CIMO/Instituto Politécnico de Bragança, Campus de Santa Apolónia, 5300-253, Bragança, Portugal.
Biosystems & Integrative Sciences Institute (BioISI), Plant Functional Biology Center (CBFP), University of Minho, Campus de Gualtar, 4710-057, Braga, Portugal.
Sci Rep. 2019 Apr 10;9(1):5882. doi: 10.1038/s41598-019-42391-8.
In nature, pathogens live and interact with other microorganisms on plant tissues. Yet, the research area exploring interactions between bacteria-fungi and microbiota-plants, within the context of a pathobiome, is still scarce. In this study, the impact of olive knot (OK) disease caused by the bacteria Pseudomonas savastanoi pv. savastanoi (Psv) on the epiphytic and endophytic fungal communities of olive tree twigs from three different cultivars, was investigated in field conditions. The ITS-DNA sequencing of cultivable fungi, showed that OK disease disturbs the resident fungal communities, which may reflect changes in the habitat caused by Psv. In particular, a reduction on epiphyte abundance and diversity, and changes on their composition were observed. Compared to epiphytes, endophytes were less sensitive to OK, but their abundance, in particular of potential pathogens, was increased in plants with OK disease. Host genotype, at cultivar level, contributed to plant fungal assembly particularly upon disease establishment. Therefore, besides fungi - Psv interactions, the combination of cultivar - Psv also appeared to be critical for the composition of fungal communities in olive knots. Specific fungal OTUs were associated to the presence and absence of disease, and their role in the promotion or suppression of OK disease should be studied in the future.
在自然界中，病原体与植物组织上的其他微生物共生和相互作用。然而，在病生生物组学的背景下，探索细菌-真菌和微生物群-植物之间相互作用的研究领域仍然很少。在本研究中，在田间条件下研究了由细菌丁香假单胞菌 pv. 丁香假单胞菌（Psv）引起的橄榄结（OK）病对来自三个不同品种的橄榄树枝条上的附生真菌和内生真菌群落的影响。可培养真菌的 ITS-DNA 测序表明，OK 病扰乱了定殖真菌群落，这可能反映了 Psv 引起的栖息地变化。特别是，观察到附生生物丰度和多样性减少，以及它们的组成发生变化。与附生真菌相比，内生真菌对 OK 的敏感性较低，但在患有 OK 病的植物中，其丰度，特别是潜在病原体的丰度增加。宿主基因型（在品种水平上）有助于植物真菌的组装，特别是在疾病建立时。因此，除了真菌 - Psv 相互作用外，品种 - Psv 的组合似乎也对橄榄结中真菌群落的组成至关重要。特定的真菌 OTUs 与疾病的存在与否相关，它们在促进或抑制 OK 疾病方面的作用应在未来进行研究。
