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作 者 ：杨丽琴;封克;夏小燕;司江英

期 刊 ：植物营养与肥料学报 2007年 13卷 1期 页码：77-80

关键词：氮素形态；pH；小麦；钙分布；根超微结构；

Keywords:nitrogen form, pH, wheat, Ca2+ distribution, root ultrastructure,

摘 要 ：利用电镜技术研究了不同pH(4.0和6.0)和氮形态(NH₄⁺-N和NO₃^---N)对小麦根系超微结构及根中Ca²⁺分布的影响。结果表明,1)pH.4.0处理下细胞结构中Ca²⁺明显少于pH.6.0处理;2)低pH造成质壁分离;3)铵态氮源处理下细胞结构中Ca²⁺明显少于硝态氮源处理,尤其体现在细胞间质、细胞壁、细胞膜上;4)铵态氮源处理也会导致细胞出现质壁分离,细胞结构松散,胞质外流;低pH加重这些现象。

Abstract:Transmission electron microscopy was used to observe effects of two pH levels(4.0 and 6.0)and nitrogen forms(NH₄⁺-N,NO₃^--N) on the root ultrastructure and Ca²⁺ distribution in wheat root.Results obtained were the following: 1) Ca²⁺ content in wheat root cells at the pH 4.0 was lower than that at pH 6.0;2) Low pH could induce plasmolysis of wheat root cells;3) Ca²⁺ in wheat root cells,especially in intercellular substances,cell wall and cell membrane,with NH₄⁺-N as nitrogen source was significant lower than NO₃^--N;and 4)Ammonium nitrogen was also able to induce plasmolysis,structure loss and cytoplasm outflow of wheat root cells.Low pH could exacerbate these symptoms.

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