盐碱两种胁迫对虎尾草幼苗体内有机调节物质的影响

The Effect of Neutral Salt Stress or Alkali Stress on Organic Matter in Chloris virgata Swartz Seedling

用含盐浓度为60～300 mmo.lL-1的中性盐(NaCl:Na2SO4=1∶1)或碱性盐(NaHCO3:Na2CO3=1∶1)对8周龄砂培虎尾草(Chloris virgataSwartz)进行胁迫处理.通过测定脯氨酸、可溶性糖和甜菜碱的含量来分析虎尾草体内有机渗透调节物质对盐碱两种胁迫的响应特点.结果表明:盐胁迫和碱胁迫均能引起虎尾草体内脯氨酸、可溶性糖和甜菜碱等渗透调节物质的积累,但在积累程度及对渗透调节的贡献方面,两种胁迫之间有所不同.其中盐胁迫和碱胁迫均引起地上部分脯氨酸显著积累,而且,变化趋势基本相同;而地下部分脯氨酸积累的结果则表明,盐胁迫大于碱胁迫,当碱性盐浓度较高时,积累量反而有所降低.无论是地上部分还是地下部分,可溶性糖的积累均表现为随胁迫增加而上升,而且碱胁迫下的增加幅度大于盐胁迫.盐胁迫下,地上和地下部分的甜菜碱含量分别上升了7.4倍和7.7倍;而在碱性盐胁迫下,甜菜碱含量变化不显著.

Eight-week-old plants of puccinellia tenriflora growing in sand filled with vermiculite were stressed by treating with 60 - 300 mmol·L^-1 solutions of neutral salt（NaCl： Na2SO4 = 1 ： 1 ） or alkali salt（ NaHCO3 ： Na2CO3 = 1 ： 1 ） By determining the contents of praline, soluble carbohydrate and beline, characteristics of the responce of organic osmotic adjustment matters in the puccinellia tenriflora what were stressed by salt or alkali stress. The result showed：praline, soluble carbohydrate and beline were all acculated under salt or alkali stress, but the acumulation and contribution to osmotic adjustment werer different between the two stress. But great amount of praline accumulated in the shoot, and the trendecies were alike in the two kinds of stresses. In the mot,the amount of praline under neutral salt-stress was larger than that under alkali stress, the amount of praline decreased when the concentration of alkali salt was high. but The accumulation of the soluble carbohydrate increased in the root and sheet, content of accumulation were increased with rising stress intensity, and the increased range of soluble carbohydrate under alkali stress was more remarkable than that of neutral stress in both of the shoot and mot.. In the neutral salt stress, the content of beline in the shoot and mot were increased respectively times more than CK, but in alkali salt-stress, the conotent of beline had little change.