Phytoavailability and toxicity of beryllium and vanadium

Abstract

Greenhouse and laboratory studies were conducted to evaluate the toxic effects of Be and V on collards (Brassica oleracea, var. acephala L.). In the laboratory germination study, incremental increases in the Be concentrations of the growing medium induced a steady decline in the radicle length of seven-day-old collard seedling. Beryllium concentrations greater than or equal to 8 mg Be L⁻¹ totally inhibited seed germination. The presence of V in the growing medium had no effect on collard germination; however, it had a profound effect on subsequent radicle elongation. Concentrations of V less than 1 mg V L⁻¹ stimulated radicle elongation, while concentrations greater than or equal to 3 mg V L⁻¹ caused severe toxicity. In the greenhouse study, Be toxicity was observed in collards grown in a Blanton sand (Grossarenic Paleudult) received treatments greater than or equal to 150 mg Be kg ⁻¹ (as BeSO₄). Irrespective of treatment level, 97% of the Be taken up by the plants remained in the roots while only 3% was translocated to aboveground plant parts. Vanadium tissue concentrations and toxicity to collards varied with soil type. Additions as low as 80 mg V kg⁻¹ to the Blanton sand significantly reduced collard biomass while additions as high as 100 mg V kg⁻¹ to an Orangebury loamy sand (Typic Paleudult) had no effect on plant biomass. The differential response was attributed to greater accumulation of V by plants grown in the Blanton soil.