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Environmental stresses are forcing breeders to produce new plant genotypes with higher resistance to stressors. Biochemical markers of stress tolerance would assist in the selection of tolerant cultivars on the early stages of plant development. The aim of these studies was to examine whether the concentration of micro and macroelements of embryos and/or endosperm could specify the wheat grains in terms of their tolerance to stress conditions. Two sensitive to drought (Radunia and Raweta), two tolerant (Nawra and Parabola) and one with intermediate tolerance (Manu) were chosen. After dividing embryos and endosperm, the microelements content (Mn, Fe, Cu, Zn and Mo) was analyzed by inductively coupled plasma mass spectrometry (ICP-MS) and macroelements (K, Ca, Mg, P and S) by inductively coupled plasma optical emission spectrometry (ICP-OES). Independent of genotype, the concentration of all elements was higher in embryos than in endosperm. In both embryos and endosperm of tolerant plants, higher content of microelements (except for Cu in embryos) was detected. The accumulation of macroelements was lower in embryos of tolerant plants (except for K), however, in the case of endosperm, higher amounts of these elements, were registered. In embryos of Manu genotype, the content of microelements was more alike to sensitive and macroelements to tolerant plants but in endosperm, the level of both micro- and macroelements was more similar to tolerant ones. It was concluded that mineral composition of wheat grains, especially those in embryos, could inform about possible resistance of genotypes to stress conditions.
The comparative responses of ten spring wheat cultivars to water stress were investigated. Wheat plants were cultured under hydroponics conditions (Hoagland nutrient) to the stage of three-leaf seedlings. Then, the water medium was supplemented with PEG (drought) or NaCl (salinity) to obtain a water status equal to -1.5 MPa. After a 2-day treatment, the changes in the following parameters were determined: fresh and dry weight, macroand microelement accumulation, membrane injury (electrolyte leakage, lipid peroxidation) and fatty acid content of the phospholipid fraction of plasmalemma (in comparison to plants not stressed, taken as a control). Generally, the plants were more significantly influenced by water stress stimulated by PEG than by NaCl treatment, as compared to the plants cultivated in the control media. The results of the decrease in water content in leaves and electrolyte leakage from cells corresponded well with the intensity of lipid peroxidation (determined by malondialdehyde—MDAcontent) and were chosen for the selection of investigated genotypes for tolerance to both stresses. The more tolerant genotypes exhibited the opposite changes in phospholipid fatty acid unsaturation for two applied stresses i.e. NaCl treatment caused a decrease in unsaturation whereas in PEG-treated plants an increase in unsaturation was observed. These changes were reversed for less tolerant plants, i.e. NaCl treatment influenced an increase in fatty acid unsaturation whereas in PEG-treated plants a decrease in unsaturation was measured. The ratio of U/S (unsaturated to saturated fatty acids) correlated with the total amount of accumulated macroelements. The content of Mg, Ca and S in leaves of plants undergoing both stress factors (NaCl and PEG) dropped whereas the K and P content increased in leaves of wheat seedlings cultured on media containing NaCl only. For microelements, a decrease in the accumulation of these nutrients was detected in all investigated seedlings. However, a greater reduction in the level of these elements occurred in seedlings grown on media with PEG in comparison to those grown on NaCl containing media.
 The procedure of restorative proctocolectomy is associated with a complete removal of the colon and slight reduction of ileum length, which together can lead to systemic shortages of trace elements. Inflammatory changes in the pouch mucosa may also have some impact. However, there is no data on trace elements in pouchitis. Therefore, in the present study we aimed to assess the effect of acute pouchitis on the status of selected trace elements in rats. Restorative proctocolectomy with the construction of intestinal J-pouch was performed in twenty-four Wistar rats. Three weeks after the surgery, pouchitis was induced. Eight untreated rats created the control group. Liver concentrations of selected micronutrients (Zn, Cu, Co, Mn, Se) were measured in both groups six weeks later, using inductively coupled plasma mass spectrometry. Liver concentrations of trace elements did not differ between the study and the control groups. However, copper, cobalt and selenium concentrations [μg/g] were statistically lower (p<0.02, p<0.05 and p<0.04, respectively) in rats with severe pouchitis (n=9) as compared with rats with mild pouchitis (n=7) [median (range): Cu - 7.05 (3.02-14.57) vs 10.47 (5.16-14.97); Co - 0.55 (0.37-0.96) vs 0.61 (0.52-0.86); Se - 1.17 (0.69-1.54) vs 1.18 (0.29-1.91)]. In conclusion, it seems that acute pouchitis can lead to a significant deficiency of trace elements.
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