Purpose of Review

The nematode genus Bursaphelenchus is a highly divergent group containing fungal feeders and obligate and facultative plant parasites. The genus is also known as the phoretic (and parasitic) associates of many groups of insects. Further, two major plant pathogens, B. xylophilus and B. cocophilus, are members of this genus, and several other species are suspected to be weak to moderate plant pathogens. Here, the diversity of vector insects and host/habitat/plant species interactions, as well as phylogenetic relationships, are summarized for Bursaphelenchus species. The hypothetical origins of plant pathogenicity for different species of Bursaphelenchus are then discussed in relation to the bionomics of their vector insects.

Recent Findings

Phylogenetic analyses suggest that the genus is separated into four clades, and the basal clade will be further separated into two new genera. Based on a literature survey, the phoretic host association patterns appear different among the other three true Bursaphelenchus clades, i.e., one clade is mostly associated with bark beetles that occupy relatively dry niches (under bark), whereas the other two clades are associated with various groups of insects inhabiting diverse niches in other relatively humid conditions.

Summary

Plant pathogenicity for a few members is hypothetically derived from the nematodes’ tolerance to the static resistance of host plants, i.e., the nematode species vectored by the insects attacking or interfacing with live plant tissue were provided an opportunity and, in a few cases, possessed the means to manifest plant pathogenicity with serious consequences, i.e., B. xylophilus and B. cocophilus.

中文翻译：

---

Bursaphelenchus和相关线虫的多样性和植物致病性及其与载体生物学的关系

审查目的

线虫属Bursaphelenchus是一个高度分化的群体，其中包含真菌饲养者以及专性和兼性的植物寄生虫。该属也被称为许多昆虫的隐喻（和寄生）同伴。此外，两个主要的植物病原体B. xylophilus和B. cocophilus是该属的成员，并且怀疑还有其他几种物种弱至中等的植物病原体。在这里，总结了Bursaphelenchus物种的媒介昆虫的多样性以及宿主/栖息地/植物物种之间的相互作用以及系统发育关系。不同种类的Bursaphelenchus植物致病性的假想起源 然后讨论它们的媒介昆虫的生物学特性。

最近的发现

系统发育分析表明该属分为四个进化枝，而基础进化枝将进一步分为两个新属。根据一项文献调查，在其他三个真实的Bursaphelenchus进化枝之间，phor生寄主的关联模式似乎有所不同，即，一个进化枝主要与占据相对干燥生态位（在树皮下）的树皮甲虫有关，而其他两个进化枝则与各种甲虫相关。在其他相对潮湿的条件下栖息于不同生态位的昆虫群体。

概要

据推测，少数成员的植物致病性源自线虫对宿主植物的静态抗性的耐受性，即，由昆虫攻击或与活体植物组织介导的线虫物种提供了机会，在某些情况下，还具有表示具有严重后果的植物致病性的手段，即B. xylophilus和B. cocophilus。