Wood Decay Characteristics and Interspecific Interactions Control Bacterial Community Succession in Populus grandidentata (Bigtooth Aspen)
Wood Decay Characteristics and Interspecific Interactions Control Bacterial Community Succession in Populus grandidentata (Bigtooth Aspen)
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DOI：
10.3389/fmicb.2019.00979
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发表时间：
2019-05-09
影响因子：
5.2
通讯作者：
Syring, John
中科院分区：
文献类型：
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作者：
Kuramae, Eiko E.;Leite, Marcio F. A.;Syring, John
很少有研究调查细菌群落演替以及细菌分解在木材腐烂过程中的作用。在这里，我们确定了（i）大齿白杨（Populus grandidentata）中细菌的多样性和丰度如何随着腐烂时间顺序而变化； (ii) 细菌群落演替取决于木材的物理和化学特性； (iii)种间细菌相互作用可能介导群落结构。通过 Illumina 对 16S rRNA 扩增子进行测序，从沿着连续腐烂过程采集的样本中鉴定出了 459 个类群，这些样本代表了直立的死树、倒下的木材和土壤。随着分解的进行，群落多样性增加，在分解最严重的树木中达到顶峰。虽然一小部分类群在宿主原木的腐烂状态方面表现出显着的模式，但许多细菌类群遵循随机分布。枯死和倒下的树木和土壤的可用水量和化学成分的变化与细菌群落的变化密切相关。氮是演替的主要驱动力，根瘤菌目的固氮类群在分解早期非常丰富。最近砍伐的原木与死树的微生物群落共享其细菌丰度的 65%，而与土壤的微生物群落仅共享 16%。随着腐烂的进行，细菌群落似乎对资源可用性变化的反应较少，而对种间细菌相互作用的反应更大——我们报告称，在分解的后期阶段，种间相互作用的比例（+9.3%）和强度（+62.3%）都增加了，这表明随着木材腐烂的进行，出现了更复杂的群落结构。
Few studies have investigated bacterial community succession and the role of bacterial decomposition over a continuum of wood decay. Here, we identified how (i) the diversity and abundance of bacteria changed along a chronosequence of decay in Populus grandidentata (bigtooth aspen); (ii) bacterial community succession was dependent on the physical and chemical characteristics of the wood; (iii) interspecific bacterial interactions may mediate community structure. Four hundred and fifty-nine taxa were identified through Illumina sequencing of 16S rRNA amplicons from samples taken along a continuum of decay, representing standing dead trees, downed wood, and soil. Community diversity increased as decomposition progressed, peaking in the most decomposed trees. While a small proportion of taxa displayed a significant pattern in regards to decay status of the host log, many bacterial taxa followed a stochastic distribution. Changes in the water availability and chemical composition of standing dead and downed trees and soil were strongly coupled with shifts in bacterial communities. Nitrogen was a major driver of succession and nitrogen-fixing taxa of the order Rhizobiales were abundant early in decomposition. Recently downed logs shared 65% of their bacterial abundance with the microbiomes of standing dead trees while only sharing 16% with soil. As decay proceeds, bacterial communities appear to respond less to shifting resource availability and more to interspecific bacterial interactions - we report an increase in both the proportion (+9.3%) and the intensity (+62.3%) of interspecific interactions in later stages of decomposition, suggesting the emergence of a more complex community structure as wood decay progresses.