【作者】 兰小中；

【导师】 郑维列；

【作者基本信息】 西藏大学 ， 生态学， 2008， 硕士

【摘要】 本文以色季拉山的高寒植物垫状雪灵芝为材料,选取分布在海拔4500-4650m范围内的垫状雪灵芝3个居群为研究对象,采用聚丙烯酰胺琼脂电泳技术,对垫状雪灵芝3个居群的48个个体功能叶片的过氧化物酶、细胞色素氧化酶、乙醇脱氢酶、酯酶等同工酶谱带进行测定并编码,依据酶谱带测定结果进行聚类分析;同时结合过氧化物酶、细胞色素氧化酶、乙醇脱氢酶和酯酶等四种同工酶的3个遗传指标进行相关分析。结果表明:1过氧化物酶同工酶来自同一居群的个体,不但同工酶谱带相似性高,遗传杂合度小(HeA=0.716;HeB=0.709;HeC=0.705),特别是居群B、C相似性系数大,遗传距离小,这也说明居群内个体遗传分化小;过氧化物酶在不同居群间的相似性系数在四种同工酶中的平均值相对较大,遗传距离相对较小(IAB=0.637;IAC=0.587;IBC=0.646;DAB=0.451;DAC=0.533;DBC=0.437)。这些数据表明垫状雪灵芝过氧化物酶同工酶在不同的居群之间存在一定程度的遗传分化,缺少有效的基因交流。2细胞色素氧化酶同工酶垫状雪灵芝的细胞色素氧化酶同工酶在居群内的个体,同工酶谱相似性较高,遗传杂合度比过氧化物酶同工酶较高(HeA=0.752;HeB=0.815;HeC=0.815),在居群A、B、C中基因频率在0.50以上的谱带相对较多,其中A、B居群中各有6条,C居群中有5条,最高值可达到0.94,遗传距离小,这也说明居群内个体遗传分化小;细胞色素氧化酶在不同居群间的相似性系数有最大值和整个种群中四种同工酶的最小值,遗传距离也是如此(IAB=0.418;IAC=0.304;IBC=0.673;DAB=0.873;DAC=1.192;DBC=0.396)。遗传距离最大值是DAC=1.192;这些数据表明垫状雪灵芝细胞色素氧化酶同工酶在不同的居群之间存在较大的遗传分化。3乙醇脱氢酶同工酶垫状雪灵芝的乙醇脱氢酶同工酶在居群内的个体,同工酶谱相似性较高,遗传杂合度比细胞色素氧化酶同工酶较小(HeA=0.766;HeB=0.872;HeC=0.736),在居群A、B、C中基因频率在0.50以上的谱带相对较多,其中A居群中有7条,最高值为1.00,B居群中有3条,最高值为1.00,C居群中有7条,最高值为0.88,遗传距离小,这也说明居群内个体遗传分化小,具有高度的遗传同质性;乙醇脱氢酶在不同居群间的相似性系数均较小,而遗传距离相对较大(IAB=0.539;IAC=0.367;IBC=0.513;DAB=0.618;DAC=1.002;DBC=0.667)。遗传距离最大值是DAC=1.002;这些数据表明垫状雪灵芝乙醇脱氢酶同工酶在不同的居群之间存在较大的遗传分化。4酯酶同工酶垫状雪灵芝的酯酶同工酶在居群内的个体,同工酶谱相似性极高,遗传杂合度在四种同工酶中是最低的(HeA=0.735;HeB=0.765;HeC=0.726),在居群A、B、C中基因频率在0.50以上的谱带相对较多,其中A居群中各有10条,B、C居群中各有8条,最高值均可达到0.90以上,并且C居群中基因频率为1.00的谱带有3条,居群内个体遗传距离小,这也说明居群内个体遗传分化小;然而,酯酶在不同居群间的相似性系数有不同程度的变化,遗传距离也是如此(IAB=0.392;IAC=0.542;IBC=0.610;DAB=0.937;DAC=0.613;DBC=0.495)。遗传距离最大值是DAB=0.937;这些数据表明垫状雪灵芝酯酶同工酶在不同的居群之间存在较大的遗传分化。四种同工酶无论是在遗传系数,还是同工酶谱或聚类方面表现出的变化趋势和幅度并不完全一致,这些表明垫状雪灵芝在长期进化的过程中,控制各种同工酶的不同基因并没有协同进化,这种现象在自然界是普遍存在的。青藏高原特殊的气候条件和垫状雪灵芝的地理分布格局所造成的,形成了垫状雪灵芝的同工酶变异特点。更多还原

【Abstract】 In this paper, the alpine plant Arenaria pulvinata Edgew. of Sejila Mount is used as the material, selecting three populations of Arenaria pulvinata Edgew. distributing the elevation of 4500-4650m for research. The technology of Polyacrylamide agar electrophoresis is used to determine and code the bands of isozyme such as Peroxidase, Cytochrome oxidase, Alcohol dehydrogenase, Esterase and so on , which are from the 48 individual functional leaves of three populations of Arenaria pulvinata Edgew. and then according to the results of the enzymatic bands, we do cluster analysis. At the same time, with three genetic indicators of the four isozymes , Peroxidase, Cytochrome oxidase, Alcohol dehydrogenase, and Esterase, correlation analysis is done. The results indicate:1.Peroxidase IsozymesFrom the same populations of the individual, not only similarity of isozyme bands, small genetic heterozygosity (HeA=0.716;HeB=0.709;HeC=0.705), particularly the coefficient of similarity is larger and genetic distance is small in populations of B, C,This also shows that the individual’s genetic differentiation in populations smaller enough. The Peroxidase, which coefficient of similarity’s average of four isozyme is relatively bigger in different populations and genetic distance is small(IAB=0.637;IAC=0.587;IBC=0.646;DAB=0.451;DAC=0.533;DBC=0.437),These data indicate that the peroxidase isozyme of Arenaria pulvinata Edgew. being certain degree of genetic differentiation in different populations, and also lack of effective gene flow.2. Cytochrome oxidase isozymesThe cytochrome oxidase isozymes of Arenaria pulvinata Edgew. in the populations of the individual, which isozyme bands is similar, and the genetic heterozygosity is higher than peroxidase (HeA=0.752;HeB=0.815;HeC=0.815), The bands of gene frequency above 0.50 is relatively more than others in the populations of A,B,C, and there is 6 bands in populations of A, B, each other ,and there is 5 bands in populations of C, its maximum value could reach 0.94, and the genetic distance is small, it also shows that populations of genetic differentiation within the individual is small; The coefficient of similarity of cytochrome oxidase being the maximum in different populations and a factor in the entire population of the four types of isozyme minimum, the same is true of genetic distance (IAB=0.418;IAC=0.304;IBC=0.673;DAB=0.873;DAC=1.192;DBC=0.396). The maximum of genetic distance is DAC = 1.192; These data shows that the cytochrome oxidase Isozymes of Arenaria pulvinata Edgew. being larger genetic differentiation in different populations.3. Alcohol dehydrogenase isozymesThe alcohol dehydrogenase isozymes of Arenaria pulvinata Edgew. in the populations of the individual, which isozyme bands is similar, and the genetic heterozygosity is lower than cytochrome oxidase isozymes (HeA=0.766;HeB=0.872;HeC=0.736), The bands of gene frequency above 0.50 is relatively more than others in the populations of A,B,C, and there is 7 bands in populations of A, its maximum reach to 1.00, there is 3 bands in populations of B, its maximum reach to 1.00 too, there is 7 bands in populations of C ,its maximum reach to 0.88, but its genetic distance is small, it also shows that populations of genetic differentiation within the individual is small, with a high degree of genetic homogeneity。The coefficient of similarity of Alcohol dehydrogenase are smaller and relatively larger genetic distance in different populations (IAB=0.539;IAC=0.367;IBC=0.513;DAB=0.618;DAC=1.002;DBC=0.667). The maximum of genetic distance is DAC = 1.002; These data show that the alcohol dehydrogenase Isozymes of Arenaria pulvinata Edgew. being larger genetic differentiation in different populations.4. Esterase IsozymesThe Esterase isozyme of Arenaria pulvinata Edgew. in the populations of the individual, which isozyme spectrum is similar, and the genetic heterozygosity is lowest in these four isozyme. (HeA=0.735;HeB=0.765;HeC=0.726), The bands of gene frequency above 0.50 is relatively more than others in the populations of A,B,C , and there is 10 bands in population of A ,there is 8 bands in population of B , C each other, and the maximum could reach to 0.99, furthermore, there is 3 bands ,which gene frequency is 1.00 and the genetic distance is small, it also shows that populations of genetic differentiation within the individual is small; However, the coefficient of similarity of EST isozyme have different degrees of change in different populations, and the gentic distanceis so (IAB=0.392;IAC=0.542;IBC=0.610;DAB=0.937;DAC=0.613;DBC=0.495). The maximum of genetic distance is DAB = 0.937; These data show that the EST isozyme of Arenaria pulvinata Edgew. being larger genetic differentiation in different populations. The shown on changes in trends and ranges of the four isozymes is not exactly simility, whether in the genetic factors or the isoenzymatic patterns or the clustering, which shows in the process of long-term evolution of Arenaria pulvinata Edgew.,the different genes which control kinds of isozymes have no co-evolution. This phenomenon is widespread in nature. Because of the special climatic conditions of Qinghai- Tibet Plateau and the geographical distribution pattern of Arenaria pulvinata Edgew., the variant characteristics of isozymes of Arenaria pulvinata Edgew. are formed.更多还原