异质性光照下克隆整合对白夹竹根际土壤细菌共现网络的影响

The Effects of Clonal Integration on the Functional Co-occurrence Network of Rhizosphere Soil Bacterial Communities in Phyllostachys bissetii Subjected to Heterogeneous Light

异质性光照下,克隆植物相连分株间光合产物的传输与共享可能影响分株根际土壤氮素转化过程,但是对调控该过程的细菌网络结构还认识不清.以根状茎克隆植物白夹竹为对象,研究克隆整合对遮荫分株的根际土壤细菌群落组成和共现网络结构特征.相比于根状茎切断处理,根状茎连接导致化能异养、需氧化能异养、硝化作用、好氧氨氧化、好氧亚硝酸盐氧化等与氮素转化过程相关细菌的丰度更高,功能共现网络的平均度和图密度更大,且边和节点数量更多.异质性光照下,克隆整合可能影响分株根际土壤微生物群落功能共现网络的复杂性,进而提升根际土壤氮素转化效率.

Nitrogen turnover in the rhizosphere soil of clonal plants subjected to heterogeneous light may be affected by transmission and sharing of photosynthate among inter-connected ramets.However,our understanding of the bacterial network structure that regulates this process remains unclear.The rhizomatous clonal plant Phyllostachys bissetii was chosen to investigate the effects of clonal integration on the bacterial community composition and its complexity of functional co-occurrence networks in the rhizosphere soil of shaded ramets.α-diversity andβ-diversity of bacterial community in the rhizosphere soil were not significantly affected by the rhizome status.Comparing with severing rhizome,bacteria abundance related to nitrogen turnover processes such as chemoheterotrophy,aerobic chemoheterotrophy,nitrification,aerobic ammonia oxidation and aerobic nitrite oxidation was higher when rhizome retained intact.Average degree and graph density in the functional co-occurrence networks were greater as well as numbers of edge and node.It is suggested that clonal integration may improve nitrogen turnover efficiency in the rhizosphere soil of clonal plant subjected to heterogeneous light with the complexity of the functional microbial co-occurrence network.