Na_2CO_3胁迫下星星草胁变反应部位的差异

Difference of strain responses between the plant parts of Na_2CO_3 stressed Puccinellia tenuiflora

对砂培星星草用 0～ 175mmol/L的碱性盐Na2 CO3进行了胁迫处理 ,测定了植株不同部位的主要胁变指标 ,比较了各个部位之间对碱性盐胁迫的生理响应差异。结果表明 :在Na2 CO3胁迫下 ,衰老组织中的含水量及氮素水平都明显下降 ,而幼嫩部位则变化很小。植株不同部位的渗透调节作用明显不同 ,趋于衰老的部位以降低含水量和积累无机离子为主特征 ,而代谢旺盛的幼嫩部位则以大量合成并积累有机渗透调节剂为主特征。以柠檬酸为主的有机酸积累与Na+积累相平行 ,而且都主要分布在液泡化程度高的衰老部位 ,其作用可能是中和Na+离子、降低离子毒害及调节细胞内的

The plants of Puccinellia tenuiflora growing in pots filled with sand were stressed with 0～175 mmol/L basic salt(Na 2CO 3). The main strain indexes in the various plant parts were determined. The difference of physiological responses in the different plant parts to the Na 2CO 3?stress was compared. The results showed that under Na 2CO 3?stressed, the water and nitrogen contents in the elder plant parts were obviously decreased and nonsignificantly changed in the younger plant parts. There was a obvious difference between various plant parts in their osmotsic adjustments. For the elder parts, decreasing water content and accumulating inorganic ions were the main means. For the younger parts, accumulating organic osmotic substance was the main mean. The accumulation of organic acid, in which citric acid was dominant, was parallel to Na + content and mainly distributed in the elder parts; its function might be neutralizing Na + and inhibiting ion poisoning and adjusting pH inside cells.