Silicon improves salinity tolerance in wheat plants

Durum wheat (Triticum durum cv. Gediz-75) and bread wheat (Triticum aestivum cv. Izmir-85) were grown in a complete nutrient solution in a growth room to investigate effect of silicone supplied to the nutrient solution on plants grown at salt stress. The experiment was a 2 × 2 factorial arrangement with two levels of NaCl in nutrient solution, 0 and 100 mM, and two levels of silicone (Si) in nutrient solution, 0.25 and 0.50 mM, as Na₂SiO₃. The plants grown at 100 mM NaCl produced less dry matter and chlorophyll content than those without NaCl. Supplementary Si at both 0.25 and 0.5 mM ameliorated the negative effects of salinity on plant dry matter and chlorophyll content. Membrane permeability and proline content in leaves increased with addition of 100 mM NaCl and these increases were decreased with Si treatments. Sodium (Na) concentration in plant tissues increased in both leaves and roots of plants in the high NaCl treatment and Si treatments lowered significantly the concentrations of Na in both leaves and roots. Bread wheat was more tolerant to salinity than durum wheat. The accumulation of Na in roots indicates a possible mechanism whereby bread wheat copes with salinity in the rooting medium and/or may indicate the existence of an inhibition mechanism of Na transport to leaves. Concentrations of both Ca and K were lower in the plants grown at high NaCl than in those in the control treatment and these two element concentrations were increased by Si treatments in both shoots and roots but remained lower than control values in most cases.     

Yeast Flora during the Fermentation of Wines Made from Vitis viniferaL. cv. Emir and Kalecik Karasi Grown in Anatolia

Summary A study was conducted of the growth of Saccharomyces (S.) and non-Saccharomyces populations during alcoholic fermentation of Emir and Kalecik karasi grape varieties in the 1998 and 1999 vintages. Kloeckera (Kl.) apiculata, Kluyveromyces (K.) thermotolerans, S. cerevisiae and Candida (C.) pulcherrima were the dominant yeasts in fermentation of the 1998 vintage in Emir must. Kl. apiculata and K. thermotolerans proliferated at the beginning of the fermentation. The number of these yeasts eventually decreased when S. cerevisiae appeared as the dominant yeast on day four. But they remained until the end of the fermentation. Kl. apiculata, C. dattilla, C. pulcherrima, C. krusei and S. cerevisiae were found during the fermentation of the 1999 vintage Emir must. The count of S. cerevisiae was very high in the juice, but after skin fermentation and cold treatment, it disappeared and could not be isolated until day six of the fermentation. Kl. apiculata and C. dattilla were the dominant yeasts until S. cerevisiae started proliferation after the middle of the fermentation. Kl. apiculata, Metschnikowia (M.) pulcherrima, S. cerevisiae, C. holmii, C. valida, C. guillermondii and Candida sp. were isolated during the fermentation of Kalecik karasi must in 1998. Kl. apiculata, C. pulcherrima, S. cerevisiae, C. holmii and C. valida were identified in fermentation of must in the 1999 vintage. An erratum to this article is available at .     

Examining Microscopic Organisms under Augmented Reality Microscope: A 5E Learning Model Lesson

As a fundamental strategy for all science curriculum, inquiry is of prime importance. In order to facilitate inquiry during science education in middle school, 5E learning model was applied in this study. Following 5E learning model during a lesson, students can engage in a topic after being served to mitigate cognitive disequilibrium or familiar with daily-life examples such as yoghurt fermentation, oven spring, etc. explore the topic making an observation or testing hypothesis, explain and relate their experiences scientifically, extend or elaborate their knowledge and then being evaluated. This study introduces a sample 5E learning model for middle school students at the ages of 10–12 in science laboratory with an augmented reality microscope MicrosAR to examine microscopic organisms based on inquiry-based learning.     

Device Characteristics of an 11.4% CZTSe Solar Cell Fabricated from Sputtered Precursors

Kesterite is an attractive material for absorber layers in thin film photovoltaics. Solar cells based on kesterite have shown a substantial progress over the last decade; nevertheless, further improvements in device efficiency are pending due to the open‐circuit voltage (V_oc) deficit (i.e., difference between the maximum V _oc that can be achieved according to Shockley–Queisser limit and actual V _oc from the device). In this study, the optoelectronic properties of the author's internal record Cu₂ZnSnSe₄ solar cell, which shows a power conversion efficiency of 11.4%, are presented. The device measurements reveal a V_oc deficit of 337 mV, which is one of the lowest V _oc deficits in the literature. Moreover, an unusual behavior for kesterite is observed: (i) photon energy of the photoluminescence emission and (ii) the extrapolated V _oc for 0 K are both matching the band gap region of the absorber. These results indicate a significant improvement in the recombination characteristics and absorber quality in comparison to other kesterite devices in literature.     

Serum and hair zinc levels in epileptic children taking valproic acid

This study was performed to investigate the serum and hair zinc levels in patients having epilepsy diagnoses who were intended to be put on valproic acid (VA) monotherapy and had never ingested antiepileptics before. A total of 16 patients having normal growth, development, and nutrition was selected as Group 1, and Group 2 was made up of 10 patients who had received VA monotherapy for 2 yrs or more and had normal growth, development, and nutrition characteristics. A control group (Group 3) was formed of 15 subjects who applied to the hospital for upper respiratory tract disorders. Serum and hair samples were taken for zinc assays from the Group 1 patients on the d 0, 15, 30, 45, 60, 75, and 180. Groups 2 and 3 were sampled only once, and zinc levels were determined. We found that both serum and hair zinc levels in Group 1 were higher than those of Group 2 and control group before the beginning of VA therapy, but they returned to normal during VA treatment. There was no zinc deficiency, and zinc replacement treatment may therefore be considered as unnecessary.     

Description of the immature stages of two Mononychus species (Coleoptera: Curculionidae: Ceutorhynchinae) and a study of the host preferences of M. punctumalbum for Iris species in central Europe

Last larval instars and pupae of Mononychus punctumalbum (Herbst, 1784) and Mononychus schoenherri Kolenati, 1859 (Curculionidae, Ceutorhynchinae) are described in detail for the first time. No immatures of other species of this genus had previously been described. The immatures of Mononychus were compared with available data on immatures of all genera in the subfamily Ceutorhynchinae. Both the larvae and pupae of the two Mononychus species are very distinctive, having distinct characters from other genera in the subfamily Ceutorhynchinae. New bionomic data for M. punctumalbum concerning its host preferences for Iris species in central Europe can be used to verify literature data indicating the important role of the iris weevil in the dramatic decline in the plant's abundance in natural habitats as well as in gardens and other anthropogenic associations.     

Prediction of enzyme function based on 3D templates of evolutionarily important amino acids

Background  

Structural genomics projects such as the Protein Structure Initiative (PSI) yield many new structures, but often these have no known molecular functions. One approach to recover this information is to use 3D templates – structure-function motifs that consist of a few functionally critical amino acids and may suggest functional similarity when geometrically matched to other structures. Since experimentally determined functional sites are not common enough to define 3D templates on a large scale, this work tests a computational strategy to select relevant residues for 3D templates.     

Grain zinc, iron and protein concentrations and zinc-efficiency in wild emmer wheat under contrasting irrigation regimes

Micronutrient malnutrition, and particularly deficiency in zinc (Zn) and iron (Fe), afflicts over three billion people worldwide, and nearly half of the world’s cereal-growing area is affected by soil Zn deficiency. Wild emmer wheat [Triticum turgidum ssp. dicoccoides (Körn.) Thell.], the progenitor of domesticated durum wheat and bread wheat, offers a valuable source of economically important genetic diversity including grain mineral concentrations. Twenty two wild emmer wheat accessions, representing a wide range of drought resistance capacity, as well as two durum wheat cultivars were examined under two contrasting irrigation regimes (well-watered control and water-limited), for grain yield, total biomass production and grain Zn, Fe and protein concentrations. The wild emmer accessions exhibited high genetic diversity for yield and grain Zn, Fe and protein concentrations under both irrigation regimes, with a considerable potential for improvement of the cultivated wheat. Grain Zn, Fe and protein concentrations were positively correlated with one another. Although irrigation regime significantly affected ranking of genotypes, a few wild emmer accessions were identified for their advantage over durum wheat, having consistently higher grain Zn (e.g., 125 mg kg^?1), Fe (85 mg kg^?1) and protein (250 g kg^?1) concentrations and high yield capacity. Plants grown from seeds originated from both irrigation regimes were also examined for Zn efficiency (Zn deficiency tolerance) on a Zn-deficient calcareous soil. Zinc efficiency, expressed as the ratio of shoot dry matter production under Zn deficiency to Zn fertilization, showed large genetic variation among the genotypes tested. The source of seeds from maternal plants grown under both irrigation regimes had very little effect on Zn efficiency. Several wild emmer accessions revealed combination of high Zn efficiency and drought stress resistance. The results indicate high genetic potential of wild emmer wheat to improve grain Zn, Fe and protein concentrations, Zn deficiency tolerance and drought resistance in cultivated wheat.