Differences among Plant Species in Selenium Accumulation from Soils Low in Available Selenium1

Abstract

AbstractThe uptake of Se by several plant species was compared with the uptake of Se by alfalfa under field and greenhouse conditions. Differences among plant species in Se accumulation from soils low in Se were small. Field samples of red clover (Trifolium pratense L.), orchardgrass (Dactylis glomerata L.) and bromegrass (Bromus inermis Leyss.) contained about one‐half the Se concentration of alfalfa (Medicago sativa L.). Astragalus bisulcatus (Hook) Gray, a noted Se accumulator in high‐Se soils, accumulated about five times as much Se as did alfalfa when grown in pots of Dalton silt loam (pH 7.0) which had been treated with 0.75 ppm Se labelled with 75Se. Of the other 22 species tested, the species with the highest Se concentration had only about three times that of the one with the lowest Se concentration. The Se concentration in grasses decreased with increases in the rate of dry matter production, whereas the Se concentration in dicotylendon species, except dandelion (Taraxacum officinale Weber), did not decrease with increase in the rate of dry‐matter production.On soils low in Se, stage of growth had little effect on the Se concentration of alfalfa. Drying at 50 C did not cause postharvest losses of Se.