Department of Biology, University of Regina, Regina, Saskatchewan, Canada.
FEMS Microbiol Rev. 2011 May;35(3):555-75. doi: 10.1111/j.1574-6976.2011.00264.x. Epub 2011 Feb 15.
Phytopathogens have evolved specialized pathogenicity determinants that enable them to colonize their specific plant hosts and cause disease, but their intimate associations with plants also predispose them to frequent encounters with herbivorous insects, providing these phytopathogens with ample opportunity to colonize and eventually evolve alternative associations with insects. Decades of research have revealed that these associations have resulted in the formation of bacterial-vector relationships, in which the insect mediates dissemination of the plant pathogen. Emerging research, however, has highlighted the ability of plant pathogenic bacteria to use insects as alternative hosts, exploiting them as they would their primary plant host. The identification of specific bacterial genetic determinants that mediate the interaction between bacterium and insect suggests that these interactions are not incidental, but have likely arisen following the repeated association of microorganisms with particular insects over evolutionary time. This review will address the biology and ecology of phytopathogenic bacteria that interact with insects, including the traditional role of insects as vectors, as well as the newly emerging paradigm of insects serving as alternative primary hosts. Also discussed is one case where an insect serves as both host and vector, which may represent a transitionary stage in the evolution of insect-phytopathogen associations.
植物病原体已经进化出专门的致病性决定因素，使它们能够在其特定的植物宿主上定殖并引起疾病，但它们与植物的密切联系也使它们经常与食草昆虫相遇，为这些植物病原体提供了大量的机会来定殖并最终与昆虫进化出替代的联系。数十年的研究揭示了这些联系导致了细菌-载体关系的形成，其中昆虫介导了植物病原体的传播。然而，新兴的研究强调了植物病原菌利用昆虫作为替代宿主的能力，就像它们利用主要植物宿主一样。鉴定介导细菌和昆虫之间相互作用的特定细菌遗传决定因素表明，这些相互作用并非偶然，而是在微生物与特定昆虫在进化过程中反复关联后产生的。这篇综述将讨论与昆虫相互作用的植物病原菌的生物学和生态学，包括昆虫作为载体的传统作用，以及昆虫作为替代主要宿主的新出现的范例。还讨论了一种昆虫既作为宿主又作为载体的情况，这可能代表了昆虫-植物病原体关系进化的一个过渡阶段。
