Zhu Wen, Yang Li-Na, Wu E-Jiao, Qin Chun-Fang, Shang Li-Ping, Wang Zong-Hua, Zhan Jiasui
Fujian Key Lab of Plant Virology, Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, Fujian, P. R. China.
Key Lab for Biopesticide and Chemical Biology, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou, Fujian, P. R. China.
Sci Rep. 2015 May 13;5:10094. doi: 10.1038/srep10094.
The mating system plays an important role in the spatiotemporal dynamics of pathogen populations through both its direct and indirect impact on the generation and distribution of genetic variation. Here, we used a combination of microsatellite and phenotypic markers to investigate the spatiotemporal distribution of genetic variation in Phytophthora infestans isolates collected from Fujian, China and to determine the role of sexual reproduction in the dynamics. Although the pathogen populations in this region were dominated by self-fertile genotypes, sexual reproduction only occurred occasionally and its contributions to the population genetic structure of P. infestans and epidemics of late blight in the region were limited. Only 49 genotypes were detected among the 534 isolates assayed and the pathogen populations displayed significant heterozygosity excess. Hierarchical analysis revealed that 21.42% of genetic variation was attributed to the difference among sampling years while only 4.45% was attributed to the difference among locations, suggesting temporal factors play a more important role in the population genetic dynamics of P. infestans than spatial factors in this region. We propose that clonal reproduction, combined with founder effects and long distance dispersal of sporangia, is responsible for the observed pattern of spatiotemporal dynamics in P. infestans.
交配系统通过对遗传变异的产生和分布的直接和间接影响，在病原菌种群的时空动态中发挥着重要作用。在此，我们结合微卫星和表型标记，研究了从中国福建采集的致病疫霉分离株遗传变异的时空分布，并确定有性生殖在其动态中的作用。尽管该地区的病原菌种群以自交可育基因型为主，但有性生殖仅偶尔发生，其对致病疫霉种群遗传结构和该地区晚疫病流行的贡献有限。在检测的534个分离株中仅检测到49种基因型，病原菌种群表现出显著的杂合子过剩。层次分析表明，21.42%的遗传变异归因于采样年份之间的差异，而只有4.45%归因于地点之间的差异，这表明在该地区，时间因素在致病疫霉种群遗传动态中比空间因素发挥更重要的作用。我们认为，克隆繁殖，加上奠基者效应和游动孢子的远距离传播，是导致观察到的致病疫霉时空动态模式的原因。
