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作 者 ：王学奎;李合生;刘武定;伍素辉;孙晶晶

期 刊 ：植物营养与肥料学报 2000年 6卷 1期 页码：42-47

关键词：钙螯合剂；小麦；氮代谢；硝酸还原酶；谷氨酰胺合成酶；

Keywords:calcium chelator, wheat, nitrogen metabolism, nitrate reductase, glutamine synthetase,

摘 要 ：营养液中添加钙螯合剂EGTA[Glycol bis (α aminoethyl)etherN ,N ,N′ ,N′ tetraaceticacid ,乙二醇双 (α-氨基乙基 )醚四乙酸 ]导致小麦幼苗干物质累积下降 ,降低地上部和地下部全钙含量 ,抑制小麦幼苗对外源硝态氮的吸收及其向地上部的运输 ,改变其在不同器官中的分配比例和影响其向氨基氮或可溶性蛋白质的转化。叶片和根中硝酸还原酶活性与相应器官中的NO₃^--N含量相关 ,叶片中谷氨酰胺合成酶 (GS)活性在EGTA处理后明显下降 ,根中GS活性变化不显著。

Abstract:Calcium chelator EGTA (Glycol-bis-(α-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.

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