【作者】 党莉；

【导师】 马恩波；

【作者基本信息】 山西大学 ， 动物学， 2006， 硕士

【摘要】 网翅蝗科(Arcypteridae)是蝗总科的一个大类群,数目多,分布广。蝗灾是一种世界性的生物灾害,自古以来就与水灾、旱灾并称为三大自然灾害。近几年,由于环境恶化等原因,蝗虫危害呈大规模暴发态势,使生态环境遭到严重的破坏,生产力呈不断下降趋势,已威胁到国家生态安全。 随机扩增多态DNA技术(简称RAPD)是二十世纪90年代发展起来的一项DNA分子多态检测技术,它建立在PCR技术基础上,以一系列不同随机排列的碱基序列一单链寡核苷酸为引物一对所研究的基因组DNA进行PCR扩增。该技术能够在没有任何遗传背景的情况下,对物种基因组进行DNA多态性分析。它不但能通过众多的引物检测大量的基因位点,且具有高效、快速、样品用量少和对材料要求不高等优点,目前已广泛应用于动植物的遗传多样性研究中。微卫星引物PCR(SSRP-PCR)技术应用已发表的微卫星核心序列为PCR引物进行扩增(无须知道目的基因的序列),由于引物较长、退火温度更严谨,SSRP-PCR能产生更为稳定和重复的片段,现已经广泛用于研究种内遗传变异,比较种群内和种群间遗传变异。 本文采用随机扩增多态性DNA(RAPD)技术和微卫星引物PCR(SSRP-PCR)技术,研究了我省雏蝗属部分种群的遗传多样性及遗传分化。此外,运用随机扩增多态性DNA(RAPD)技术检测了素色异爪蝗和邱氏异爪蝗的遗传多样性。 用筛选的9条随机引物对雏蝗的9个种群98个个体进行扩增,共获得131个清晰稳定的条带,多态位点共计131个。不同引物在不同种群中所检测出的位点及多态位点百分率不同。Shannon信息指数对数据的分析表明:小翅雏蝗遗传多样性水平较高(0.2542),白纹雏蝗遗传多样性水平较低(0.1911)。Nei’s遗传距离显示,种群间遗传距离小于种间遗传距离。用NJ法对Nei’s遗传距离作聚类分析,构建分子系统树,结果显示:白纹雏蝗与夏氏雏蝗聚为一支,小翅雏蝗与北方雏蝗聚为一支,两支再相聚。聚类图显示了物种间亲缘关系的远近程度与形态分类学结果相一致。更多还原

【Abstract】 The Locust of Arcypteridae is a large insect group of Acridoidea that can be found in various ecological habitats. The insects have different ecotypes and geographic populations as a result of feeding habits and the adaptations to each environment. Due to the extended high temperature, long-lasting drought and the consequent alternations in locust breeding environment, the destructive outbreaks of locust had been increasing in China, which seriously threaten the agriculture production and destroy entironment.The Random Amplified Polymorphic DNA (RAPD) technique is a method for examining the DNA polymorphism developed in 1990s. Based on PCR technology it uses the single-stranded oligonucleotide of random sequence as primer to amplify the genomic DNA. The method is favored because it can examine a large amount of loci at the genome by using many primers. Microsatellite primer PCR analysis (SSRP-PCR) uses published VNTR core sequences as primers in PCR, no prior knowledge of target sequence is required. In addition, studies have indicated that SSRP-PCR can produce more reliable and reproducible bands because of the longer primers and more stringent annealing temperatures. Now it has been applied to examine the variability among species, compare the genetic variation within and among populations.The molecular phylogenetic relationships of four species of Chorthippus Fieber including C. albonemus Cheng et Tu, C. hsiai Cheng et Tu, C. fallaw (Zub.) and C. hammarstroemi (Mir.) were studied with Random amplified polymorphic DNA (RAPD) and Microsatellite primer PCR analysis (SSRP-PCR). Moreover, the genetic divergence of two natural species of Euchorthippus unicoloe (Ikonn) and Euchorthippus cheui Hsia was studied with RAPD method.131 clear and stable bands of 98 grasshopper individuals of Chorthippus with molecular weight ranging from 250 to 1800bp revealed on the electropherogram amplified by 9 primers, Shannon’s index showed hightergenetic diversity (0.2542) within C.fallax (Zub.) and lower genetic diversity (0.1911) within C. albonemus Cheng et Tu. The dendrogram based on Nei’s genetic distance of RAPD and SSRP-PCR markers was constructed with Neighbor-Joining methods. The clustering followed the order, first the individuals within a population, then the different population of the same species, later the species of the same subgenus, and finally the species of the same genus. The four species fell into 2 branches, C. albonemus Cheng et Tu and C. hsiai Cheng et Tu were clustered into one branch, while C. fallax (Zub.) and C. hammarstroemi (Mir.) were grouped to another branch. Then two branches were clustered. The results of dendrogram were consistent with the previous conclusion of morphologic classification.107 clear and stable bands of 29 grasshopper of Euchorthippus individuals revealed on the electropherogram amplified by lOprimers. Nei’s index and a genetic distance matrix were analyzed. The results showed genetic differentiation coefficient estimated by Nei’s index was 0.3839, that is, 61.61% of the variation occurred within species and 38.39% of the variation existed among species. The dendrograms based on Nei’s genetic distance of RAPD markers were constructed using NJ and UPGMA indicating high similarities within species. The results achieved by the method of RAPD revealed the genetic pattern of variation.Comparisons of molecular markers for measuring genetic diversity have been carried out in the way of Genetic relationships. A better understanding of the effectiveness of the different molecular markers is considered a priority step toward locust germplasm characterisation and classification. It is suggested that RAPD and SSRP-PCR analysis is useful as molecular marker, for grasshoppers in phylogenetic reconstruction at the species level.更多还原