| 摘要: |
| 本研究选取2011年采自河南烟区的32个菌株, 根据4个核基因(包括rDNA ITS、β-tubulin、Ras和Gpi基因)和1个线粒体基因(Cox1)的保守序列, 克隆和测序分析160个相应的基因DNA片段。结果显示, 这5个基因DNA序列在病菌群体内碱基序列与参照基因序列相比保守度在83%~100%不等, 平均基因型多样性指数(M)为1.422 7。综合使用5个基因联合序列联合构建群体进化系统树, 揭示了分布于河南省14个县区的32个分离菌系可分为2个明显的组, 包括15个不同的联合基因型, 基因型多样性指数为2.35, 反映了病菌致病变种内存在的遗传变异多样性。其中, 最优势的2个联合基因型分别涵盖8个c基因型菌系和6个e基因型菌系。然而, 各基因型间遗传分化的总水平很低, 组间的遗传距离仅为0.000 5, 说明烟草黑胫病菌在河南生长烟草中的菌株可能属于同一有效群体。同时, 不同分化菌株遗传亲缘关系与地理来源之间也没有显著的相关性, 表明烟草黑胫病菌河南群体内存在密切的菌源交流, 没有形成明显的地理亚群体分化。本研究结果可广泛应用于大规模黑胫病菌群体菌系的动态检测, 服务于烟草抗黑胫病育种和品种合理布局。 |
| 关键词: 烟草黑胫病菌 遗传多样性 系统进化 核基因 线粒体基因 序列分析 |
| DOI：10.11841/j.issn.1007-4333.2014.06.03 |
| 投稿时间：2014-03-22 |
| 基金项目:河南省烟草公司科技专项(201111);国家烟草专卖局重点项目(110200902065) |
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| Population genetic diversity of Phytophthora parasitica var.nicotianae in Henan province of China revealed by nuclear and mitochondrial DNA sequencing |
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FENG Song-li1, JIANG Shi-jun2, SONG Peng-yu1, WANG Hai-tao3, XING Guo-zhen1, KANG Ye-bin4, LI Shu-jun3, ZHENG Wen-ming1
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| (1.College of Life Sciences, Henan Agricultural University, Zhengzhou 450002, China;2.College of Plant Protection, Henan Agricultural University, Zhengzhou 450002, China;3.Tobacco research Institute, Tobacco company of Henan Province, Xuchang 461000, China;4.College of Forestry, Henan University of Science and Technology, Luoyang 471003, China) |
| Abstract: |
| Tobacco Black Shank is a kind of worldwide-occurred tobacco diseases, caused by Phytophthora parasitica var. nicotianae (Breda de Haan) TucKer , and widely distributed in the tobacco-planting areas of China.Tobacco-growing areas in Henan province are always heavily threatened and severely impaired by this pathogen, a deeper understanding of the population genetic structure of Tobacco Black Shank is very important for effective prevention and controlling of this disease.In this study, 32 strains from Henan tobacco-growing areas had been collected in 2011, and 160 corresponding DNA fragments had been cloned, and sequenced for 4 nuclear genes (including rDNA ITS, β-tubulin, Ras and Gpi) and 1 mitochondrial gene(Cox1).The results indicated that there was a high similarity between these 5 gene DNA sequences of this pathogen and corresponding reference DNA sequences, which were from 83% to 100%, the average genotype diversity index M=1.422 7.Population evolution phylogenetic tree was established by using combined sequences of all 5 genes, revealing that 32 isolated strains from 14 counties of Henan could be divided into 2 clear clusters, including 15 different combined genotypes with genotype diversity index=2.35, reflecting the variation and high genetic diversity in Phytophthora parasitica var.nicotianae (Breda de Haan) TucKer.Among them, two most prevalent combined genotypes included 8 strains(c genotype) and 6 strains(e genotype), respectively.However, the total level of genetic differentiation between these genotypes was low, genetic distance between clusters was merely 0.000 5, demonstrating that Henan strains might belong to same effective population.On the other hand, genetic differentiation (relationship) of these strains had no obvious correlation with geographic origin, indicating that there existed frequently interflow among Henan Tobacco Black Shank sub-populations, and no clear sub-group differentiation had been formed.Because the cost of next generation sequencing technique continues to decrease, the analysis of combined genotype reported in this study can be more widely applied to massive and dynamic detection of Tobacco Black Shank and the breeding of tobaccos with resistance to this fungus and rational arrangement of varieties. |
| Key words: Tobacco Black Shank genetic diversity phylogenic evolution nuclear gene mitochondrial gene sequence analysis |
