施用有机肥对侵蚀黑土玉米苗期根内生细菌多样性的影响

Effects of manure application on the diversity of corn root endophytic bacterial communities at seedling stage in eroded Mollisols

为了解根内生细菌群落结构在土壤侵蚀条件下的变化,明确有机肥施用对其多样性的影响,本研究采用LNA-PCR和454高通量测序技术相结合的方法对土壤表层剥离30 cm和施用有机肥处理的玉米苗期根内生细菌群落结构进行研究,以表层土没有剥离和单施化肥处理为对照.试验共获得37820条16S r DNA有效序列,主要分布在4个门35个纲214个属和782个OTU,其中,变形菌门、厚壁菌门、放线菌门和拟杆菌门为优势菌门,但不同样品各菌门分布比例存在差异.土壤侵蚀降低了玉米苗期根内生细菌群落多样性,但增施有机肥可以增加根内生细菌群落多样性,这种作用以表层土剥离30 cm处理表现得更为突出.

In order to investigate the change of root endophytic bacterial communities under soil erosion condition,and to evaluate the response of root endophytic bacteria to manure fertilizer,we adopted the LNA-PCR clamping and 454 bar-coded pyrosequencing methods to study the corn root endophytic bacterial communities under 30 cm topsoil erosion and manure fertilization conditions.No topsoil removing（ 0 cm） and only chemical fertilizer treatment were used as control. A total of37820 valid sequences of 16 S r DNA were obtained,mainly distributed in 4 phyla,35 classes,214 genera and 782 OTUs. The dominant phyla were Proteobacteria,Firmicutes,Actinobacteria and Bacteroidetes,but their proportions varied in different samples. The diversity of corn root endophytic bacteria decreased in soil erosion condition. In the topsoil removing soil and no erosion soil,the diversity of corn root endophytic bacterial communities increased by manure application,and the effect was more obvious in the topsoil removing soil.