水杨酸浸种对NaCl胁迫下棉花种子萌发和幼苗根系生长的影响
Effects of salicylic acid soaking on seed germination and root growth of cotton under salt stress

为探讨水杨酸(SA)浸种对NaCl胁迫下棉花生长的影响,以中棉所41号、中棉所49号、新陆中36号和新陆中21号为材料,通过沙床萌发试验,研究了SA对NaCl胁迫下棉花种子萌发和幼苗根系生长的影响。结果表明:1)2.3 mg/mL NaCl使棉花种子的相对盐害率达50.54%~83.02%,4个品种因耐盐性的不同其相对发芽势、相对发芽率和相对发芽指数下降的幅度也不相同;2)0.2 mmol/L SA对棉花种子的盐害缓解效应达到显著水平;3)通过对各指标灰色关联度分析,发现发芽势、发芽率和发芽指数能作为评价SA对NaCl缓解作用的萌发指标,植株干重和根系活力能作为幼苗阶段评价SA对NaCl缓解作用的指标。总之,适宜浓度的SA可以显著提高棉花种子萌发,缓解NaCl胁迫对植株的伤害,同时可提高棉花幼苗的根系活力。
To explore the effect of Salicylic acid (SA) on the cotton germination under NaCl stress, Zhongmiansuo 41, Zhongmiansuo 49, Xinluzhong 36 and Xinluzhong 21 were used as experimental materials.The results showed that:1) The relative salt damage rate of 2.3 mg/mL NaCl to cotton seed is 50.54%-83.02% and the four materials reacted differently due to their difference in salt tolerance;2) Mitigation effect of salt stress on cotton seeds soaked in 0.2 mmol/L SA reached significant level;3) Gray correlation degree analysis discovered that the germination potential, germination rate, germination index could be adapted as index of SA alleviate effect to NaCl at cotton seed germination stage.And plant dry weight, root vigor can be used to evaluate SA alleviate effect at seedling growth stage.In summary, suitable concentration of SA can significantly improve cotton seed germination, mitigate salt stress on plants, and enhance root activity of cotton seedlings.