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The objectives of this study were to determine if Selenium (Se) in the forms of Se (IV) and Se (VI) interact during uptake and assimilation by spinach plants (Spinacia oleracea L.), when they are applied together. That might affect selected physiological and morphological characteristics, and crop yield. Plants were foliar sprayed with different concentrations of Se as selenite and selenate, separately (each at the rate of 5, 10, 15 mg Se L-1), and simultaneously with selenite plus selenate (each at the rate of 5 mg Se L-1). Se accumulation in the spinach leaves was monitored, along with selected physiological and morphological characteristics. These foliar Se treatments had little or no effects on crop yield, content of photosynthetic pigments and UVA and UVB absorbing compounds, respiratory potential and plant biomass, and potential efficiency of photosystem II. This demonstrated the good conditions of the spinach plants under these foliar Se treatments. The spinach plants readily accumulated both forms of Se into the leaves. Direct comparison of their combined application (5+5 mg L-1) with their individual applications (10 mg L-1) showed that in the combined application, the plants accumulated Se more than in selenite alone treatment, but less Se than in the selenate alone treatment. Foliar spraying with all tested concentrations of selenite, selenate, or their combination ensured that spinach leaves were safe for use in human nutrition. According to our results, exogenous treatment with selenate in concentration of 15 mg L-1 was the most efficient treatment for production of Se enriched spinach. [ABSTRACT FROM AUTHOR]

Abstract: Q 0 and k 0 factors for 75Se were determined by means of the Cd-ratio and Cd-subtraction methods at the carousel facility of the TRIGA Mark II reactor. For their determination, certified Se standard solution (no. 70350, p.a., Merck, Darmstadt, Germany) containing 988±3mgkg−1 was added on cellulose in low amounts, to avoid self-shielding effects of the matrix element. The difference between Q 0 value obtained in this study differed from the literature value by −9.2%, while the k 0-factors for five recommended gamma lines differed from −3.3% for the 400.7keV line up to +13.1% for the 121.1keV line. Taking this into account, the differences in the Se content of a sample differed from −9.1% for the 121.1keV line up to +6.3% for the 400.7keV line. [Copyright &y& Elsevier]

Major and trace element contents in iron ore reference materials were investigated using k 0-instrumental neutron activation analysis ( k 0-INAA). To avoid iron interferences, radiochemical separation was developed ( k 0-RNAA). The determination of the investigated elements in the inorganic phase from hydrochloric acid solution was performed after radiochemical separation of iron by diisopropyl ether. It was found that after the Fe elimination, the limit of detection for some elements was much lower that enables their direct determination. The distribution of 39 elements (with intermediate/medium and long half-life radionuclides) after Fe removal was investigated. [ABSTRACT FROM AUTHOR]

Three groups of six hens each were fed for twelve days with diets containing 7.5, 15.0, and 30.0 mg arsenic per kg in the form of As2O3. A control group was included in the trial. The hens from each group were formed into three subgroups. The eggs of two hens, laid in three days, formed a composite sample. The As concentration in the egg whites and yolks was determined in duplicate by radiochemical neutron activation analysis. With increasing As concentration in the poultry feedstuff, its concentration in egg yolk and whitealso increased, but a plateau appears to be reached quite rapidly. The ratio between the As concentration in yolk and in white is nearly constant (1:3) for all three groups of hens, irrespective of the level of As in the feed. The concentration of arsenic in dry matter of whites was significantly higher than in the dry matter of yolks, while the concentrations of arsenic in fresh samples of yolks were higher in the comparison with fresh samples of whites, but the differences were not significant. [ABSTRACT FROM AUTHOR]

Abstract: Trace element contents in two copper minerals [brochantite [Cu4SO4(OH)6] and native Cu] using k 0-NAA were determined before and after quantitative removal of copper. The distribution of 44 elements in the studied minerals was investigated. An important advantage of the proposed method is the possibility to determine the content of several elements (Al, Dy, Mg, Mn and V) via their short-lived nuclides after the electrolytic removal of Cu due to the elimination of matrix interferences. [Copyright &y& Elsevier]

An investigation on the minerals and trace elements in foods widely consumed in Slovenia has been performed. Microwave-assisted digestion followed by flame and electrothermal atomic absorption spectrometry was used for the analysis. Validated analytical procedures were used and the accuracy was checked by using certified reference materials CRM 1570 a (spinach) and CRM 1573 a (tomato leaves). Good agreement was found between certified and determined data. Two individual samplings were preformed in 2002 and 2003. Data demonstrated that Zn, Cu, Cd, Pb, Cr and Ni concentrations in commonly consumed foods in Slovenia are comparable to the data reported for the European Union and other countries. The foodstuffs analysed were not contaminated with Cd, Pb or Ni. Higher Ni concentrations were found in the baby food "Čokolešnik" and were due to the cocoa content. Meat was rich in Zn (about 200 mg kg-1), while cabbage, wheat, potato, egg whites, instant milk, baby food and most fish contained less than 50 mg kg-1. The Cu concentrations in most of the samples were between 2 and 3 mg kg-1. In general, the Cr content in the foodstuffs was below 0.05 mg kg-1. Mussels, that accumulate elements from the marine environment, contained high concentrations of all the minerals and trace elements investigated. [ABSTRACT FROM AUTHOR]

The interactions between the uptake of selenium (as selenite and selenate) and iodine (as iodate and iodide) by red chicory ( Cichorium intybus L. var. foliosum Hegi) and their effects on selected morphological and physiological characteristics were investigated. Seedlings were transplanted to the field, and at the onset of head formation, the plants were foliar-sprayed with the following solutions: Milli-Q water (control), Se (IV), Se (VI), I (-I), I (V), Se (IV) + I (-I), Se (IV) + I (V), Se (VI) + I (-I) and Se (VI) + I (V). The different treatments had no significant effects on the yield (39.8-51.5 t ha -1 ) and mass (970-1200 g) of the chicory heads. The selenium content in Se-treated plants was up to 5.5-times greater than the control plants. The iodine content in the chicory leaves enriched with I was 3.5-times greater than the control plants. Iodide or iodate, applied together with selenite in the spray solution, increased the uptake of Se by chicory plants, while both forms of iodine, applied together with selenate, reduced the uptake of Se. Plants treated with I (V) had lower amounts of chlorophyll a and carotenoids than the control, while respiratory potential was higher than the control, which indicated the possible presence of stress in I (V)-treated plants. However, the potential photochemical efficiency of photosystem II was similar and close to the theoretical maximum (0.83) in the control and treated groups, which indicated that all of the plants were in good condition. Furthermore, the plant mass and yield were comparable in the control and treated groups. Molecular studies, like gene expression analysis, would represent a major upgrade of the present study by defining the mechanisms of Se and I uptake and their interactions and by enhancing the knowledge of the Se and I transporters.

The elements selenium (Se) and iodine (I) are both crucial for the normal functioning of the thyroid. Biofortification with these elements is particularly feasible in areas where they show a deficit. Iodine and selenium can have positive effects on different plants when applied at the correct concentrations. The effects of their simultaneous addition on plant physiology and biochemistry, as well as on seed germination and sprout biomass, were studied in pumpkin ( Cucurbita pepo L. ssp. pepo ). To study the effect of Se and I on sprouts, sprouts were grown from seeds soaked in solutions of different forms of Se, I and their combination in the growth chamber experiment. In the field experiment, pumpkins plants were foliarly treated with the same concentrations and forms of Se and I. The combination of Se and I treatments enhanced the germination of the soaked seeds, with no significant differences between Se and I treatments for sprout mass. The yield of pumpkins and seed production were unaffected by Se and I foliar application. The anthocyanin levels and respiratory potential measured via the electron transport system's activity showed different patterns according to treatments and plant parts (sprouts, leaves, seeds). The redistribution of Se and I from seeds to sprouts was significant. The accumulation of Se was higher in sprouts from the seeds treated with Se together with I, compared to sprouts from the seeds treated with Se alone. Interactions between Se and I were also noted in the seeds, which developed in the treated plants.

Kohlrabi (Brassica oleracea L. var. gongylodes L.) was biofortified with selenium (Se), as selenite and selenate, and iodine (I), as iodide and iodate, and their combinations through foliar spraying, to study absorption of these elements by the plants, separately and in combination. The effects on selected physiological and morphological traits and optical characteristics were monitored. Treatments with Se positively affected total chlorophylls and carotenoids, and leaf stomata dimensions. Addition of I decreased total chlorophylls and increased anthocyanins. In reflectance spectra of the leaves, specific colour regions differed significantly due to the different treatments. Reflectance in the UV correlated positively with Se and I contents of the leaves, which indicated lower demand for production of phenolic compounds. Differences in reflectance in UV part of the spectra could be a consequence of changes in the cuticle. The Se and I levels increased markedly in leaves and tubers, without loss of biomass or yield. Se had antagonistic effects on accumulation of I in leaves. The similar levels of Se and I in the leaves and tubers suggest that the transport of both elements in these plants occurs from the leaves to the tubers through the phloem. According to the Se and I contents in the kohlrabi tubers, biofortification with both elements simultaneously is feasible for human nutrition., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Masson SAS. All rights reserved.)

Background: The biofortification of crops can counteract human diseases, including selenium (Se) and iodine (I) deficiencies in the diet. Little is known about the effects of combinations of Se and I on microgreens and seeds, or on their accumulation in these tissues. The present study aimed to evaluate Se (SeO 3 2- , SeO 4 2- ) and I (I - , IO 3 - ) biofortification of common buckwheat microgreens and seeds with respect to the effects of the addition of Se, I and Se + I on yield and on physiological and biochemical characteristics., Results: In combination treatments, microgreens yield (600-800 g m -2 ) was 50-70% higher than for Se and I alone. The respiratory potential also increased by 60-120%. F v /F m was close to 0.8 in all samples. Se content [0.24 μg g -1 dry weight (DW)] was 50% higher for combination treatments than for Se and I alone. I content was highest for IO 3 - treatment (216 μg g -1 DW) and decreased in combination treatments with Se by 50%., Conclusion: Biofortification of buckwheat microgreens with Se and I should be performed with care because there are synergistic and antagonistic effects of these elements with respect to their accumulation. IO 3 - for the biofortification of microgreens should be kept low to prevent exceeding the recommended daily intake of I. © 2019 Society of Chemical Industry., (© 2019 Society of Chemical Industry.)