渗透胁迫与植物细胞的氮代谢

比较了在渗透胁迫下苜蓿耐旱（ＭＥＳ—３）和非耐旱（ＭＥＳ—０）两个悬浮细胞系，它们的生长速率，细胞内ＮＨ３－ＮＨ４＋浓度的变化以及与精氨酸生物合成的关系。用１６％ＰＥＧ（聚乙二醇）处理作为渗透胁迫。在胁迫下培养１４天，ＭＥＳ—０的细胞生长速度明显下降，比对照降低８５．９７％；ＭＥＳ—３比对照下降３３．３６％；ＮＨ３—ＮＨ４＋含量ＭＥＳ—０高于对照１．９倍；ＭＥＳ—３则低于对照３４．８３％。精氨酸生物合成量ＭＥＳ—０低于对照５３．０１％，ＭＥＳ—３则相反，高于对照５４．２３％。

OSMOTIC STRESS AND NITROGEN METABOLISM IN PLANT CELL

The effect of 14d of osmotic stress on suspension culture cells of alfalfa (Medicago sativa L. )was investigated. Cells growth rate, NH3 - NH4 content and arginine biosynthesis were compared in drought-tolerant (MES- 3) and drought-sensitive (MES-0) alfalfa cells. Alfalfa cultures were treated by 16% PEG (Polyethyeneglycol). After 14d, cells growth rate of the MES- 0 and MES- 3 were inhibited 85. 97 % and 33.36% respectively: MES- 0 accumulated higher levels of NH3 - NH4 by 1. 9 - fold,MES- 3 was decreased by 34. 83%. The activity of the de novo arginine biosynthtic pathway was decreased by 53. 01 % in MES-0 and increased by 54. 23% in MES-3.