摘要： 在自然界中，植物体同时感染2种或2种以上病毒的现象非常普遍，并且在这种复合侵染中不同病毒间会引起多种多样的相互作用方式，如协同效应、拮抗效应或共存效应。其中拮抗效应中最为著名的是交叉保护现象，也被称为次级排斥现象，其引发的效应表现为病毒复合侵染植物时先侵染病毒会抑制同属或近源的其他病毒的侵染。这一现象多发生在同属的不同种病毒间或同种病毒的不同突变株系之间。对于这一现象机制的可能解释有蛋白质介导的阻力、植物体本体防御介导的阻力以及植物体中RNA沉默途径介导的作用机制等，此外有研究表明病毒编码的沉默抑制子（VSRs）与病毒间的相互作用有关，可能在病毒复合侵染植物的组织的侵染模式中发挥重要的作用。但是任何一种机制都不能完整的解释这种现象，交叉保护作用的机制仍然是不清楚的。本研究主要概述了已知的关于植物病毒拮抗效应及其可能的分子机制，此外还阐述了当前这一现象在农作物保护中的应用。

关键词: 植物病毒, 共同侵染, 相互作用, 交叉保护, 拮抗效应

Abstract: Natural infection of plants by virus occurs commonly and often by two or more plant viruses. Those co-infected phenomenon can result in various effects, such as synergism, antagonism or coexistence. The relatively well-known antagonism is cross-protection, also referred to as super-infection exclusion. This type of interaction occurs when a previous infection with one virus prevents or interferes with subsequent infection by a homologous secondary virus. Most reports of antagonism are of different viruses of the same genus or of different strains of the same virus. Earlier studies reviewed the possible mechanisms of cross protection among virus of the same strains are presented as follows:protein-mediated resistance, the basal immune mechanisms of host plants, defensive reactions mediated by RNA silencing. In addition, the function of various viral suppressors of RNA silencing (VSRs) has important roles in the interactions between viruses in mixed infections. It has been suggested that viral VSRs have important roles in tissue invasion patterns in mixed virus infections. However, none of them can fully explain this phenomenon and the mechanism of cross-protection remains unclear. This review outlines the current state of knowledge concerning the molecular mechanisms behind antagonism between plant viruses. Moreover, the review briefly outlines the past and present attempts to utilize antagonistic interactions among viruses to protect crop plants against destructive diseases.

Key words: Plant viruses, Co-infection, Interaction, Cross-protection, Antagonism

中图分类号: 

• Q945.8