Abstract
Keywords: Eucalyptus / nitrogen / uptake / amino acid / competition Abstract • Nitrogen (N) exists in the soil in a variety of different forms and thus plants may avoid competition by taking up N as different chemical forms. • This study examined the uptake of nitrate, ammonium and glycine by three co-occurring species of Eucalyptus (E. obliqua, E. radiata and E. rubida) from dry sclerophyll forest in south-eastern Australia. Species preference for N forms was determined by measuring uptake of glycine, nitrate and ammonium from 15 N-labelled solutions containing equimolar 100 μmol L −1 concentrations of all three N forms. KCl extracts were used to assess the relative abundance of the different forms of N in the soil's exchangeable pool. • KCl extracts of soil indicated that amino acids comprised 30-40% of the soluble non-protein N, while ammonium varied from 10-70% and nitrate from 5-70%. In all species, ammonium was the preferred source of nitrogen and was taken up 2.5-4.5 times faster than glycine, and 30-50 times faster than nitrate. Species did not differ in preference for N-forms (species*N-form interaction, not
Submitted Version (
Free)
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call