Abstract: Proline(Pro),Pyrroline-5-carboxylate synthetase(P5CS),Ornithine-oxo-acid transaminase(δ-OAT),and Proline dehydragenase(ProDH) of leaves and roots from Saussurea runcinata were analyzed to assess the proline metabolism and salinity tolerance of Saussurea runcinata seedlings.The study design includes six treatments and one control with varying levels of either NaCl or Na₂SO₄.Results show that the proline content increased with increasing the concentration of either NaCl or Na₂SO₄.The pathway of Ornithine is a main synthesis pathway for proline metabolism in Saussurea runcinata seedling under salt stress.Proline metabolism of Saussurea runcinata seeding is most vigorous under 300 mmol/L salt stress(either NaCl or Na₂SO₄),while Saussurea runcinata seedings have more tolerant to NaCl stress than to Na₂SO₄ stress.These results also provide a database for restoration and improvement of Saline-alkali soil.

Key words: Salt stress, Saussurea runcinata, Proline metabolism, δ-OAT, P5CS, ProDH

摘要： 通过对碱地风毛菊(Saussurea runcinata)苗期分别以NaCl和Na₂SO₄进行胁迫,设6个浓度和1个对照,测定其脯氨酸含量及δ-氨基转移酶、吡咯啉-5-羧酸合成酶和脯氨酸脱氢酶活性,以探讨其苗期耐盐性及脯氨酸代谢途径,并为盐碱地植被恢复与改良提供依据。结果表明:NaCl和Na₂SO₄胁迫下,碱地风毛菊的脯氨酸含量随NaCl和Na₂SO₄胁迫浓度增加而增高,在盐胁迫下,碱地风毛菊的脯氨酸合成途径以鸟氨酸途径为主;且在300mmol·L^-1的盐浓度胁迫下碱地风毛菊苗期的脯氨酸代谢最为旺盛,其对NaCl胁迫的耐性较高。

关键词: 盐胁迫, 碱地风毛菊, 脯氨酸代谢, δ-氨基转移酶, 吡咯啉-5-羧酸合成酶, 脯氨酸脱氢酶