【作者】 卢素锦；

【导师】 周青平； 颜红波；

【作者基本信息】 青海大学 ， 草业科学， 2008， 硕士

【摘要】 本研究对同德小花碱茅[Puccinellia tenuiflora（Griseb.）Scribn.&Merr,cv Tongde]种子萌发期和幼苗期进行盐碱胁迫,得出的主要结论如下:1.在Na₂CO₃胁迫下同德小花碱茅种子的发芽率、发芽指数、活力指数、幼苗生长势与Na₂CO₃胁迫浓度呈现出极其显著的负相关关系。影响同德小花碱茅种子累积发芽率的Na₂CO₃浓度的适宜值、临界值、极限值分别为1.42%,2.62%,3.94%,当Na₂CO₃浓度大于6.00%时,种子不再萌发。清水复萌实验表明,经较高浓度Na₂CO₃处理的种子仍具有较高的发芽潜能。2.同德小花碱茅种子的吸水量随着Na₂CO₃浓度增高而逐渐降低。但不同阶段吸水量随着Na₂CO₃浓度的上升而下降的幅度不同。Na₂CO₃胁迫下,同德小花碱茅种子的膜系统修复受阻,Na₂CO₃浓度与膜透性正相关极其显著。膜透性与发芽率之间也呈极其显著的负相关关系,这表明膜修复受阻是Na₂CO₃胁迫抑制同德小花碱茅种子萌发的重要原因之一。3.在Na₂CO₃胁迫下,同德小花碱茅种子萌发过程中淀粉酶活性、可溶性糖含量、呼吸强度与空白对照相比均下降,当Na₂CO₃浓度大于5.00%时,同德小花碱茅种子在播种后至测量结束时,淀粉酶活性、可溶性糖含量、呼吸强度几乎都没有变化,三者与Na₂CO₃胁迫浓度的负相关关系均极其显著。水解酶活性降低、储藏物质不能动员导致其不能水解、呼吸代谢受抑制是Na₂CO₃胁迫下同德小花碱茅种子萌发受抑制的主要原因。4.用不同浓度的Na₂CO₃溶液和不同浓度的混合盐溶液处理同德小花碱茅幼苗,6d后测定叶片相对电导率、光合速率（Pn）、气孔导度（Gs）、胞间CO₂浓度（Ci）、蒸腾强度（Tr）、水分利用效率（WUE）、可溶性糖含量和脯氨酸含量等生理指标,结果表明,低浓度盐碱胁迫下,同德小花碱茅具有一定的耐盐光合蒸腾特性和较强的渗透调节能力。更多还原

【Abstract】 The reseach of Puccinellia tenuiflora（Griseb.）Scribn.&Merr,cv Tongde P seeds and seedings under sodium carbonate stress were studied. the main conclusion was gained as follows:1. Germination percentage, germination index, vigor index and growth potential of Puccinellia tenuiflora（Griseb.）Scribn.&Merr,cv Tongde seeds have the significant negative correlation to the stressing concentration of sodium carbonate solution .The proper ,critical ,and limit value of sodium carbonate concentration that affects germination percentage is 1.42%,2.62% and 3.94% respectively. Seeds that could not germination in sodium carbonate solution germinated again in distilled water. The result showed that seeds stressed in higher concentration of sodium carbonate solution still have greater germination capacity showing the especially stronger resistance of Puccinellia tenuiflora（Griseb.） Scribn.&Merr,cv Tongde to salt alkali.2. The amount of water absorbed decreased gradually along with the increasing concentration of sodium carbonate solution. But the amount decreased was different along with the increasing concentration of sodium carbonate solution in different phases. The membrane permeability had the significant positive correlation to the sodium carbonate concentration. Moreover, the significant negative correlation between membrane permeability and germination percentage indicated that inhibition of membrane restoration was an important reason that inhibited germination under the stress of sodium carbonate.3. Diastase activity, soluble carbohydrate content, respiration intensity had a positive correlation with germinating process in salt free condition. When the sodium carbonate concentration was more than 5.00%, changes of diastase activity, soluble carbohydrate content and respiratory intensity of germinating Puccinellia tenuiflora（Griseb.）Scribn.&Merr,cv Tongde seeds nearly did not happen, but it had a significant negative correlation with each other. The decrease of hydrolytic enzyme activity and inhibition of the using of storing material and the inhibition of respiration were the main reasons the Puccinellia tenuiflora（Griseb.）Scribn.&Merr,cv Tongde seeds could not germinate under sodium carbonate stress.4. Puccinellia tenuiflora（Griseb.）Scribn.&Merr,cv Tongde seedlings were rreated with with Na₂CO₃ at different concentrations and were rreated with mix-salt stress at different concentrations.The results showed that treated with salt stress at lower concentrations, Puccinellia tenuiflora could alleviate its cellular injury through osmotic regulation, so that the membrane permeability slightly suffered.更多还原