title: Salinity altered root distribution and increased diversity of bacterial communities in the rhizosphere soil of Jerusalem artichoke.
abstract: The interaction between roots and bacterial communities in halophytic species is poorly understood. Here, we used Jerusalem artichoke cultivar Nanyu 1 (NY-1) to characterise root distribution patterns and determine diversity and abundance of bacteria in the rhizosphere soil under variable salinity. Root growth was not inhibited within the salinity range 1.2 to 1.9 g salt/kg, but roots were mainly confined to 0-20 cm soil layer vertically and 0-30 cm horizontally from the plant centre. Root concentrations of K(+), Na(+), Mg(2+) and particularly Ca(2+) were relatively high under salinity stress. High salinity stress decreased soil invertase and catalase activity. Using a next-generation, Illumina-based sequencing approach, we determined higher diversity of bacteria in the rhizosphere soil at high than low salinity. More than 15,500 valid reads were obtained, and Proteobacteria, Acidobacteria, Bacteroidetes and Actinobacteria predominated in all samples, accounting for >80% of the reads. On a genus level, 636 genera were common to the low and high salinity treatments at 0-5 cm and 5-10 cm depth. The abundance of Steroidobacter and Sphingomonas was significantly decreased by increasing salinity. Higher Shannon and Chao 1 indices with increasing severity of salt stress indicated that high salt stress increased diversity in the bacterial communities.
authors: Jiangsu Provincial Key Laboratory of Marine Biology, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, P.R. China.
authors: Hui
authors: H
authors: Yang
authors: Jiangsu Provincial Key Laboratory of Marine Biology, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, P.R. China.
authors: Jinxiang
authors: J
authors: Hu
authors: Jiangsu Provincial Key Laboratory of Marine Biology, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, P.R. China.
authors: Xiaohua
authors: X
authors: Long
authors: Jiangsu Provincial Key Laboratory of Marine Biology, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, P.R. China.
authors: Zhaopu
authors: Z
authors: Liu
authors: Soil Science and Plant Nutrition, School of Earth and Environment, The University of Western Australia, 35 Stirling Highway, Crawley WA 6009, Australia.
authors: Zed
authors: Z
authors: Rengel
mesh_terms: D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D002118:Calcium / Q000737:chemistry / Q000378:metabolism; D006368:Helianthus / Q000254:growth & development / Q000382:microbiology*; D006863:Hydrogen-Ion Concentration; D008274:Magnesium / Q000737:chemistry / Q000378:metabolism; D018517:Plant Roots / Q000254:growth & development / Q000378:metabolism / Q000382:microbiology; D012336:RNA, Ribosomal, 16S / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D058441:Rhizosphere; D054712:Salinity; D017422:Sequence Analysis, DNA; D012964:Sodium / Q000737:chemistry / Q000378:metabolism; D012987:Soil / Q000737:chemistry*; D012988:Soil Microbiology; D014867:Water / Q000737:chemistry
chemical_list: D012336:RNA, Ribosomal, 16S; D012987:Soil; D014867:Water; D012964:Sodium; D008274:Magnesium; D002118:Calcium