【作者】 姚邦威；

【导师】 褚建君；

【作者基本信息】 上海交通大学 ， 生物化学与分子生物学， 2011， 硕士

【摘要】 本文以华东地区(安徽省、江西省、江苏省、山东省、浙江省和上海市)的麦田和油菜田优势种杂草菵草为研究对象,选取12种生态型研究其生长特性、光合特性、结实特性、抗逆特性及营养学特性,采用ISSR分子标记技术研究了遗传多样性,并测定了不同生态型的Actin基因序列。研究发现,不同生态型菵草的种群增长均符合Logistic生长曲线,在叶龄、株高、千粒重方面差异较小,但种群增长速度、种群饱和值、平均穗长和穗重差异较大;来源于同一地区的不同生态型相比较,采集于非耕地的生态型分蘖能力更强,而且光合作用光能转换效率(以PSⅡ最大光化学量子产量计)均高于采集于麦田或油菜田的生态型;来源于不同地区的生态型之间,与耐寒能力相关的超氧化物歧化酶(SOD)活性具有显著性差异,而且与纬度相关。本文系统测定了不同生态型菵草种子的总糖、可溶性糖、还原糖、粗蛋白、游离氨基酸以及脂溶性成分的含量,利用液相色谱、气质联用等方法定量测定了氨基酸和脂溶性成分的种类及含量。发现不同生态型菵草的种子脂溶性物质含量高于小麦、玉米等常见饲料原料,并含有D-α-生育酚、菜籽甾醇、芸苔甾醇、β-谷甾醇等重要的动物饲料添加剂成分,可作为精饲料加工利用;而且不同生态型种子所含营养成分的种类及含量均无显著差异,表明不同菵草生态型种子的品质是稳定的。本文选取12个生态型共48个样品应用ISSR分子标记技术研究不同生态型的遗传多样性,用筛选出的9条引物进行PCR扩增,共扩增出51条重复性高、清晰的条带,扩增片断分子量从200 bp至2200 bp不等,平均每条引物扩增出5.6条条带,其中多态性条带为43条,有效条带百分率(P)84.31%。在物种水平上,菵草基因多样性指数(H)为0.193,Shannon多样性指数(I)为0.3761,遗传分化系数(GST)为0.214,基因流(Nm)为0.5107。实验结果发现了与生态型密切相关的特异性条带,而且不同生态型之间遗传距离UPGMA结果与地理分布相关性较高。结果表明,用ISSR引物进行PCR扩增可以清晰、有效地分辨出每个样品的基因型,说明ISSR标记适用于菵草的遗传多样性研究。本文还测定了12个生态型共12个样品的Actin基因序列(登录号JF411409-JF411420),不同生态型的Actin基因同源性为97%~99%,Blast比较发现GENE BANK数据库中尚无Beckmannia属植物Actin基因序列,Actin序列与Beckmannia syzigachne最为接近的物种是Avena nuda(登录号AF234528),MEGA 4作系统进化树发现不同生态型之间系统发育关系与地理分布相关性较高。更多还原

【Abstract】 In this study, we chosed 12 different ecotypes of Beckmannia syzigachne that is dominant population of the weed communities in wheat and rape field of East China and investigated their growth, photosynthetic, fruiting, adverse-resistant, and nutritional characteristics. The Actin gene of 12 different Ecotypes of Beckmannia syzigachnes were sequenced and the ISSR was used to examine the genetic diversity.The results show that the population growth of 12 different ecotypes of Beckmannia syzigachne fits the Logistic growth curve and there is little differences in the characteristics of leaf age, plant hight and 1000-grain weight but great difference in the characteristics of the average panicle length, population growth speed, population saturation value and panicle weight. Compared with the different ecotypes of Beckmannia syzigachne originated from the same region, the Beckmannia syzigachne from untilled land is stronger in tillering ability and higher in the conversion efficiency of photosynthesis than these from wheat and rape field. The activity of superoxide dismutase of these ecotypes of Beckmannia syzigachne from different regions is significant different and correlates with latitude. The activity of superoxide dismutase relates with the cold-resistant capacity.In this paper, we studied the contents of total sugar, soluble sugar, reducing sugar, crude protein, free amino acid and fat-soluble components of Beckmannia syzigachne seeds of different ecotypes, and HPLC, GC-MS were used to determine the types and composition of amino acid and fat-soluble components. The results show that the contents of fat-soluble components in all the Beckmannia syzigachne seeds are higher than those in common feed ingredients like wheat and maize. In addition, the important components , such as D-α-tocopherol, brassicasterol, campesterol,β-Sitosterol, etc have been identified in the seeds which makes them enable to be used as concentrated feed; what`s more, the types and contents of nutritional components in the seeds from different locations show no significant diversity, indicating the conservation of seed quality of different ecotypes.In this study, We sampled 48 individuals from 12 different ecotypes Beckmannia syzigachne and ISSR was applied to investigate the genetic diversity of different ecotypes Beckmannia syzigachne. Nine primers were selected for PCR and produced 51 bands, of which 43 (P=84.31%)were polymorphic. The average number of bands per primer was 5.6 and the size of the amplified DNA fragments ranged from 200 bp to 2200 bp. At species level, the gene diversity(H) of Beckmannia syzigachne was 0.193, Shannon Index of diversity(I)is 0.3761, Genetic differentiation(GST) is 0.214 and gene flow(Nm) is 0.5107. In experiments specific bands were found to have close relationship with the ecotype and the UPGMA dendrogram based on genetic distances among different ecotypes has high corelation with the geographic distribution. The observation exhibited that using ISSR primer for PCR can produce effective amplified DNA fragments to determine each genotype and suugested that ISSR is an effective approach to investigate the genetic diversity of Beckmannia syzigachne.Besides, we sequenced the Actin gene of 12 ecotypes Beckmannia syzigachne(accession no. JF411409- JF411420), and the the Actin genes of different ecotypes shared 97-98% identity. BLAST alignment found there was no sequence of Beckmannia Host. in GENE BANK and the most similar in Actin with Beckmannia syzigachne is Avena nuda(accession no. AF234528). We applied MEGA 4 to make Phylogenetic tree and found the phylogenetic relationships of different ecotypes Beckmannia syzigachne have high corelation with the geographic distribution.更多还原