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Garden rocket (Eruca sativa L.) plants grown in sand culture were irrigated with normal 1/10 Hoagland's medium [low sulfate (SO42−)] or with double SO42− concentration (high SO42−), each supplemented with 0, 2, 10 ppm SeO42− as sodium selenate for 30 days. Increasing SO42− concentration in the nutrient medium diminished SeO42− uptake, foliar hydrogen peroxide (H2O2), and MDA via enhancing the glutathione pool and their enzyme activities. These results showed that increasing SO42−/SeO42− ratio in nutrient medium of rocket plants played an important role in selenate detoxification.

Since studies on the effects of selenium (Se) supplementation in water-stressed plants have mainly focused on cereal crops, the specific reports regarding Se-mediated adaptation to drought stress in medicinal vegetables are scant. Thus, we investigated the responses of Melissa officinalis to Se supplementation. Selenium contents were increased in leaves and grains by supplemental Se. Selenium foliar application at 1 mg l−1 could be useful to increase the vegetative and reproductive growth of Se-enriched plants under well-watered conditions but at 20 mg l−1 led to toxicity and caused damage to shoots. Drought stress significantly inhibited plant growth by chlorophyll degradation and reduced net carbon dioxide (CO2) assimilation rate. Although Se at 1 mg l−1 could increase biomass production under well-watered conditions in addition to the stimulation of antioxidant system under water stress, it could not ameliorate the negative effect of drought on productivity.

Watercress (Nasturtium officinale R. Br.) produces carotenoids and sulfur-containing glucosinolates (GSs) beneficial to human health. Selenium (Se) imparts dietary health properties and substitutes for S in plant biochemical pathways. Experimental objectives were to determine the influence of Se fertilization on 1) biomass, 2) elemental accumulations, 3) carotenoids, and 4) glucosinolates in watercress leaf and shoot tissues. Watercress was greenhouse grown in solution culture with Se treatments of 0, 0.125, 0.25, 0.50, 1.0, 2.0, and 4.0 mg Se L−1, delivered as sodium selenate (Na2SeO4). Fresh and dry biomass were unaffected while shoot tissue Se (P = 0.057) and S (P = 0.003) increased linearly in response to increasing Se treatments. Linear decreases were measured for β-carotene (P = 0.017) and lutein (P = 0.018) in response to increasing Se. Total levels of GS increased, then decreased quadratically (P = 0.003). Results indicate that Se supplementation can increase Se tissue concentrations and GS in wat...

The mineral composition and maintenance of mineral balance are important to growth and development of plants. The selenium (Se) has not been described as an essential element for plants, although there are studies that have demonstrated to interaction between Se with other mineral nutrients. The aim was to evaluate the influence that Se application at different rates and forms exerts on the nutritional state in lettuce plants. The plants were grown under different treatments: 5, 10, 20, 40, 60, 80, 120 μmol L−1 as sodium selenate [Na2SeO4 or Na2SeO3]. All the plants growth under controlled conditions. The results showed changes in some of the essential nutrients inside of plants such as nitrogen (N), phosphorous (P), iron (Fe), copper (Cu), calcium (Ca). The effect of Se depended largely on the Se from was applied to the culture medium. Thus, the selenite application had a stronger effect on the nutritional state of the plant.

Selenium (Se) deficiency in Scandinavian soils is a common problem, and crops generally contain inadequate amounts to meet human need. This study shows a relationship of the Se concentration in spring wheat (Triticum aestivum L., c.v. ‘Helena’) and leaching water with timing of nitrogen (N) [as ammonium nitrate (NH4NO3)] and Se [as sodium selenate (Na2SeO4)] application. Ammonium-nitrate was applied by two methods (i) whole amount at sowing and (ii) in split application as 75% at sowing and 25% at stem elongation. Selenate was applied at cereal growth stages after sowing, e.g., tillering, stem elongation, head emergence, and milking. Split N application in comparison to one N application increased the grain protein content from 12.1 to 13.7 mg g− 1, and grain Se was increased from 0.8 to 1.1 mg kg− 1 when Se was applied at stem elongation and from 0.6 to 0.9 mg kg− 1 when applied at heading. The highest Se concentration in plant was achieved with the split N application and Se application at stem...

Breeding plants to be more efficient at micronutrient accumulation is a proposed strategy for fighting worldwide malnutrition of humans. Selection for increased selenium (Se) in Brassica oleracea L. is possible. However, when present at high levels, micronutrients such as Se can affect seed germination and subsequently hamper breeding efforts. The objectives of this study were: (1) to evaluate the accumulation of Se in seeds of B. oleracea; and (2) to determine effects that Se accumulation may have on seed germination. Plants of a rapid‐cycling B. oleracea population were grown in nutrient solutions with sodium selenate (Na2SeO4) concentrations up to 7 mg L−1 (2.93 mg Se L−1). Seeds and leaves were harvested from the selenized plants and analyzed for Se content using atomic absorption spectrophotometry. Germination percentage and rate were determined by sowing seeds in moistened towels, placing them in an incubator at 21°C, and observing radicle emergence. Selenium accumulated in the seeds, but a...

Brassica oleracea L. are important economic vegetables, and are capable of selenium (Se) enrichment to enhance human nutrition and health. Because Se enrichment may influence the nutrient balance of this crop, a study was done to test the effects of selenate‐Se on plant nutrients. Plants of a rapid‐cycling B. oleracea population were grown in nutrient solutions amended with Na2SeO4at 0.0, 3.0, 6.0, and 9.0 mg L‐1. Leaf tissue was then analyzed for nutrient content. Boron (B) (P=0.01), iron (Fe) (P=0.01), and phosphorus (P) (P=0.01) content decreased, while Se (P=0.01), sulfur (S) (P=0.01), and potassium (K) content (P=0.01) increased with increasing selenate‐Se treatments. Significant quadratic responses were found for magnesium (P=0.01) and molybdenum (P=0.01). No significant differences in leaf fresh or dry weight were detected. Changes in plant nutrient content can be expected when Brassicas are enhanced for delivery of beneficial organic Se.

Field studies were conducted at two locations in P.E.I., Canada on cereals and forages on the effect of soil applications of Selcote® Ultra and on a comparison of sodium selenate (laboratory versus commercial grade) on selenium (Se) concentration in plant tissue. Soil at both locations was sandy loam in texture and the soil pH ranged from 5.8 to 6.0. The data showed that 5 g Se ha‐1 added as Selcote® Ultra was adequate to raise the Se level in the first two cuts of forage tissue above the minimum required level of 100 ug kg‐1. For cereals, 10 g Se was necessary to achieve the same level. The residual effect of 10 g Se ha‐1 from Selcote® Ultra added in the first year maintained plant Se at >100 μg kg‐1 in the second year in the first cut of alfalfa at one location and ryegrass at both locations. A comparison of selenate‐Se (laboratory vs commercial grade) showed that both sources at similar levels of Se fertilization were equally effective in enriching barley grain with Se with no significant diff...