基于分子证据探讨松材线虫在中国的传播途径

Possible transmission routes of Bursaphelenchus xylophilus in China based on molecular data

采用11个随机引物对来自中国最早发病的5个省和日本疫区的松材线虫共10个居群进行遗传多样性分析和系统发育分析，拟从分子水平探讨松材线虫病在中国蔓延的可能途径。结果表明：中国松材线虫居群间 存在明显的遗传差异，遗传距离为0．066—0．262；除了安徽明光的居群自成一支外，其他居群均与南京居群聚成一支，其中安徽皖南和浙江岱山居群与南京中山陵居群遗传距离最近，为0．066；安徽明光居群与南京居群的遗传距离最大，为0．262。表明发生在安徽皖南和浙江岱山等地的松材线虫病可能是由最早发病的南京地区扩散的；而发生在毗邻南京的安徽明光的松材线虫病不是由南京地区扩散的。该结果揭示，松木制品的调运等人为远距离传播是松材线虫在我国蔓延的主要途径之一。

In order to reveal possible transmission routes of Bursaphelenchus xylophilus in China, genetic diversity and phylogenetic analysis of 9 B. xylophilus populations from 5 provinces in China and one population in Japan were conducted based on RAPD of 11 random primers. Genetic diversity analysis showed that there was significant genetic variation among different populations of B. xylophilus in China, genetic distances between these populations were from 0. 066 to 0. 262 ; the genetic distance between population of Nanjing and Mingguang, Anhui Province, was the largest （0. 262）, whereas the genetic distance between population of Nanjing and South Anhui and Daishan, Zhejiang Province was the smallest （0. 066）. Phylogenetic analysis revealed that populations of B. xylophilus in China were divided into two clades ： B. xylophilus populations from Nanjing, Zhejiang, Guangdong, Shandong, and South Anhui formed one clade ; another one was made up only by the population of B. xylophilus in Mingguang, which adjacent to Nanjing. It suggested that the origin of pine wood nematode disease in Mingguang was different from that of Nanjing, whereas occurrences of pine wood nematode disease in the other places in China were probably dispersed from Nanjing, where pine wood nematode disease happened firstly in China, which suggested that transmission by imported pine wood packing boards was one of the most important transmission way of B. xylophilus in China.