Brine Thomas J, Viswanathan Satish B, Murphy Alex M, Pate Adrienne E, Wamonje Francis O, Carr John P
Department of Plant Sciences, University of Cambridge, Cambridge, CB2 3EA, UK.
Pest and Pathogen Ecology, National Institute of Agricultural Botany, East Malling, ME19 6BJ, UK.
Virol J. 2023 Sep 22;20(1):216. doi: 10.1186/s12985-023-02184-y.
Plant viruses of the genus Alphaendornavirus are transmitted solely via seed and pollen and generally cause no apparent disease. It has been conjectured that certain plant endornaviruses may confer advantages on their hosts through improved performance (e.g., seed yield) or resilience to abiotic or biotic insult. We recently characterised nine common bean (Phaseolus vulgaris L.) varieties that harboured either Phaseolus vulgaris endornavirus (PvEV1) alone, or PvEV1 in combination with PvEV2 or PvEV1 in combination with PvEV2 and PvEV3. Here, we investigated the interactions of these endornaviruses with each other, and with three infectious pathogenic viruses: cucumber mosaic virus (CMV), bean common mosaic virus (BCMV), and bean common mosaic necrosis virus (BCMNV).
In lines harbouring PvEV1, PvEV1 and PvEV2, or PvEV1, PvEV2 plus PvEV3, the levels of PvEV1 and PvEV3 RNA were very similar between lines, although there were variations in PvEV2 RNA accumulation. In plants inoculated with infectious viruses, CMV, BCMV and BCMNV levels varied between lines, but this was most likely due to host genotype differences rather than to the presence or absence of endornaviruses. We tested the effects of endornaviruses on seed production and seedborne transmission of infectious pathogenic viruses but found no consistent relationship between the presence of endornaviruses and seed yield or protection from seedborne transmission of infectious pathogenic viruses.
It was concluded that endornaviruses do not interfere with each other's accumulation. There appears to be no direct synergy or competition between infectious pathogenic viruses and endornaviruses, however, the effects of host genotype may obscure interactions between endornaviruses and infectious viruses. There is no consistent effect of endornaviruses on seed yield or susceptibility to seedborne transmission of other viruses.
α-内病毒属的植物病毒仅通过种子和花粉传播，通常不会引起明显病害。据推测，某些植物内病毒可能通过提高宿主性能（如种子产量）或增强对非生物或生物胁迫的抗性，从而赋予宿主优势。我们最近鉴定了九个普通菜豆（Phaseolus vulgaris L.）品种，这些品种单独携带菜豆内病毒（PvEV1），或PvEV1与PvEV2组合，或PvEV1与PvEV2和PvEV3组合。在此，我们研究了这些内病毒之间以及它们与三种传染性致病病毒之间的相互作用：黄瓜花叶病毒（CMV）、菜豆普通花叶病毒（BCMV）和菜豆普通花叶坏死病毒（BCMNV）。
在携带PvEV1、PvEV1和PvEV2或PvEV1、PvEV2加PvEV3的品系中，尽管PvEV2 RNA积累存在差异，但各品系间PvEV1和PvEV3 RNA水平非常相似。在接种传染性病毒的植物中，CMV、BCMV和BCMNV水平因品系而异，但这很可能是由于宿主基因型差异，而非内病毒的存在与否。我们测试了内病毒对传染性致病病毒种子生产和种子传播的影响，但未发现内病毒的存在与种子产量或对传染性致病病毒种子传播的保护之间存在一致关系。
得出的结论是，内病毒不会相互干扰积累。传染性致病病毒与内病毒之间似乎没有直接的协同或竞争关系，然而，宿主基因型的影响可能会掩盖内病毒与传染性病毒之间的相互作用。内病毒对种子产量或对其他病毒种子传播的易感性没有一致影响。
