Seed cobalt in Lupinus angustifolius

Abstract

The concentration of cobalt in seeds of Lupinus angustifolius varied widely from 6 ng/g to 730 ng/g. High concentrations of cobalt were associated with high concentrations in cotyledons and embryo with much lower concentrations in the seed coat. The effect of the cobalt content of seeds on the response of two cultivars of L. angustifolius to cobalt application was examined in a glasshouse trial. Plants of the Unicrop cultivar grown from seed with a cobalt concentration of 730 ng/g did not respond to cobalt application. By contrast plants grown from seed with a much lower cobalt concentration (10 ng/g) responded markedly. In the Uniharvest cultivar increasing the seed cobalt concentration from 6 to 27 ng/g by cobalt application to the seed crop as a soil dressing did not reduce the extent of a very marked response to cobalt application.