issue in T1DM children., M. Huml ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy