Birt Henry W G, Pattison Anthony B, Skarshewski Adam, Daniells Jeff, Raghavendra Anil, Dennis Paul G
School of Earth and Environmental Sciences, The University of Queensland, Brisbane, QLD, 4072, Australia.
Department of Agriculture and Fisheries, Centre for Wet Tropics Agriculture, 24 Experimental Station Road, South Johnstone, QLD, 4859, Australia.
Environ Microbiome. 2022 Sep 8;17(1):46. doi: 10.1186/s40793-022-00442-0.
Bananas (Musa spp.) are a globally significant crop and are severely afflicted by diseases for which there are no effective chemical controls. Banana microbiomes may provide novel solutions to these constraints but are difficult to manage due to their high diversity and variability between locations. Hence 'common core' taxa, which are a subset of the microbiome that frequent all, or most, individuals of a host species, represent logical targets for the development of microbiome management approaches. Here, we first performed a pot experiment to characterise the effects of two factors that are likely to differ between farms (viz. edaphic conditions and host genotype) on bacterial diversity in bulk soil and seven plant compartments. From this experiment, we created shortlisted core 'candidates' that were then refined using a survey of 52 field-grown Musa spp. We confirmed the importance of the core through network analysis and by comparing the sequences of our core taxa with those reported in 22 previous studies.
Diversity was found to differ between plant compartments and soils, but not genotypes. Therefore, we identified populations that were frequent across most plants irrespective of the soil in which they were grown. This led to the selection of 36 'common core' bacteria, that represented 65-95% of the dominant taxa in field-grown plants and were identified as highly interconnected 'hubs' using network analysis - a characteristic shown to be indicative of microbes that influence host fitness in studies of other plants. Lastly, we demonstrated that the core taxa are closely related to banana-associated bacteria observed on five other continents.
Our study provides a robust list of common core bacterial taxa for Musa spp. Further research may now focus on how changes in the frequencies and activities of these most persistent taxa influence host fitness. Notably, for several of our core taxa, highly similar populations have already been isolated in previous studies and may be amenable to such experimentation. This contribution should help to accelerate the development of effective Musa spp. microbiome management practices.
香蕉（芭蕉属）是一种具有全球重要意义的作物，深受一些尚无有效化学防治方法的病害困扰。香蕉微生物群可能为解决这些限制提供新的方案，但由于其高度的多样性以及不同地点之间的变异性，难以进行管理。因此，“共同核心”分类群作为微生物群的一个子集，经常出现在一个宿主物种的所有或大多数个体中，是微生物群管理方法开发的合理目标。在此，我们首先进行了一项盆栽试验，以表征农场之间可能存在差异的两个因素（即土壤条件和宿主基因型）对大田土壤和七个植物组织中细菌多样性的影响。通过这个实验，我们筛选出了入围的核心“候选者”，然后通过对52株田间种植的芭蕉属植物进行调查对其进行优化。我们通过网络分析以及将我们的核心分类群序列与之前22项研究中报告的序列进行比较，证实了核心的重要性。
发现植物组织和土壤之间的多样性存在差异，但基因型之间没有差异。因此，我们确定了在大多数植物中都很常见的种群，而不论它们生长在何种土壤中。这导致我们选择了36种“共同核心”细菌，它们占田间种植植物中优势分类群的65% - 95%，并且通过网络分析被确定为高度相互连接的“枢纽”——在其他植物的研究中，这一特征表明这些微生物会影响宿主健康。最后，我们证明了这些核心分类群与在其他五大洲观察到的与香蕉相关的细菌密切相关。
我们的研究为芭蕉属植物提供了一份可靠的共同核心细菌分类群清单。现在，进一步的研究可以集中在这些最持久的分类群的频率和活性变化如何影响宿主健康上。值得注意的是，对于我们的几个核心分类群，在之前的研究中已经分离出了高度相似的种群，并且可能适合进行此类实验。这一贡献应有助于加速有效的芭蕉属植物微生物群管理实践的发展。
