Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO 80309, United States.
Institute of Arctic and Alpine Research, University of Colorado, Boulder, CO 80301, United States.
FEMS Microbiol Ecol. 2023 Apr 7;99(5). doi: 10.1093/femsec/fiad034.
Bacterial and fungal root endophytes can impact the fitness of their host plants, but the relative importance of drivers for root endophyte communities is not well known. Host plant species, the composition and density of the surrounding plants, space, and abiotic drivers could significantly affect bacterial and fungal root endophyte communities. We investigated their influence in endophyte communities of alpine plants across a harsh high mountain landscape using high-throughput sequencing. There was less compositional overlap between fungal than bacterial root endophyte communities, with four 'cosmopolitan' bacterial OTUs found in every root sampled, but no fungal OTUs found across all samples. We found that host plant species, which included nine species from three families, explained the greatest variation in root endophyte composition for both bacterial and fungal communities. We detected similar levels of variation explained by plant neighborhood, space, and abiotic drivers on both communities, but the plant neighborhood explained less variation in fungal endophytes than expected. Overall, these findings suggest a more cosmopolitan distribution of bacterial OTUs compared to fungal OTUs, a structuring role of the plant host species for both communities, and largely similar effects of the plant neighborhood, abiotic drivers, and space on both communities.
细菌和真菌根内共生体可以影响宿主植物的适应性，但根内共生体群落的驱动因素的相对重要性尚不清楚。宿主植物物种、周围植物的组成和密度、空间和非生物驱动因素都可能显著影响细菌和真菌根内共生体群落。我们使用高通量测序技术，在高山恶劣环境下的高山植物中调查了这些因素对根内共生体群落的影响。真菌根内共生体群落的组成重叠程度低于细菌根内共生体群落，在每个采样的根中都发现了四个“世界性”的细菌 OTU，但在所有样本中都没有发现真菌 OTU。我们发现，宿主植物物种（包括来自三个科的九个物种）解释了细菌和真菌群落根内共生体组成的最大变化。我们检测到植物群落、空间和非生物驱动因素对两个群落的解释程度相似，但植物群落对真菌内共生体的解释变化程度低于预期。总的来说，这些发现表明与真菌 OTU 相比，细菌 OTU 的分布更加世界性，植物宿主物种对两个群落都有结构作用，而植物群落、非生物驱动因素和空间对两个群落的影响基本相似。
