氯化钠对白木香离体根生长、生理和化学成分的影响

Effects of NaCl Stress on Growth,Physiology and Chemical Constituents of Aquilaria Sinensis in Vitro Roots

目的以白木香离体根为材料,研究NaCl浓度及处理时间对白木香离体根的生长、生理和化学成分的影响,为白木香耐盐性研究提供参考。方法通过次代根的生根率、侧根条数、侧根根长和侧根直径考察盐胁迫对白木香离体根生长的影响,通过脯氨酸和抗氧化酶含量考察盐胁迫下的生理变化,利用GC-MS分析不同盐处理下化学成分的变化情况。结果随NaCl浓度的增加,次代根的生根率和侧根条数下降,侧根直径和侧根根长呈增加趋势。脯氨酸含量随处理浓度的增加先增后降,抗氧化酶含量在低浓度时随处理时间增加而升高,中高浓度时则呈现先增后降的趋势。化学成分分析显示,与对照组相比,处理组产生了6种新物质。结论低浓度NaCl处理能促进白木香离体根侧根的生长,使脯氨酸和抗氧化酶的含量升高并产生新的化合物;高浓度NaCl严重影响离体根的再生。

Objective In vitro roots of Aquilaria sinensis were chosen to study the growth,physiology and chemicalcomposition under salt stress caused by different NaCl concentration with various duration time. It was expected toprovide reference for study of the salt tolerance of Aquilaria sinensis. Methods The effects of salt stress on thegrowth of Aquilaria sinensis in vitro roots were investigated using rooting rate,length,and root diameter of lateralroots as indicators. The physiological changes under salt stress were quantified by the content of proline andantioxidant enzymes＇ activities. And GC-MS was used to analyze the production of chromones under different stressconditions. Results From the aspect of growth of the next generation roots,the number of lateral roots decreasedwith the increase of salt stress,and the length and diameter of lateral roots increased. The activities of antioxidantenzymes and content of proline increased first and then decreased with the increase of salt concentration. However,two chromones were detected in low concentration NaCl stressed roots. Conclusion NaCl stress at low concentrationpromoted the growth of lateral roots,increased the contents of proline and antioxidant enzymes,and also stimulated the roots producing new compounds. NaCl stress with high concentration destroyed the regeneration of in vitro roots.