EFFECTS OF CALCIUM CHELATOR ON THE NITROGEN METABOLISM AND DRY MATTER ACCUMULATION IN WHEAT SEEDLINGS

Calcium chelator EGTA (Glycol-bis-(-aminoethyl)ether-N, N, N, N-tetraacetic acid) which was supplied to 1/2 Hoagland cultural solution caused the obvious decrease of total calcium content and dry matter accumulation in wheat seedlings, inhibited the absorption of nitrate and its translocation to up ground parts, changed the distribution ratio of 15N nitrate in different organs, and decreased the synthesis of soluble protein from amino nitrogen in leaf and the transformation of nitrate into amino nitrogen in root. The activities of nitrate reductase (NR) in leaf and root were basically related to the content of nitrate in the relevant organs, the glutamine synthetase(GS) activity in leaf was decreased significantly under EGTA treatment, but the GS activity changed weakly in root.