裙带菜(Undaria pinnatifida)配子体对氨态氮和硝态氮的吸收利用比较

COMPARISON IN ASSIMILATION OF AMMONIA NITROGEN AND NITRATE NITROGEN BY UNDARIA PINNATIFIDA GAMETOPHYTES

本文对裙带菜(Undaria pinnatifida)配子体丰富培养的氮源进行了研究,结果发现裙带菜配子体能够有效利用氨态氮和硝态氮进行扩增,在30μmol/L氮离子浓度条件下,裙带菜配子体的日生长率能达到25%,可以满足配子体快速扩增的需要。裙带菜配子体在同时含有硝态氮和氨态氮的培养液中培养时,同时吸收两种氮源,并没有出现相互抑制的现象;配子体对氨态氮的吸收速率略大于硝态氮的吸收;对裙带菜配子体的氮吸收速率进行了测定,吸收速率最高分别可达24.3μmol/(g·h)和20.73μmol/(g·h),吸收速率随着氮浓度的增加而升高。

We studied nitrogen uptake by mass-cultured Undaria pinnatifida gametophytes from different nitrogen sources（in ammonium and nitrate） in different concentration and combination in experiment. The result shows that U. pinnatifida gametophytes can take nitrogen effectively for growth from both sources. In nitrogen ion concentration of 30μmol/L, the daily growth rate could reach 25%, which is able to meet the needs of rapid growth of the gametophytes. In the medium containing both ammonium and nitrate nitrogen sources the gametophytes could use the both with no reciprocal inhibition effect. The absorption rate of ammonium nitrogen by gametophytes was slightly greater than that of nitrate nitrogen. The maximum nitrogen absorption rate reached 24.3 and 20.73μmol/（g·h） for ammonium and nitrate, respectively, and the absorption rose with the increase of nitrogen concentration.