Jimu Luke, Chen ShuaiFei, Wingfield Michael J, Mwenje Eddie, Roux Jolanda
Department of Plant Production and Soil Science, Forest Science Postgraduate Programme, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Private Bag X20, Hatfield, Pretoria, 0028, South Africa.
Department of Microbiology and Plant Pathology, FABI, University of Pretoria, Private Bag X20, Hatfield, Pretoria, 0028, South Africa.
Antonie Van Leeuwenhoek. 2016 Jan;109(1):21-33. doi: 10.1007/s10482-015-0606-0. Epub 2015 Oct 24.
The Eucalyptus stem canker pathogen Teratosphaeria zuluensis was discovered in South Africa in 1988 and it has subsequently been found in several other African countries as well as globally. In this study, the population structure, genetic diversity and evolutionary history of T. z uluensis were analysed using microsatellite markers to gain an enhanced understanding of its movement in Africa. Isolates were collected from several sites in Malawi, Mozambique, Uganda and Zambia. Data obtained were compared with those previously published for a South African population. The data obtained from 334 isolates, amplified across eight microsatellite loci, were used for assignment, differentiation and genetic diversity tests. STRUCTURE analyses, θ st and genetic distances revealed the existence of two clusters, one dominated by isolates from South Africa and the other by isolates from the Zambezi basin including Malawi, Mozambique and Zambia. High levels of admixture were found within and among populations, dominated by the Mulanje population in Malawi. Moderate to low genetic diversity of the populations supports the previously held view that the pathogen was introduced into Africa. The clonal nature of the Ugandan population suggests a very recent introduction, most likely from southern Africa.
桉树茎溃疡病菌祖鲁球腔菌于1988年在南非被发现，随后在其他几个非洲国家以及全球范围内都有发现。在本研究中，利用微卫星标记分析了祖鲁球腔菌的种群结构、遗传多样性和进化历史，以加深对其在非洲传播情况的了解。从马拉维、莫桑比克、乌干达和赞比亚的多个地点采集了分离株。将获得的数据与之前发表的关于南非种群的数据进行了比较。从334个分离株中获得的数据，通过8个微卫星位点进行扩增，用于归属、分化和遗传多样性测试。STRUCTURE分析、θ st和遗传距离揭示了两个聚类的存在，一个以南非的分离株为主，另一个以赞比西河流域（包括马拉维、莫桑比克和赞比亚）的分离株为主。在种群内部和种群之间发现了高水平的混合现象，以马拉维的穆拉杰种群为主。种群中中度到低度的遗传多样性支持了之前的观点，即该病原体是被引入非洲的。乌干达种群的克隆性质表明其引入时间非常近，很可能来自南部非洲。
