一氧化氮缓解盐胁迫对玉米生长的抑制作用

Nitric Oxide Alleviates Growth Inhibition of Maize Seedlings Under NaCl Stress

研究了一氧化氮(nitri coxide，NO)对NaCl 100mmol／L胁迫下玉米幼苗生长的影响。结果表明：0.1～200μmol／L的NO供体硝普钠(sodium nitroprusside．SNP)，特别是100μmol／LSNP处理可以显着提高盐胁迫下玉米幼苗的干物质积累速率。100μmol／L的SNP处理还显着提高了叶绿素含量、植株体内K^+／Na^+比和(Spd+Spm)／Put的比值，降低膜透性。推测NO对盐胁迫下玉米生长抑制的缓解作用是由于NO促进根系对K^+的选择性吸收及其向地上部的运输，而降低对Na^+的吸收及其向地上部的运输，并促进Put向Spd和Spm的转化。

The effect of nitric oxide (NO) on growth of maize seedlings under 100 mmol/L NaCl stress was studied. The results showed that 0.1-200 μmol/L sodium nitroprusside (SNP), especially 100 μmol/L SNP, increased dry accu- mulation in maize seedlings significantly (Fig. 1B), the chlorophyll content (Fig.2A), K+/Na+ ratio and (Spd+Spm)/Put ratio (Tables 1, 2), and decreased electrolyte leakage (Fig.2B). These results suggest that NO may alleviate the dam- age caused by NaCl stress through increasing K+ uptake and transport to shoots and decreasing Na+ uptake and transport, and also through en- hancing the conversing of Put to Spd and Spm.