Bacterial core community in soybean rhizosphere

콩은 우리나라와 극동아시아가 원산지로 알려져 있으나 국산 콩의 근권 세균 군집에 대한 연구는 미흡하다. 따라서 본 연구에서는 국산 재배콩을 대상으로 차세대 염기서열 분석 방법인 파이로시퀀싱 방법을 사용하여 콩 근권 세균 군집 구조를 해석하고 생육단계별 군집의 변화 및 콩 근권의 핵심 세균 군집을 구명하고자 하였다. 세균 군집 분석 결과, 근권 세균의 군집은 근권과 비근권간에 뚜렷한 차이를 보였으며, 총 21개의 문으로 구성되었다. Proteobacteria가 가장 우점(36.6-42.5%)하였고, Acidobacteria (8.6-9.4%), Bacteroidetes (6.1-10.9%), Actinobacteria (6.4-9.8%), Firmicutes (5.7-6.3%) 등의 순으로 상대풍부도가 감소하였다. 모든 생육단계에 걸쳐 콩 근권의 핵심 세균 군집에는 Proteobacteria에 속한 OTU들이 가장 많이 분포하였으며, 이들 중 Bradyrhizobium에 속한 OTU의 상대 풍부도가 가장 높았다. 본 연구결과는 콩 근권의 핵심 세균 군집은 주로 생육 촉진 기능과 유기물 순환에 관련된 OTU로 구성되어 있다는 것을 보여주었다. Soybean is well known to be originated from Korea and far-east Asian countries, and studies of many root nodule bacteria associated with soybean have mainly-focused on nitrogen fixation, but much less study was carried out on bacterial community in the rhizosphere of soybean. In this study, we analyzed the bacterial community in rhizosphere of Korean soybean, Daepungkong using the pyrosequencing method based on the 16S rRNA gene to characterize the change of the rhizosphere community structure according to the growth stages of soybeans and to elucidate bacterial core community in rhizosphere of soybean. Our results revealed that bacterial community of rhizosphere soil differed from that of bulk soil and was composed of a total of 21 bacterial phyla. The predominant phylum in the rhizosphere of soybean was Proteobacteria (36.6-42.5%) and followed by Acidobacteria (8.6-9.4%), Bacteroidetes (6.1-10.9%), Actinobacteria (6.4-9.8%), and Firmicutes (5.7-6.3%). The bacterial core community in soybean rhizosphere was mainly composed of the operational taxonomic units (OTUs) belonging to the phylum Proteobacteria throughout all growth stages. The OTU00006 belonged to the genus Bradyrhizobium had the highest abundance and Steroidobacter, Streptomyces, Devosia were followed. These results show that bacterial core community in soybean rhizosphere was mainly composed of OTUs associated with plant growth promotion and nutrient cycles.