PDF(Pubmed)
Abstract：
Engineering the plant microbiome with beneficial endophytic bacteria can improve the growth, health, and productivity of the holobiont. Here, we administered two beneficial bacterial strains, Kosakonia VR04 sp. and Rhizobium GR12 sp., to micropropagated grapevine cuttings obtained via somatic embryogenesis. While both strains colonized the plant endosphere, only Rhizobium GR12 sp. increased root biomass under nutritional-deficit conditions, as supported by the plant growth promotion traits detected in its genome. Phylogenetic and co-occurrence analyses revealed that the plant native bacterial community, originally dominated by Streptococcaceae and Micrococcaceae, dramatically changed depending on the inoculation treatments, as invading strains differently affected the relative abundance and the interactions of pre-existing taxa. After 30 days of plantlets\' growth, Pantoea became a predominant taxon, and considering untreated plantlets as references, Rhizobium sp. GR12 showed a minor impact on the endophytic bacterial community. On the other hand, Kosakonia sp. VR04 caused a major change in community composition, suggesting an opportunistic colonization pattern. Overall, the results corroborate the importance of preserving the native endophytic community structure and functions during plant microbiome engineering.IMPORTANCEA better comprehension of bacterial colonization processes and outcomes could benefit the use of plant probiotics in the field. In this study, we applied two different beneficial bacteria to grapevine micropropagated plantlets and described how the inoculation of these strains impacts endophytic microbiota assembly. We showed that under nutritional deficit conditions, the response of the receiving endophytic bacterial communities to the invasion of the beneficial strains related to the manifestation of plant growth promotion effects by the inoculated invading strains. Rhizobium sp. GR12 was able to preserve the native microbiome structure despite its effective colonization, highlighting the importance of the plant-endophyte associations for the holobiont performance. Moreover, our approach showed that the use of micropropagated plantlets could be a valuable strategy to study the interplay among the plant, its native microbiota, and the invader on a wider portfolio of species besides model plants, facilitating the application of new knowledge in agriculture.
摘要：
用有益的内生细菌改造植物微生物组可以改善植物生长，健康,和整体生产力。这里,我们施用了两种有益的细菌菌株，KosakoniaVR04sp.和根瘤菌GR12sp。,通过体细胞胚发生获得的微繁殖葡萄插条。虽然这两种菌株都在植物内圈定居，只有根瘤菌GR12sp。在营养缺乏条件下增加根系生物量，在其基因组中检测到的植物生长促进性状支持。系统发育和共生分析表明，植物本地细菌群落，最初以链球菌科和微球菌科为主，根据接种处理的不同发生了戏剧性的变化，由于入侵菌株对相对丰度和预先存在的分类群的相互作用有不同的影响。幼苗生长30天后，泛菌成为主要的分类单元，考虑到未经处理的小植株作为参考，根瘤菌sp.GR12对内生细菌群落的影响较小。另一方面,Kosakoniasp.VR04引起了社区组成的重大变化，暗示了一种机会主义的殖民模式。总的来说,结果证实了在植物微生物组工程过程中保持原生内生植物群落结构和功能的重要性。IMPORTANCEA更好地理解细菌定植过程和结果可能有利于植物益生菌在该领域的使用。在这项研究中,我们将两种不同的有益菌应用于葡萄微繁殖的小植株，并描述了这些菌株的接种如何影响内生菌群的组装。我们发现在营养缺乏的情况下,接受内生细菌群落对有益菌株入侵的反应与接种入侵菌株对植物生长促进作用的表现有关。根瘤菌sp.GR12能够保留天然微生物组结构，尽管它的有效定殖，强调了植物-内生菌协会对整体性能的重要性。此外，我们的方法表明，使用微繁殖植株可能是研究植物之间相互作用的有价值的策略，它的原生微生物群，入侵者除了模型植物之外还有更广泛的物种组合，促进新知识在农业中的应用。
