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Mihaela Monica Aldea,Venera Mihaela Stroe,Radu L?c?tu?u
Present Environment and Sustainable Development , 2011,
Abstract: The organic compounds of selenium and selenates are the most available for uptake by plants. Their presence in soil over a certain level (seleniferous soil)can lead to increase of selenium content in plants who grow on respective soils, and in conclusion if we are to consume these plants, toxicological phenomena can appear – acute or chronic at human body and animals (selenosis). This paper is focused on the South-Eastern part of the Romanian Plain, Central and South Dobrogea, where a study was done regarding low level of selenium in plants, these areas being characterized by a natural handicap - selenium deficiency. For this purpose, data regarding selenium total content in plant (wheat), determined through investigations, chemical methods and analytic techniques, are presented. Analytical data were statistically analyzed, determining the parameters of the clustering center (xmed, xg, Me, Mo) and the scattering parameter values (xmin, xmax, cv, σ)
Determining Social Economical and Farming Characteristics of Wheat Farmers Regarding Adoption of Low Input Sustainable Agriculture (LISA) (in Khuzestan Province)  [cached]
A. R. Ommani,M. Chizari
Journal of Science and Technology of Agriculture and Natural Resources , 2006,
Abstract: The main objective of this article is to present the results of a study done about the social, economical, and farming characteristics of wheat farmers in Khuzestan province of Iran regarding adoption of low input sustainable agriculture (LISA). LISA practices have tended to reduce the use of fertilizer pesticides, and maximal tillage, but, rely more on crop rotation, crop residues, animal manure, green manure, leguminous, appropriate mechanical cultivation or minimal tillage to optimize soil and natural pest control activity. The research design was a descriptive and correlation surveying method. Wheat farmers in Ahvaz, Behbahan, and Dezful township of Iran who cultivated wheat by the use of irrigation in the year of 1379-80 were the target population for this study. A random sample of wheat farmers selected from three randomly selected township of Ahvaz, Behbahan, and Dezful township (N = 5529 , n = 359 ). The main results of the study indicated that correlation of level of education, wheat land, ownership land , income, social participation, social status, social norm, technical knowledge, LISA knowledge, with adoption LISA practices were significantly positive and the correlation of age, experience in agriculture, distance between farm and service centers with adoption LISA practices were significantly negative.
Selenium (Se) Regulates Seedling Growth in Wheat under Drought Stress  [PDF]
Fahim Nawaz,Muhammad Yasin Ashraf,Rashid Ahmad,Ejaz Ahmad Waraich,Rana Nauman Shabbir
Advances in Chemistry , 2014, DOI: 10.1155/2014/143567
Abstract: Selenium (Se) is an essential micronutrient with a range of physiological and antioxidative properties. Reports regarding effect of Se application on plants growth and development are not consistent. The identification of effective Se dose and application method is crucial for better understanding of Se translocation within crop plants under drought stress. The present study aimed at investigating the role of Se supplementation in improving the drought tolerance potential of wheat at early growth stages. Two wheat genotypes (Kohistan-97 and Pasban-90) were grown in plastic pots (8 × 12?cm) in green/wire-house experiments. Results demonstrated that the growth and biomass of seedlings increased at high Se foliar concentrations and decreased at low and high Se fertigation levels. The seedlings exhibited the highest values for plant height stress tolerance index (PHSI), root length stress tolerance index (RLSI), dry matter stress tolerance index (DMSI), and fresh matter stress tolerance indices (FMSI) at Se fertigation level of 7.35?μM, whereas Se foliar treatment of 7.06?μM resulted in maximum values for these indices. The seedlings foliarly sprayed with Se maintained higher DMSI and FMSI than those fertigated with Se which suggests that Se foliar spray is more effective than Se fertigation for improving drought tolerance. 1. Introduction Drought stress has emerged as the single most critical threat to world food security. It seriously limits agricultural productivity, especially in areas where rainfall is limiting or unreliable, so improving yield under limited water conditions has become a crucial target for arid and semiarid regions of the world [1–3]. Exposure to drought stress poses serious challenges for the survival of plants, because it results in impaired germination and seedling growth [4] and affects many growth variables of the plant ?[5, 6], thus reducing fitness and harvestable yield of plants [3]. The physiological and antioxidant properties of selenium (Se) have increased the curiosity of many biologists in recent past. Although it does not take part in various vital metabolic processes in plants, it may help to reduce the damage under physiological stresses [7, 8]. Recently, Se has been reported to counteract the detrimental effects of various environmental stresses such as heavy metals [9], UV-B [10, 11], excess water [12], salt [13], cold [14], high temperature [15], senescence [16], and desiccation [17]. However, reports on the role of Se in plants under water stress conditions are scanty. It may regulate water status [18] and increase
Determining Effect of Lime and Urea Treatment on Crude and Digestible Nutrient Content of Wheat Straw
Abdullah Can,Nihat Denek,Ahin Tufenk,Ayfer Bozukrt
Journal of Animal and Veterinary Advances , 2012,
Abstract: This study was conducted to determine the effects of lime and urea treatment on crude and digestible nutrient content of wheat straw. Experimental diets consist of 80 percent straw treated with combination of 2 or 4 % urea and 2.5 or 5% lime or untreated straw and 20% ground wheat grain. An apparent digestion trial was conducted according to 5 x 5 Latin square design using 5 Awassi ram lambs, 5 diets, and 5 periods. Diets containing treated straw had lower organic matter (P <0 .01), higher crude protein content ( P <0 .05) than dirts with untreated straw . All the diets had the similar crude fat and fiber content (P > 0.05). Urea and lime treated straw containing diets had better organic matter, crude fiber, and crude protein digestibility than untreated straw containing diets (P < 0.05) . Treating wheat straw with lime and urea also improved dry matter intake and organic matter intakes and decreased diet consumption and chewing lenght ( P < 0.05).
Selenium Content in Seafood in Japan  [PDF]
Yumiko Yamashita,Michiaki Yamashita,Haruka Iida
Nutrients , 2013, DOI: 10.3390/nu5020388
Abstract: Selenium is an essential micronutrient for humans, and seafood is one of the major selenium sources, as well as red meat, grains, eggs, chicken, liver and garlic. A substantial proportion of the total amount of selenium is present as selenium containing imidazole compound, selenoneine, in the muscles of ocean fish. In order to characterize the selenium content in seafood, the total selenium levels were measured in the edible portions of commercially important fish and shellfish species. Among the tested edible portions, alfonsino muscle had the highest selenium levels (concentration of 1.27 mg/kg tissue). High levels of selenium (1.20–1.07 mg/kg) were also found in the salted ovary products of mullet and Pacific herring. In other fish muscles, the selenium levels ranged between 0.12 and 0.77 mg/kg tissue. The selenium levels were closely correlated with the mercury levels in the white and red muscles in alfonsino. The selenium content in spleen, blood, hepatopancreas, heart, red muscle, white muscle, brain, ovary and testis ranged between 1.10 and 24.8 mg/kg tissue in alfonsino.
Determining fertilizer quantities required for wheat  [PDF]
Kresovi? Mirjana M.,Li?ina V.
Journal of Agricultural Sciences , 2003, DOI: 10.2298/jas0301039k
Abstract: In this experiment we used brown forest soil that has been used in long-term experiments, for 30 years, with increasing doses of introduced nitrogen fertilizer in variants. In order to determine the quantities of nitrogen fertilizer required for wheat, a calculation model has been applied. This calculation requires not only a reliable method for determining soil nitrogen availability (both the total and easily hydrolyzed nitrogen method were used), but also a reliable method for determining the coefficient of nitrogen utilization from soil as well as data on the coefficient of nitrogen utilization from fertilizer (Nani) for the added quantities of nitrogen fertilizer.
The selenium content of SEPP1 versus selenium requirements in vertebrates  [PDF]
Sam Penglase,Kristin Hamre,Stle Ellingsen
PeerJ , 2015, DOI: 10.7287/peerj.preprints.784v1
Abstract: Selenoprotein P (SEPP1) distributes selenium (Se) throughout the body via the circulatory system. The Se content of SEPP1 varies from 7 to 18 Se atoms depending on the species, but the reason for this variation remains unclear. Herein we provide evidence that vertebrate SEPP1 Sec content correlates positively with Se requirements (R2=0.88). As the Se content of full length SEPP1 is genetically determined, this presents a unique case where a nutrient requirement can be predicted based on genomic sequence information.
Undesirable metals content in wheat of different wheat varieties
Stefanovi? Violeta ?.,Filipovi? Nada K.,Jovanovi? Bogdan M.
Acta Periodica Technologica , 2008, DOI: 10.2298/apt0839069s
Abstract: Selected samples of the different wheat varieties grown in the local region were tested for the content of undesirable metals in wheat grains, bran and flourdetermined by atomic absorption spectrophotometry. The results obtained show significant variations in undesirable metals content in different wheat grains varieties. These results were compared to the maximum values allowed by the pertinent regulations.
On determining the kinetic content of ellipsoidal configurations  [PDF]
Hilario Rodrigues
Physics , 2014, DOI: 10.1093/mnras/stu353
Abstract: Determining the velocity field of structures such as galaxies, stars, and fluid planets is a relevant topic in astrophysics and astronomy. Depending on the shape of the astrophysical object, the internal velocity field may be obtained by means of analytical methods. Specifically, ellipsoidal configurations are the most simple and natural generalization of spherically symmetric mass distributions, when rotation is present. In this work one obtains closed analytical expressions of the velocity field and of the kinetic energy of uniform ellipsoidal configurations composed of compressible fluids. With this aim, the equation of continuity is solved allowing a description of the irrotational velocity field within the system. This permits obtaining analytical expressions of the kinetic energy for each specific mass distribution.
Managing the Selenium Content in Soils in Semiarid Environments through the Recycling of Organic Matter  [PDF]
R. Garcia Moreno,R. Burdock,María Cruz Díaz álvarez,J. W. Crawford
Applied and Environmental Soil Science , 2013, DOI: 10.1155/2013/283468
Abstract: Around 30% of the world’s population suffers from either a lack of one or more essential micronutrients, or the overconsumption of these minerals, which causes toxicity. Selenium (Se) is a particularly important micronutrient component of the diet with a well-documented and wide-ranging role in maintaining health. However, this important micronutrient can be lacking because soil and crop management are focused on high yields to the detriment of the quality of crops required to ensure a healthy human diet. Currently around 15% of the global population has selenium deficiency. This paper focuses on Se availability in semiarid soils and how micronutrients can be effectively managed through the recycling of organic matter. Because many mineral reserves are being exploited unsustainably, we review the advantages of using organic by-products for the management of the biofortification of Se in crops. This type of practice is particularly useful in arid and semiarid environments because organic matter acts as a reservoir for Se, preventing bioaccumulation and leaching. There are also potential local economic benefits from using organic by-products, such as manures and sewage sludge. 1. Introduction At least 60% of the world’s population either lacks one or more essential mineral elements or consumes food containing high amounts of toxic mineral elements [1]. Mineral malnutrition is a widespread problem in both developing and developed countries. This situation is particularly serious for some micronutrients, such as Fe, Zn, I, Se, Ca, Mg, and Cu [2, 3]. In the specific case of Se, 15% of the world’s population is already Se deficient [2]. Gupta et al. [4] stated that, in addition to the lack of studies on the ability of plants to uptake minerals, there are insufficient analyses of soil that determine the total nutrient contents. Similarly, there are no studies of the impact of different soil management practices on the concentration and distribution of micronutrient concentrations in the different edible parts of crop plants. The micronutrient status of a plant can be measured from the leaves because leaves contain the highest amounts of micronutrients. Micronutrient deficiency is easily detected in younger leaves, whereas toxicity can be detected in later stages of development in older leaves [5]. Several factors control the lack of Se content in plants including the genetic variety, soil management, soil type, and climate. The lack of micronutrient content in plants is common in humid temperate and tropical regions due to intense soil leaching caused by the
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