Selenomethionine and Total Methionine Ratio is Conserved in Seed Proteins of Selenium-Treated and Nontreated Soybean, Flax, and Potato (original) (raw)
Related papers
Plant and Soil, 2005
Critical levels of selenium in raya (Brassica juncea Czern L.), maize (Zea mays L.), wheat (Triticum aestivum L.) and rice (Oryza sativa L.) were worked out by growing these crops in an alkaline silty loam soil treated with different levels of selenite-Se ranging from 1 to 25 lg g )1 soil. Significant decrease in dry matter yield was observed above a level of 5 lg Se g )1 soil in raya and maize; 4 lg Se g )1 soil in wheat and 10 lg Se g )1 soil in rice shoots. The critical level of Se in plants above which significant decrease in yield would occur was found to be 104.8 lg g )1 in raya, 76.9 lg g )1 in maize, 41.5 lg g )1 in rice and 18.9 lg g )1 in wheat shoots. Significant coefficients of correlation were observed between Se content above the critical level and dry matter yield of raya as well as rice (r = )0.99, P £ 0.01), wheat (r = )0.97, P £ 0.01) and maize ((r = )0.96, P £ 0.01). A synergistic relationship was observed between S and Se content of raya (r = 0.96, P £ 0.01), wheat (r = 0.89, P £ 0.01), rice (r = 0.85, P £ 0.01) and maize (r = 0.84, P £ 0.01). Raya, maize and rice absorbed Se in levels toxic for animal consumption (i.e. >5 mg Se kg )1 ) when the soil was treated with more than 1.5 lg Se g )1 . In case of wheat, application of Se more than 3 lg g )1 soil resulted in production of toxic plants.
Selenium and agricultural crops
African Journal of Agricultural Research, 2017
Higher plants have different capacities to accumulate and tolerate selenium, referred to as accumulative and non-accumulative plants. Selenium-accumulators plants may contain hundreds of times more selenium than non-accumulators even when grown in the same soil, or can also grow in soils with low and medium selenium reserves; while selenium non-accumulator plants present low accumulation and tolerance to high selenium levels in the culture medium. Several studies have demonstrated the protective role of selenium in relation to oxidative stress in plants. Depending on the dose used, Se can activate certain enzymes such as superoxide dismutase, glutathione reductase and glutathione peroxidase. These enzymes are activated in the presence of Se, reducing the rate of lipid peroxidation and formation of hydrogen peroxide in plant tissue cells, which results in reduced senescence. Symptoms of selenium toxicity include reduced growth, chlorosis of leaves and pink coloration of the roots, yellowing of leaves and black spots. Studies provide evidence on a beneficial role of Se in plants and for environmental phytoremediation. However more research is needed to consolidate the beneficial effects of Se in plants.
Selenium in the Soil-Plant Environment: A Review
International Journal of Applied Agricultural Sciences
Selenium (Se) exhibits a "double-edged" behavior in animal and human nutrition. It is a micronutrient required in low concentrations by animals and humans, but toxic at high concentrations. Selenium deficiency has been associated with cancer and other health problems. Selenium requirements are commonly met through soils and plants such as wheat, rice, vegetables and maize in many countries. Selenium concentration in the soil generally ranges from 0.01-2.0 mg kg-1 but seleniferous soils usually contain more than 5 mg kg-1. Seleniferous soils have been reported in Ireland, China, India and USA. Weathering of parent rocks and atmospheric deposition of volcanic plumes are natural processes increasing Se levels in the environment. Anthropogenic sources of Se include irrigation, fertilizer use, sewage sludge and farmyard manure applications, coal combustion and crude oil processing, mining, smelting and waste incineration. Mobility of Se in the soil-plant system largely depends on its speciation and bioavailability in soil which is controlled by pH and redox potential. Plant uptake of Se varies with plant species and Se bioavailability in the soil. The uptake, translocation, transformation, metabolism, and functions of Se within the plant are further discussed in the paper. The release of Se in soils and subsequent uptake by plants has implications for meeting Se requirements in animals and humans.
Rates of Selenium Volatilization among Crop Species
Journal of Environment Quality, 1992
The rate of Se volatilization per plant was measured for 15 crop species grown hydroponically (for 18-48 d depending on the species) in growth chambers. Selenium was supplied as 20 micromolar sodium selenate in 0.25 strength Hoagland's solution. Selenium volatilization was determined by enclosing plants in a Plexiglas plant chamber and trapping the volatile Se emissions in alkaline peroxide traps. The results show that rice (Oryza sativa L. ), broccoli (Brassica oleracea botrytis L.), and cabbage (Brassica oleracea capitata L.) volatilized Se at the fastest rates, i.e., 200 to 350 Ixg Se per m 2 leaf area per day (1500-2500 l~g Se kg -i plant dry wt. d-~). Carrot (Daucus carota L.), barley (Hordeum vulgare L.), alfalfa (Medicago sativa L.), tomato (Lycopersicon esculentum Mill.), cucumber (Cucumis sativus L.), cotton (Gossypium hirsutum L.), eggplant (Solanum melongena L.), and maize (Zea mays L.) had intermediate rates of 30 to I00 p~g Se m -z d -~ (300-750 ~g Se kg -I d-l). Sugarbeet (Beta vulgaris L.), bean (Phaseolus vulgaris spp.), lettuce (Lactuca sativa L.), and onion (Allium ¢epa L.) had the lowest rates, i.e., less than 15 p~g Se m -~ d -~ (<250 ~g Se kg -~ d-~)
Improving selenium status in plant nutrition and quality
Journal of soil science and plant nutrition, 2015
Selenium (Se) is an essential micronutrient for human health due to its antioxidant capabilities. The Se content around the world is highly variable from 0.005 mg kg-1 in areas from China and Finland to 8,000 mg kg-1 in seleniferous soils from Tuva-Russia. However, about one billion of people in the world wide are Se deficient. During the last decade, studies related with strategies for Se biofortification in food plants for human nutrition have significantly increased because this metalloid is incorporated into human metabolism mainly as a constituent of food plants. Similarly, Se biofortification is important in pastures for increasing the Se content in cattle to enrich meat and to prevent disease associated to Se deficiency as white muscle disease. In China, two endemic diseases have been related to Se deficiency: Keshan and Keshin-Beck diseases. Agronomic biofortification by using inorganic Se sources is a current practice in countries as China, Finland, and USA. In Chile, fertilization by using chemical compounds with Se is an uncommon practice due the edaphoclimatic characteristics of Andisols, which represent around 60% of agricultural soils of southern Chile. Recent studies showed that microorganisms as bacteria and arbuscular mycorrhizal fungi play an important role in the transformations and Se availability, representing an interesting biotechnological alternative to Se biofortification. This review is focalized to describing Se behavior in soil-plant system and the possible strategies to improving Se content, including the use of microorganisms as biotechnological tools for increasing plant nutrition and quality. Specific attention will be devoted to volcanic soils of Southern Chile, where different factors concur to enhance the Se-deficiency problem.
Chemosphere, 2007
Greenhouse experiments were conducted to study the bioavailability of selenium (Se) to sorghum (Sorghum bicolor L.), maize (Zea mays L.) and berseem (Trifolium alexandrinum L.) fodders in a sandy loam soil amended with different levels of Se-rich wheat (Triticum aestivum L.) and raya (Brassica juncea L. Czern) straw containing 53.3 and 136.7 lg Se g À1 , respectively. Each of the fodder crops was grown after incorporation of Se-rich materials either individually or in a sequence -sorghum-maize-berseem by incorporating Se-rich straws only to the first crop. Application of Se-rich straws to each crop, even at the greatest rate of 1%, did not have any detrimental effect on dry matter yield of different crops. With increase in the level of wheat straw from 0% to 1%, Se content in sorghum and maize plants increased to greatest level of 1.3 and 1.5 lg g À1 , respectively, at 0.3% of applied straw and thereafter it decreased consistently. In case of raya straw, the greatest Se content in sorghum (2.3 lg g À1 ) and maize (3.0 lg g À1 ) was recorded at 0.3% and 0.4% of the applied straw, respectively. Unlike sorghum and maize fodders, Se content in all the four cuts of berseem continued to increase with increase in the level of applied straws and for different cuts of berseem it varied from 1.6 to 2.3 and 3.4 to 4.3 lg g À1 in case of wheat and raya straw, respectively. Similar variations in Se content of different fodder crops were recorded when these were grown in the sequence -sorghummaize-berseem; but Se content was 2-4 times lower than when each crop was grown with fresh application of Se-rich straw. None of the fodders absorbed Se in levels toxic for animal consumption (>5 lg g À1 ) even at the greatest level of applied straw. Of the total Se added through Se-rich straws, utilization of Se was not more than 2% in case of sorghum and maize crops and up to 5% in case of berseem.
Plant and Soil, 2013
Aims A comparison was performed between plant species to determine if extractable, rather than total soil Se, is more effective at predicting plant Se accumulation over a full growing season. Methods Durum wheat (Triticum turgidum L.) and spring canola (Brassica napus L.) were sown in potted soil amended with 0, 0.1, 1.0, or 5.0 mg kg −1 Se as SeO 4 2− or SeO 3 2−. In addition, SeO 4 2−-amended soils were amended with 0 or 50 mg kg −1 S as SO 4 2−. Soils were analyzed for extractable and total concentration of Se ([Se]). Twice during the growing season plants were harvested and tissue [Se] was determined. Results Plants exposed to SeO 3 2− accumulated the least Se. Fitted predictive models for whole plant accumulation based on extractable soil [Se] were similar to models based on total [Se] in soil (R 2 =0.73 or 0.74, respectively) and selenium speciation and soil [S] were important soil parameters to consider. As well, soil S amendments limited Se toxicity. Conclusions Soil quality guidelines (SQGs) based on extractable Se should be considered for risk assessment, particularly when Se speciation is unknown. Predictive models to estimate plant Se uptake should include soil S, a modifier of Se accumulation.
Annual Review of Plant Physiology and Plant Molecular Biology, 2000
Plants vary considerably in their physiological response to selenium (Se). Some plant species growing on seleniferous soils are Se tolerant and accumulate very high concentrations of Se (Se accumulators), but most plants are Se nonaccumulators and are Se-sensitive. This review summarizes knowledge of the physiology and biochemistry of both types of plants, particularly with regard to Se uptake and transport, biochemical pathways of assimilation, volatilization and incorporation into proteins, and mechanisms of toxicity and tolerance. Molecular approaches are providing new insights into the role of sulfate transporters and sulfur assimilation enzymes in selenate uptake and metabolism, as well as the question of Se essentiality in plants. Recent advances in our understanding of the plant's ability to metabolize Se into volatile Se forms (phytovolatilization) are discussed, along with the application of phytoremediation for the cleanup of Se contaminated environments.
Plant species and growing season weather influence the efficiency of selenium biofortification
Nutrient Cycling in Agroecosystems, 2019
Se deficiency is widespread in agricultural soils; hence, agronomic Se biofortification is an important strategy to overcome its deficiency in humans and animals. In Finland, fertilizers have been amended with inorganic Se for over 20 years to reverse the negative effects of low Se content in feed and food. Plant species, climatic conditions, other nutrients and soil properties affect the efficiency of Se biofortification. The present two years' study compared the ability of oilseed rape, wheat and forage grasses to uptake fertilizer Se applied as sodium selenate in a sub-boreal environment. The effect of foliar N application on Se uptake was tested in the second year. Se concentration was determined in plant parts and in soil samples taken at the end of growth season in both years as well as from another plot where Se fertilizer had been used for 20 years. Se fertilizer recovery in harvested wheat and oilseed rape was 1-16%, and in forage grasses was 52-64% in the first harvest and 15-19% in the second harvest. Foliar N application improved Se uptake only at the higher Se fertilizer level. The efficiency of biofortification depended on weather conditions, with forage grasses being the most reliable crop. Oilseed rape as a Se semi-accumulator had no advantage in Se biofortification in field conditions due to low translocation to seeds.