›› 2018, Vol. 61 ›› Issue (9): 1054-1066.doi: 10.16380/j.kcxb.2018.09.007

• 研究论文 • 上一篇    下一篇

中国东北地区亚洲玉米螟遗传多样性及寄主专化性分析

王克勤*, 刘兴龙, 邵天玉   

  1.  (黑龙江省农业科学院植物保护研究所, 哈尔滨 150086)
  • 出版日期:2018-09-20 发布日期:2018-09-20

Analysis of the genetic diversity and host specialization of Ostrinia furnacalis (Lepidoptera: Crambidae) in Northeast China

WANG Ke-Qin*, LIU Xing-Long, SHAO Tian-Yu   

  1.  (Institute of Plant Protection, Heilongjiang Academy of Agricultural Sciences, Harbin 150086, China)
  • Online:2018-09-20 Published:2018-09-20

摘要: 【目的】为了明确中国东北地区亚洲玉米螟Ostrinia furnacalis不同地理种群、不同田间寄主种群间的遗传分化程度和基因流水平,了解不同种群间是否产生寄主专化性和遗传结构的差异。【方法】采用双向测序法测定了采自中国东北3种主要寄主植物(玉米Zea mays、高粱Sorghum bicolor和谷子Setaria italica)上的23个地理种群400头亚洲玉米螟个体的线粒体细胞色素氧化酶亚基I (COI)基因的1 034 bp序列;利用DnaSP 5.0和Arlequin3.5.1.2等软件对亚洲玉米螟不同寄主种群以及不同地理种群间的遗传多样性、基因流水平、系统进化发育和分子变异进行分析。【结果】共获得400条长度为1 034 bp的亚洲玉米螟线粒体COI基因序列,包含60个单倍型。亚洲玉米螟总群体的单倍型多样度(Hd)为0.793±0.01,不同地理种群间的单倍型多样度范围在0~0.916±0.041之间。总基因交流水平较高(Nm=2.67),总的群体Fst为0.1579,不同地理种群的Fst范围在-0.046~0.627之间。总种群的Tajima’s D为-1.73602,检验结果不显著,说明中国东北地区亚洲玉米螟未曾在近期经历种群扩张,群体大小稳定。AMOVA分子变异分析结果表明,不同地理种群间的遗传分化较大(Fst=0.16236, P<0.0001),83.76%遗传变异主要来自种群内部,而种群间的遗传变异仅为16.24%,不同寄主种群间的遗传分化(Fct=0.01568, P>0.05)很小,遗传变异仅占1.57%,说明亚洲玉米螟的遗传分化主要来自种群内部,而非其地理种群间或寄主种群间。各寄主种群的单倍型在系统发育树上和中介网络图上散布在不同种群中,缺乏明显的地理分布和寄主分布格局。【结论】亚洲玉米螟较强的迁飞能力(或随气流进行远距离传播),使各种群间的基因交流未受到地理距离的影响,遗传距离与地理距离之间没有显著相关性。虽其寄主范围较广,但取食不同寄主植物的亚洲玉米螟种群间基因交流频繁,以玉米、高粱和谷子为寄主的种群尚未产生寄主专化性和种群遗传结构的差异。

关键词: 亚洲玉米螟, 线粒体COI基因, 寄主, 地理种群, 遗传多样性, 基因流

Abstract: 【Aim】 This study aims to identify the degree of genetic differentiation and gene flow level among different geographic populations and host populations of Ostrinia furnacalis in Northeast China, and to clarify whether there is a host specialization and genetic structural change between different populations. 【Methods】 A 1 034-bp segment of the mitochondrial cytochrome c oxidase subunit I (COI) gene of 400 individuals from 23 geographic populations of O. furnacalis on three main host plants [corn (Zea mays), sorghum (Sorghum bicolor) and millet (Setaria italica)] in Northeast China was sequenced and analyzed by bidirectional sequencing. The genetic diversity, gene flow level, phyletic evolution and molecular variance among different host populations and different geographic populations of O.furnacalis were analyzed using DnaSP 5.0 and Arlequin3.5.1.2. 【Results】 A total of 400 COI gene sequences of 1 034 bp, including 60 haplotypes, were obtained from O. furnacalis. The total haplotype diversity (Hd) of all populations was 0.793±0.01, and the range of haplotype diversity of different geographic populations was 0-0.916±0.041. The level of total gene flow was high (Nm=2.67), the total Fst of the total population was 0.1579, and the range of Fst of different geographic populations was -0.046-0.627. Tajima’s D of the total population was -1.73602, and the test results were not significant, suggesting that the O. furnacalis in Northeast China has not experienced the recent expansion of population, and the population size is stable. Molecular variance analysis (AMOVA) demonstrated that the genetic differentiation between different geographic populations was great (Fst=0.16236, P<0.0001), and 83.76% of genetic variation was mainly within a population, while the genetic variation between populations was only 16.24%. The genetic differentiation between O. furnacalis populations on different hosts (Fct=0.01568, P>0.05) was small, and the genetic variation accounted for only 1.57%, suggesting that the observed genetic differentiation of O.furnacalis occurs primarily within populations, and there is no obvious genetic differentiation among its geographic populations and host populations. The neighbor-joining phylogenetic tree and haplotype network showed that the haplotypes of host populations were distributed in different populations, and no obvious geographic distribution and host distribution patterns were found. 【Conclusion】 Due to the stronger flight ability (or spreading long distances with air) of O. furnacalis, the gene flow is not affected by geographic distance, and the genetic distance is not significantly correlated with the geographic distance. Despite of the wide host range of this insect, the gene flow is frequent among its different host populations, and host specialization and genetic structural difference don’t exist among host populations collected from corn, sorghum and millet.

Key words: Ostrinia furnacalis; mtDNA COI gene, host, geographic population, genetic diversity, gene flow