Uptake of native and applied selenium by pasture species

Abstract

Uptake by white clover (Trifolium repens) and by browntop (Agrostis termis) of selenium applied at 1 oz per acre as sodium selenite to Atiamuri sand was studied in 2 pot experiments. In the experiment with white clover sodium selenite was applied (1) over the foliage mixed with superphosphate, (2) over the foliage in solution, (3) to the soil in solution without touching the herbage. Selenium was taken in readily through the leaves, particularly from the solution, and distributed to stolons and roots. Uptake through the roots was much slower. In (3) the concentration of selenium was in the order: roots > stolons > nodules > leaves and petioles. Browntop was treated with sodium selenite in solution as in (2) and (3) for white clover, together with a control treatment. It showed little evidence of ability to absorb selenium through the leaves, but a very much greater ability than white clover to absorb it through the roots.