氮素形态对兴安落叶松幼苗的营养效应

Nitrogen Forms on the Growth of Larix gmelinii Seedings

采用水培试验方法,以兴安落叶松(Larix gmelinii)幼苗为供试材料,研究兴安落叶松幼苗对氨基酸态氮(甘氨酸、谷氨酸、赖氨酸)、铵态氮(硫酸铵)、硝态氮(硝酸钙)的吸收与响应特性。结果表明:氨基酸态氮和铵态氮对兴安落叶松幼苗的生长及干物质积累的促进作用明显好于硝态氮。氨基酸态氮比无机态氮更能有效提高幼苗体内N、P、K养分质量分数,甘氨酸、谷氨酸对兴安落叶松幼苗铵态氮的供应能力与硫酸铵等效,赖氨酸态氮次之。氨基酸态氮和铵态氮对兴安落叶松幼苗硝态氮的供应无明显效果。供应氨基酸态氮和硝态氮后,营养液pH值显著升高;供应铵态氮,营养液pH值显著下降。

We studied the effect of nitrogen forms of amino acids （ glycine, glutamate or lysine） , Ammonium-N （ ammonium sul- fate） or Nitrate-N （ calcium nitrate） on the growth of Larix gmelinii seedlings with water culture system in greenhouse. The effects of amino acid and ammonium nitrogen on the growth and dry matter accumulation of Larix gmelinii seedlings were better than that of nitrate. Amino acid nitrogen was more effective than inorganic nitrogen to enhance nutrient concentration of N, P and K in seedlings. The capability of supply NH4^＋N with glycine or glutamate were similar with ammonium sulfate. There are no significant effects in the capability of supply NO3-N with amino acids （glycine, glutamate or lysine） or ammonium sulfate. The pH of cultural medium was affected markedly by the nitrogen forms, which was increased with increasing amino acid or NO3-N and decreased with increasing NH4^＋-N.