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We are investigating the biotransfer of accumulated Se by the plant in several phytoremediation systems. In study I, we evaluated the biotransfer of Se from Indian mustard, a Brassica species, to the insect-cabbage looper (Trichoplusia ni); mortality, deterrence, and biomagnification of Se were examined. We determined that feeding behavior of food chain consumers was affected not only by the plant concentration of Se, but also by the mobility of the insects and choice of feed available. In study II, we examined the survival and development of beet armyworm (Spodoptera exigua) fed Se-enriched plant tissues from different lines of saltbush (Atriplex spp.) After feeding on lines of saltbush that produced high biomass and accumulated high concentrations of Se, insect growth and survival was reduced. In studies III, IV, and V, lambs, dairy cows, and rabbits were fed Se-enriched Brassica and Medicago (alfalfa) plants as part of their feed ration. None of the tested animals exhibited any Se toxicity symptoms, but they had increased levels of Se in most tissues sampled (e.g., organs, blood, urine, feces), excluding milk. In study VI, we evaluated biotransfer of Se from broccoli to rats to determine efficacy of Se for reducing colon cancer. We found that Se-enriched plant material was more effective than inorganic sources of Se for preventing precancerous colon lesions. Results from all studies clearly show that Se absorbed by plants can be transferred biologically in an intentional or unintentional manner to insects and animals.

HiMag is an experimental cultivar derived from Missouri 96 (Mo96) and Kentucky 31 (K31) tall fescue (Festuca arundinacea Schreb.) parentage for increased calcium (Ca), magnesium (Mg), and reduced potassium (K)/ (Ca+Mg). Our objective was to determine productivity and mineral characteristics of endophyte-free (E-) HiMag in relation to standard tall fescue cultivars when grown in the Southern Piedmont Land Resource Area. In experiment 1, HiMag (E-) and K31 (E-) were grown at two levels of phosphorus (P), K, and lime additions to both severely eroded, and noneroded Cecil soil (clayey, kaolinitic, thermic family of Typic Hapludults). Herbage Ca and Mg were greater and K/(Ca+ Mg) and yield were less for HiMag than for K31. Phosphorus and K concentrations were not different. Herbage yields, P, Ca, and Mg concentrations were increased by P, K, and lime additions. In experiment 2, HiMag(E-), K31(E-), endophyte-infected K31(E+), Mo I(E+), Mo II (E+), and AU Triumph (E-) were planted either in a prepared seedbed or planted without tillage into the Cecil soil. HiMag yields were not different from Mo-I, Mo-II or K31(E±), but were less than

High soluble‐sulfate (SO4) concentrations affect water quality, soil chemistry, plant sulfur (S) levels, and possibly ruminant‐animal health. The objective of this greenhouse pot study was to determine the potential for accumulating high levels of S by tansy mustard (Descurainia pinnata (Walt.) Britton), kochia (Kochia scoparia L. Schrad.), yellow sweet clover (Melilotus officinalis L.), slender wheatgrass (Elymus trachycaulus (Link) Gould ex Shinners), and sunflower (Helianthus annuus L.). Plants were grown on both a Brinegar (fine‐loamy Ultic Argixeroll) and Portneuf (coarse silty Durixerollic Calciorthid) soil. Each species received five‐SO4 levels. The saturation extract electrical conductivity (EC) of the cropped soils ranged from 6 to 16 dS/m, while the soluble SO4 varied from 16 to 200 mmolc/kg soil. Soil solutions were saturated or very nearly saturated with respect to gypsum at the conclusion of each study. Plant dry matter yield, except of grass growing on the non‐calcareous soil, was n...

The level of soluble tissue phosphorus (PO4‐P) may be correlated with the plant P nutritional status, but the amount extracted depends upon dry matter losses or the amount of enzymatic or heat—induced hydrolysis of organic P compounds during sample drying. Alfalfa (Medieago sativa L) and sugarbeet (Beta vulgaris L) plant parts grown under low and high soil P conditions, were freeze‐dried or oven‐dried at 40, 56, 70, or 100 C. Total K, P, and 0.35 N acetic‐acid‐soluble P (measured as PO ‐P) were determined. Dry matter losses were 0, 6.5, 3.6, 5.5, and 4.9 percent for the respective drying methods. The total‐P values, once corrected for dry matter losses, were not affected by the drying methods. The corrected PO4‐P values were 0.15, 0.17, 0.16, 0.16, and 0.19 percent, while the (PO4‐P)/P values were 0.63, 0.69, 0.67, 0.68, and 0.78 for each of the respective drying methods. The potential utility of extractable PO4‐P in describing the plants’ P nutritional status will depend upon rigorous sampledryi...