中文摘要：

本研究目的在于分析甜高粱幼苗在苏打盐碱胁迫下的生理变化,评价甜高粱品种的耐性,比较盐碱胁迫下6个甜高粱品种幼苗生长和生理相关指标的变化。结果表明：盐碱胁迫可降低植株总重量、株高、根长、根系活力和总叶绿素含量;增加可溶性糖、可溶性蛋白和脯氨酸含量;提高过氧化物酶、过氧化氢酶和谷胱甘肽过氧化物酶的活性;同时也增加了质膜相对透性和丙二醛的含量;根冠比和超氧化物歧化酶活性在不同品种间有升有降。其中,品种M-81E根长下降最小,根冠比增加最大,质膜相对透性和丙二醛含量增加最小,超氧化物歧化酶和过氧化氢酶活性增加最多;而314B则根冠比、株高和叶绿素含量均下降最多,膜相对透性和丙二醛含量增加较多。隶属函数法对各品种耐性评价表明,各品种耐盐碱性由强到弱的综合排序为：M-81E〉Rio〉西蒙〉能饲一号〉科特尔〉314B。研究表明,根冠比增加,根系活力下降小,可溶性蛋白增加多,超氧化物歧化酶活性增加,过氧化氢酶活性增加量大是耐盐碱胁迫甜高粱品种的主要适应性特征。

英文摘要：

In order to study the physiological changes to the saline-sodic stress based on the composition of Na2CO3 and NaHCO3 and assess the tolerance of different varieties of sweet sorghum（Sorghum bicolor（Linn.） Moench）,the paper was determined the relative indexes of seedling growth and physiology in the six varieties of sweet sorghum seedlings with condition of salin-sodic stress.The results showed that compared with the respective control group,under saline-sodic stress,the sweet sorghum seedlings was decreased the total weight of plant,height,root vigor and total chlorophyll content,but increased the content of soluble sugar,soluble protein and proline,improved the activity of peroxidase,catalase and glutathione peroxidase.Meanwhile,plants were increased the relative permeability of plasma membranes and content of malonaldehyde.However,rootshoot ratio and activity of superoxide dismutase were showed higher or lower among the different varieties.M-81E displayed that root length was down slightly, root-shoot ratio was increased furthest,the relative permeability of plasma membranes and content of malonaldehyde were added least,superoxide dismutase and catalase were enhanced furthest.But,314B displayed that root-shoot ratio,height and total chlorophyll content were decreased most,the relative permeability of plasma membranes and content of malonaldehyde were added more.The assessment of the sweet sorghum tolerance to saline-sodic stress with the method of subordinate function values showed that the 6-varieties of sweet sorghum were ordered in sequence from the strong to weak： M-81EXimengRioNengsiⅠKeteer314B.The conclusions can reflect that the main adaptable characterizations from sweet sorghum seedlings resisting the condition of saline-sodic stress,were the root-shoot ratio increased,the root vigor decreased lesser,the content of soluble protein increased more,the activity of superoxide dismutase and catalase increased more.