Michel Andrew P, Zhang Wei, Kyo Jung Jin, Kang Sung-Taeg, Mian M A Rouf
Department of Entomology, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, OH 44691, USA.
Environ Entomol. 2009 Aug;38(4):1301-11. doi: 10.1603/022.038.0442.
The soybean aphid (Aphis glycines Matsumura) is an invasive pest of cultivated soybean (Glycine max L.) in North America. After the initial invasion in 2000, the aphid has quickly spread across most of the United States and Canada, suggesting large-scale dispersal and rapid adaptation to new environments. Using microsatellite markers from closely related species, we compared the genetic diversity and the amount of genetic differentiation within and among 2 South Korean and 10 North American populations. Overall allelic polymorphism was low, never exceeding four alleles per locus. However, differences in genetic diversity were seen among South Korean and North American populations in terms of heterozygote excesses and genotypic richness. Within North America, two populations (Michigan and Ontario), had lower genetic diversities and exhibited high genetic differentiation compared with the remaining eight populations. The earlier collection time of Michigan and Ontario samples explained the genetic differences better than geographic subdivisions. These data indicate a pattern of small colonizing populations on soybeans, followed by rapid clonal amplification and subsequent large-scale dispersal across North America.
大豆蚜（Aphis glycines Matsumura）是北美栽培大豆（Glycine max L.）的一种入侵性害虫。2000年首次入侵后，这种蚜虫迅速蔓延至美国和加拿大的大部分地区，表明其具有大规模扩散能力并能快速适应新环境。我们使用来自近缘物种的微卫星标记，比较了韩国2个种群和北美10个种群内部及种群间的遗传多样性和遗传分化程度。总体等位基因多态性较低，每个位点从未超过4个等位基因。然而，在杂合子过剩和基因型丰富度方面，韩国和北美种群的遗传多样性存在差异。在北美，与其他8个种群相比，密歇根州和安大略省的两个种群遗传多样性较低，且表现出高度的遗传分化。密歇根州和安大略省样本的较早采集时间比地理细分更能解释这种遗传差异。这些数据表明，大豆上最初是小规模的定殖种群，随后是快速的克隆扩增，以及随后在北美范围内的大规模扩散。
