UPTAKE AND DISTRIBUTION OF SELENIUM,NITROGEN AND SULFUR IN THREE BARLEY CULTIVARS SUBJECTED TO SELENIUM APPLICATIONS

Selenium (Se) is an essential micronutrient for humans and animals, and also affects plant metabolism. In this study, the effects of increasing doses of Se application on the uptake of selenium (Se), nitrogen (N), and sulfur (S) content of three barley cultivars were investigated. The analysis indicated that the Se contents were highest in root tissues, intermediate in grain, and lowest in stem tissues in all cultivars. Total Se accumulations (whole plant) were highest in ‘Bülbül 89’ (0.171 mg kg^?1), intermediate in ‘Çetin 2000’ (0.153 mg kg^?1), and lowest in ‘Tarm 92’ cultivars (0.124 mg kg^?1). In all cultivars, the increase in grain Se content resulted in a decrease in the grain N content. While ‘Bülbül 89’ can be suggested for biofortification purposes, less Se accumulating ‘Tarm 92’ cultivar can be suggested as a fodder in Se contaminated or high Se containing areas.     

Gastropod Assemblages as Indicators of Sediment Metal Contamination in Mangroves of Dumai, Sumatra, Indonesia

Impacts of heavy metal concentrations in sediments on the gastropod community structure were assessed in the coastal waters of Dumai, Sumatra, Indonesia. The objective of this study was to relate the levels of heavy metal pollution with the changes of gastropod community structure in the study area. Concentrations of Cd, Cu, Pb, Zn, Ni, and Fe in surface sediments collected from five sampling stations were analyzed and correlated with the abundance, species richness, and diversity of gastropod populations. Sediments at stations with more anthropogenic activities accumulated higher concentrations of heavy metals and consequently displayed lower abundances, lower species richness and diversity; while stations with lower heavy metal concentrations in sediments showed the opposite pattern in gastropod community metrics. The above findings are complemented by significant negative correlations p?<?0.05–0.01) between concentrations of Cd, Cu, Pb, Zn, and Ni in the sediments and gastropod abundance and species richness. Among the metals analyzed, Cu and Zn had strongest negative correlations with the gastropod diversity which suggests that these metals may be the most detrimental to gastropod populations in the mangrove area of Dumai coastal waters.     

An Alternative Sucker Management Method in Hazelnut: Application of Nitrogen Fertilizer Solution

The goal of this study was to determine the usability of nitrogen solution for hazelnut sucker management. This study was carried out from 2015 to 2016?at two hazelnut orchards; one established with the shrub (ocak) system in Atakum district and the other established with the multi-stemmed system in the Carsamba district, both in Samsun province. For sucker management, 21% ammonium sulphate (AS) and 26% calcium ammonium nitrate (CAN) fertilizer solutions were used. Doses of 0, 10, 15 and 20% of solutions for both fertilizers were tested. In the study, hazelnut suckers were removed by knife in July 2015 and March 2016. Nitrogen solution applications were started in September 2015 when suckers reached 20–30?cm length. In 2016 four applications were made from April to August. Fifteen days after the applications, the wilting ratio (starting from the tip) and newly emerged suckers per bush were determined. Nitrate, pH, and EC analyses were made with soil samples collected at the beginning of the experiment and compared to those taken 15 days after each application. As a result, a 10% dose of 21% ammonium sulphate fertilizer gave the best results for hazelnut sucker management. Nitrogen solution application should be started 1 to 1.5 months after removal of suckers by cutting with a knife. Suckers should be removed when they reach 15–20?cm length and before they are lignified. For effective sucker management, nitrogen solution application should be applied at least three times in a year.

     

Proximal soil sensing of soil texture and organic matter with a prototype portable mid‐infrared spectrometer

Recent advances in semiconductor technologies have given rise to the development of mid‐infrared (mid‐IR) spectrometers that are compact, relatively inexpensive, robust and suitable for in situ proximal soil sensing. The objectives of this research were to evaluate a prototype portable mid‐IR spectrometer for direct measurements of soil reflectance and to model the spectra to predict sand, clay and soil organic matter (SOM) contents under a range of field soil water conditions. Soil samples were collected from 23 locations at different depths in four agricultural fields to represent a range of soil textures, from sands to clay loams. The particle size distribution and SOM content of 48 soil samples were measured in the laboratory by conventional analytical methods. In addition to air‐dry soil, each sample was wetted with two different amounts of water before the spectroscopic measurements were made. The prototype spectrometer was used to measure reflectance (R) in the range between 1811 and 898 cm^?1 (approximately 5522 to 11 136 nm). The spectroscopic measurements were recorded randomly and in triplicate, resulting in a total of 432 reflectance spectra (48 samples × three soil water contents × three replicates). The spectra were transformed to log₁₀ (1/R) and mean centred for the multivariate statistical analyses. The 48 samples were split randomly into a calibration set (70%) and a validation set (30%). A partial least squares regression (PLSR) was used to develop spectroscopic calibrations to predict sand, clay and SOM contents. Results show that the portable spectrometer can be used with PLSR to predict clay and sand contents of either wet or dry soil samples with a root mean square error (RMSE) of around 10%. Predictions of SOM content resulted in RMSE values that ranged between 0.76 and 2.24%.     

Does dietary incorporation level of pea protein isolate influence the digestive system morphology in rainbow trout (Oncorhynchus mykiss)?

In the present study, fish meal (FM) was replaced by pea (Pisum sativum) protein (PP) in diet for Rainbow trout (Oncorhynchus mykiss) at levels of 0% (PP0), 25% (PP25), 50% (PP50), 75% (PP75) and 100% (PP100), and the effect of dietary PP level on the digestive system tracts and liver was investigated by micromorphological and histopathological evaluations. Morphometric measurements (mm 100g fish⁻¹) of the liver width and stomach length in rainbow trout were found to be significantly larger (p <0.05) in fish with high-level pea protein as the main protein source (PP75, PP100) compared to the low-level PP replacement group (PP25). No significant differences were found in morphometric measurements for pyloric caecum and intestines among treatment groups, whereas the number of the caecum of fish fed the PP25 diets significantly increased over the control (PP0) (p<0.05). In the histological examination of the liver, mild hydropic and vacuolar degeneration was observed in all experimental groups except PP0 and PP25. The measurements of pyloric caecum fold height, enterocyte length and width of tunica muscularis of the high-level pea protein groups of PP75 and PP100 were significantly higher (p <0.05) compared to the control group. In conclusion, 25% substitution of PP can be suggested for FM in trout diets, because the findings of the present study provided evidence that the digestive system improved by increasing the number of pyloric caecum at this replacement level.     

Effect of Drought Conditions at Boiling Stage on Some Chemical Constituents of Cotton Plant

The investigation was carried out to study the effect of drought conditions at boiling stage on chloroplast pigments and anthocyanin, in leaves, carbohydrate, phenols and total amino nitrogen content in leaves and roots, oil and protein contents in bolls of different ages. Seeds of cv. Giza 75 cotton were sown during 1987 and 1988 seasons in pots of 30 cm in diameter containing 11 kg of soil; after complete germination, thinning was carried out leaving one plant per pot. Plants were subjected to water stress conditions at boiling stage till the sign of wilting, while the control plants were irrigated regularly at this stage without allowing the plants to reach wilting stage and kept in turgid state. The results obtained can be summarized as follows:
1. Drought conditions decreased reducing sugar, nonreducing sugar, total soluble sugar and total amino nitrogen in leaves, while the reverse was true in roots.
2. Drought conditions reduced total and polyphenols content in leaves while it had no effect on phenols compounds in roots.
3. Drought conditions had no significant effect on pigments except total carotenoid in 1987 season.
4. Oil content in seeds of different boll ages decreased as a result of drought in both seasons.
5. In general drought condition increased protein content in 1987 season while the reverse was true in 1988 season.
6. Leaves and roots of wilted plants had more inhibitors as compared to turgid plants.     

Complementary Analytical Platforms of NMR Spectroscopy and LCMS Analysis in the Metabolite Profiling of Isochrysis galbana

This study was designed to profile the metabolites of Isochrysis galbana, an indigenous and less explored microalgae species. ¹H Nuclear Magnetic Resonance (NMR) spectroscopy and Liquid Chromatography-Mass Spectrometry (LCMS) were used to establish the metabolite profiles of five different extracts of this microalga, which are hexane (Hex), ethyl acetate (EtOAc), absolute ethanol (EtOH), EtOH:water 1:1 (AqE), and 100% water (Aq). Partial least square discriminant analysis (PLS–DA) of the generated profiles revealed that EtOAc and Aq extracts contain a diverse range of metabolites as compared to the other extracts with a total of twenty-one metabolites, comprising carotenoids, polyunsaturated fatty acids, and amino acids, that were putatively identified from the NMR spectra. Meanwhile, thirty-two metabolites were successfully annotated from the LCMS/MS data, ten of which (palmitic acid, oleic acid, α-linolenic acid, arachidic acid, cholesterol, DHA, DPA, fucoxanthin, astaxanthin, and pheophytin) were similar to those present in the NMR profile. Another eleven glycerophospholipids were discovered using MS/MS-based molecular network (MN) platform. The results of this study, besides providing a better understanding of I. galbana’s chemical make-up, will be of importance in exploring this species potential as a feed ingredient in the aquaculture industry.     

Yield,fruit quality and nutrient uptake of ‘Nabbut-Ahmar’ date palm grown in sandy loam soil as affected by NPK fertigation

A field experiment was conducted in 2011 and 2012 to study the effect of fertigation on yield, fruit quality and nutrient uptake of ‘Nabbut-Ahmar’ date palm cultivar grown in sandy loam soil. Three fertigation treatments were compared with traditional application. In traditional treatment (CT), the recommended dose [2300 g nitrogen (N), 1200 g phosphorus (P) and 1400 g/tree] was applied as a soil broadcast in three equal doses. The fertigation treatments, (T2), (T3) and (T4), represent all nitrogen, phosphorus and potassium (NPK) amounts of CT, 2/3 CT and 1/3 CT, respectively that were injected in twelve equal doses. The results showed that compared to CT, the fertigation treatments increased yield/palm by 41%, 31% and 18% for T3, T2 and T4, respectively. Beside the increase in yield, 33% and 66% of the applied fertilizers were saved by T3 and T4, respectively, compared with CT. Feritgation treatments had no negative impact on the overall fruit quality characteristics and even increased total soluble solids (TSS), soluble tannins and total phenols concentrations compared to the conventional fertilization. Availability of NPK increased by fertigation but without further increase in leaves and fruit. In conclusion applying 2/3 of the recommended dose of NPK fertilizers under dry land condition through fertigation maximize yield, quality and fertilizer use efficiency.     

Optimizing crop geometry for processing-grade tuber yield,quality and economics of potato in Grey Terrace Soil

Crop geometry has great influence on economically important characteristics such as total yield, processing-grade yield, tuber size distribution and tuber quality in Grey Terrace Soil. An experiment was conducted to develop a suitable crop geometry for the production of higher processing-grade yield and quality of potato tubers. The treatment consisted of three levels of inter-row spacing (60, 67.5 and 75 cm) and four levels of intra-row spacing (20, 25, 30 and 35 cm). Crop geometry significantly influenced growth, yield contributing characters, tuber size distribution and yield of potato. The highest chips, French fry grade tubers and total potato tuber yield were found in 67.5 cm × 25 cm crop geometry without affecting processing quality but all were in the highly acceptable range. Intra-row spacing of 25 cm produced the maximum processing quality tubers, closely followed by 30 cm. The highest gross and net returns with a benefit–cost ratio of 1.75 were recorded in 67.5 cm × 25 cm crop geometry. Therefore, the 67.5 cm × 25 cm crop geometry can be recommended for higher potato tuber yield and processing-grade tubers as well as higher economic return.     

Mechanical anisotropy in unidirectional glass fabric reinforced oligomeric siloxane modified polyester composites

In this study, the effect of incorporation of oligomeric siloxane into unsaturated polyester on mechanical behavior of unidirectional glass fiber/polyester composites has been investigated by means of tensile, flexural and short beam shear tests. The amount of oligomeric siloxane added into unsaturated polyester was in the range 1?C3 % by weight of the glass fabrics. Mechanical tests were conducted at different angles (0 °, 45 °, and 90 °) with respect to fiber direction. The higher siloxane content exhibited a tendency to have greater tensile, flexural and interlaminar shear strength values in machine direction, bias direction and cross direction. From Scanning electron microscopy images, the presence of polyester particles on the unidirectional glass fiber surface confirmed better adhesion.