Bulk element concentrations of whole grain and element spatial distributions at the tissue level were investigated in wheat (Triticum aestivum) grain grown in Zn-enriched soil. Inductively coupled plasma mass spectrometry and inductively coupled plasma optical emission spectrometry were used for bulk analysis, whereas micro-proton-induced X-ray emission was used to resolve the two-dimensional localization of the elements. Soil Zn application did not significantly affect the grain yield, but did significantly increase the grain Ca, Fe and Zn concentrations, and decrease the grain Na, P and Mo concentrations; bulk Mg, S, K, Mn, Cu, Cd and Pb concentrations remained unchanged. These changes observed in bulk element concentrations are the reflection of tissue-specific variations within the grain, revealing that Zn application to soil can lead to considerable alterations in the element distributions within the grain, which might ultimately influence the quality of the milling fractions. Spatially resolved investigations into the partitioning of the element concentrations identified the tissues with the highest element concentrations, which is of utmost importance for accurate prediction of element losses during the grain milling and polishing processes.
COBISS.SI-ID: 7578745
Understanding the uptake, accumulation and distribution of toxic elements in plants is crucial to the design of effective phytoremediation strategies, especially in the case of complex multi-element pollution. Using micro-proton induced X-ray emission, the spatial distribution of Na, Mg, Al, Si, P, S, Cl, K, Ca,Mn, Fe, Zn, As, Br, Rb, Sr, Cd and Pb have been quantitatively resolved in roots and rhizomes of an obligate wetland plant species, Typha latifolia, treated with a mixture of 100 M each of As, Cd and Pb, together.The highest concentrations of As, Cd and Pb were found in the roots of the T. latifolia, with tissue-specific distributions. The As was detected in the root rhizodermis, and in the rhizome the majority of the As was within the vascular tissues, which indicates the high mobility of As within T. latifolia. The Cd was detected in the root exodermis, and in the vascular bundle and epidermis of the rhizome. The highest Pb concen-trations were detected in the root rhizodermis and exodermis, and in the epidermis of the rhizome. Thesedata represent an essential step in the resolution of fundamental questions in plant ionomics.
COBISS.SI-ID: 2740303
Distinct metal distribution patterns within leaves of metal hyperaccumulating plants are repeatedly observed however, the presumable role of key structural biochemical molecules in determining and regulating their allocation remains largely unknown. We aimed to characterise in a spatially resolved manner the distribution of the main biochemical components in leaves of field-collected Cd/Znhyperaccumulating Noccaea praecox in order to relate them to metal distribution patterns at tissue level. The biomolecular composition of the leaves was spatially analysed using synchrotron radiation Fourier Transform Infrared (FTIR) and the distribution of Zn with synchrotron radiation Low-Energy X-Ray Fluorescence (LEXRF) microspectroscopy was determined on the same tissues of interest (epidermis, subepidermis, mesophyll). In epidermal cells high proportion of freecarboxyl, nitro and phosphate groups standing for pectin, nitroaromatics, phytic and other organic acids were found. Adjacent mesophyll cells had higher proportions of proteins, carbohydrates and cellulosic compounds. Pectin compounds were indicated as important components of Zn enriched epidermal cell walls. In addition, intense lignification of epidermal cell walls might limit leakage of the trapped metals back to the metabolically active and thus more sensitive mesophyll. Distribution of metal-binding compounds in particular cell types/tissues may therefore predispose metal distribution patterns and tolerance in leaves.
COBISS.SI-ID: 2802767