论文部分内容阅读
【目的】通过对四纹豆象Callosobruchus maculatus Fabricius不同地理种群mtDNA-Cytb和COⅠ基因部分序列进行比较,分析其不同地理种群间的遗传分化情况,为揭示其与生物入侵的关系及入侵过程中种群系统发育地理格局与演变机制提供依据。【方法】用PCR产物直接测序法对分别来自中国海南、喀麦隆、韩国和泰国的四纹豆象4个地理种群的mtDNA-Cytb和COⅠ序列进行测序,运用软件MEGA3.1对四纹豆象不同地理种群mtDNA-Cytb和COⅠ序列进行序列分析,以绿豆象C.chinensis为外群构建了不同单倍型的分子系统树。【结果】34条420bpCytb序列中共检测到14个多态位点和5种单倍型,33条822bpCOⅠ序列中检测到28个多态位点和9种单倍型,其中4种单倍型为独享单倍型,其余为全部或部分种群的共享单倍型。AMOVA分析结果显示,四纹豆象4个地理种群间的遗传结构差异并不明显,遗传差异主要发生在地理种群内。对4个地理种群进行了Fst值和基因流动统计,结果表明4个地理种群间既存在着一定数量的基因交流,也存在一定程度的遗传分化。【结论】根据单倍型分布格局初步推测,中国不可能是四纹豆象的原产地,而喀麦隆有可能是原产地之一,并且喀麦隆种群与泰国种群之间的基因交流比较充分,而中国种群与其他种群之间的遗传分化相对较大。
【Objective】 The genetic diversity of mtDNA-Cytb and COⅠ gene in different geographic populations of Callosobruchus maculatus Fabricius was compared and the genetic differentiation among different geographical populations was analyzed. In order to reveal its relationship with biological invasion and population during invasion Phylogeography and evolution mechanism provide the basis for geographical development. 【Method】 The mtDNA-Cytb and COⅠ sequences of four geographical populations of Siberian asteroids from Hainan, Cameroon, South Korea and Thailand were sequenced by direct sequencing of PCR products. The software MEGA3.1 Sequence analysis of the mtDNA-Cytb and COⅠgenetic populations showed that the molecular phylogenetic tree with different haplotypes was constructed from C.chinensis. 【Result】 Totally 14 polymorphic loci and 5 haplotypes were detected in 34 sequences of 420bpCytb, 28 polymorphic sites and 9 haplotypes were detected in 33 822 bp COⅠ sequences, of which 4 haplotypes were Exclusive haplotypes, the rest being shared haplotypes of all or part of the population. The results of AMOVA analysis showed that the genetic structure differences among four geographical populations of Sianguangxiang were not obvious, and the genetic differences mainly occurred within the geographical populations. Fst values and gene flow statistics of four geographical populations were conducted. The results showed that there existed a certain number of gene exchange and genetic differentiation among the four geographic populations. 【Conclusion】 According to the haplotype distribution pattern, it is preliminarily speculated that China could not be the country of origin of Camellia sinensis, Cameroon may be one of the countries of origin, and the gene exchange between Cameroonian population and Thai population is more sufficient. However, Genetic differentiation between populations and other populations is relatively large.