Response of lupin cultivars to concentration of calcium and activity of aluminum in dilute nutrient solutions

Abstract

Abstract Although lupins (Lupinus angustifolius L.) are usually grown in slightly acidic soils covering the pH range 6.0 to 6.5, the response of lupin cultivars to a range of acid soil infertility factors has not been investigated. Effects of external Ca concentrations of 150 or 1000 μM and S activities of monomeric Al species (Al reactive with aluminon in 30 min, without acidification and heating; SaA1 mono) up to 80 μM on early growth and mineral composition in tops of three lupin cultivars (Unicrop, Uniharvest, and Uniwhite) were investigated in continuously flowing nutrient solution at pH 4.3 ± 0.1. The dry weight of tops of the three cultivars was generally similar in Uniwhite and Unicrop, and considerably lover in Uniharvest. The weight of tops increased by 24 to 39% while that of roots increased by 11 to 14% with an increase in Ca concentration from 150 to 1000 μM in Al‐free solutions. At each Ca concentration, an increase in activity of monomeric Al resulted in a linear decrease in dry weight of t...