毕业论文模板_理工类.docx

玉林师范学生院本科生毕业论文（设计） PAGE 2 玉林师范学院本科生毕业论文 披碱草属种质资源苗期耐盐性研究 Study on Salt Tolerance of Elymus spp. in Seedling Stage 院 系 化学与生物系 专 业 草业科学 学 生 班 级 2003级2班 姓 名 陈小婷 学 号 200306011005 指导教师单位 化学与生物系 指导教师姓名 苏德荣 指导教师职称 副教授 披碱草属种质资源苗期耐盐性研究 草业科学2003级2班 陈小婷 指导教师 苏德荣 摘要 披碱草属牧草是我国很多草原地区极其重要的牧草资源，具有适应性强，品质优良，产草量高，种子产量高，抗寒耐旱性强的特点，但目前对披碱草属牧草的研究多集中在干旱、寒冷等逆境胁迫研究，而对耐盐性方面的研究很少。本研究以来自全国各地的20份野生披碱草属种质资源为材料，通过不同盐分梯度下各个种质材料在幼苗期的实验研究，对盐胁迫下披碱草属种质材料的株高和分蘖的变化、生物量、存活苗数、叶和根的细胞膜透性、脯氨酸含量等指标进行了系统的测定和分析，研究其耐盐性的差异。通过对材料耐盐性指标的综合评价，筛选出一部份耐盐性强、品质优良的披碱草属种质材料。研究结果如下： 披碱草属种质材料苗期耐盐性研究表明：随着盐浓度的升高，所有材料的株高、分蘖数、生物量、存活率显著降低，但是不同材料的变化范围有所不同。材料根和叶的电解质渗出率随盐浓度的升高而升高。在低盐浓度下，材料电解质渗出率的变化范围不大，随着盐浓度的增加，敏盐材料的电导率大幅上升。材料中游离脯氨酸的含量也随着盐浓度的升高而升高，但是耐盐材料在高盐胁迫下，游离脯氨酸含量上升的幅度较敏盐材料高。通过对披碱草属种质材料苗期耐盐性的综合评价，发现G13、G16、G12属耐盐材料，而G9、G10、G8属敏盐材料，其他属中等耐盐材料。 关键词：披碱草属，耐盐，苗期 Study on Salt Tolerance of Elymus spp. in Seedling Stage Practaculture Science 2003-2 Chen Xiao-ting Supervisor Su De-rong Abstract Elymus L. is one of the most important genus of Poaceae family in many grasslands of China and includes many economically important forage grasses as well as species with agronomically valuable characters, for examples wide adaptation, good feed quality, drought and cold tolerance, and high forage and seed production under stresses. The majority of the research work, however, has been on the cold and/or cold tolerance of Elymus spp, with little attention paid to their salt tolerance. 20 seed samples were collected from natural populations at various locations in China and were cultivated under soilless cultures designed to have different salinity levels (0, 0.4%,0.6%, 0.8% and 1.0% NaCl) and performances of the materials were evaluated in terms of seedling height, tiller number, shoot and root dry weight, plant survival rate, cellular membrance permeability of leaf and root tissues, concentration of free praline. Based on their performances under the salt stresses, materials with high salt tolerance were screened