盐碱胁迫和NO处理对杂交新美柳根系活力的影响

Effects of alkali-saline stress and NO treatment on root activity of Salix hybrid

以杂交新美柳1年生扦插苗为材料，采用完全随机区组设计，研究NaCl、Na2SO4、NaHCO3、Na2CO3及其混合盐碱胁迫下苗木根系活力的变化，并研究外源一氧化氮（NO）供体亚硝基铁氰化钠（SNP）对100mmol／L盐碱胁迫下苗木根系活力的影响。结果表明：杂交新美柳在NaCl和Na2SO4胁迫下有一定的应激能力，随着胁迫浓度增加，呈先上升后下降趋势；在NaHCO3和Na2CO3胁迫下根系活力呈下降趋势，且均低于对照。在混合盐碱胁迫下，pH为6．89—7．14时，杂交新美柳的根系活力随胁迫浓度增加呈先上升后下降趋势，当pH〉8．22时，根系活力随胁迫浓度的增高均呈下降趋势。在单盐胁迫下，SNP处理未起到缓解NaCl胁迫的作用，但对Na2SO4、NaHCO3和Na2CO3胁迫均有一定的缓解作用；在混合盐碱胁迫下，随着pH升高，SNP缓解盐胁迫能力逐渐下降，直至消失。

With the materials of Salix hybrid seedlings, the effects of NaCl, Na2SO4 , NaHCO3 , Na2CO3 and complex alkali-saline stress on root activity were studied using completely random blocks design. The effects of sodium nitroprusside （SNP） and the exogenous nitric oxide donor on root activity of Salix hybrid seedlings under salt stress with the concentration of 100 mmol/L were studied too. The results showed that the Salix hybrid had certain stress capacity under NaCl and Na2SO4 stress, when the concentration increased, the root activity declined after rising. Root activity always declined under NaHCO3 and Na2CO3 stress. Under complex alkali-saline stress, the root activity declined after rising with salt concentration increased, when pH value varied from 6.89 to 7. 14. When the pH value was greater than 8.22, root activity declined with the concentration increased. Under single-salt stress, the SNP didn＇ t play a mitigation role in NaCl stress. Under Na2SO4, NaHCO3 and Na2CO3 stress, they all had a certain mitigation. Under complex alkali-saline stress, SNP＇ s mitigation capacity decreased gradually with the pH value increased.