盐碱胁迫对向日葵子叶渗透调节及离子平衡的影响

研究了盐碱胁迫对向日葵子叶渗透调节及离子平衡的影响.以向日葵品种白葵杂6号为试验材料,中性盐NaC1、Na2SO4及碱性盐NaHCO3、Na2CO3分别按摩尔比9∶1混合模拟盐胁迫、碱胁迫,各设计2种处理.结果表明,盐碱胁迫下,向日葵子叶中起渗调作用的主要无机离子和有机离子分别为K+、有机酸.通过试验结果推测,为了适应盐、碱胁迫,向日葵可能在体内启动了特殊的钠钾吸收转运通道,并且通过大量合成有机酸来维持细胞内离子平衡及pH稳定.

Effects of salt and alkali stresses on osmotic adjustment and ionic balance in sunflower cotyledon

Using a sunflower variety (Helianthusannuus L. cv. Baikuiza 6) as the test material, the effects of salt and alkali stresses on osmotic adjustment and ionic balance in sunflower ctyledons were compared. The stress conditions of two salinities and two alkalinities were simulated by mixing two neutral salts (NaCl and Na₂SO₄) and two alkaline salts (NaHCO₃ and Na₂CO₃) in the molar ratio of 9:1. The results showed that the main inorganic and organic osmolytes were K⁺ and organic acid, respectively in the cotyledon under salt and alkali stresses. Therefore, we speculated that there would be a special mechanism for controlling transport of Na⁺ and K⁺ in sunflower. Synthesized organic acids in sunflowers might be used to keep ion balance and adjust pH.