1
|
Wang Y, Duan S, Xu J, Long Y, Zhang S, Li S, Wu L, Zhang Y. Comparison of the colonization ability of Burkholderia strain B23 in the citrus rhizoplane and rhizosphere and assessment of the underlying mechanisms using full-length 16S rDNA amplicon and metatranscriptomic analyses. Microb Biotechnol 2023. [PMID: 36946260 PMCID: PMC10364312 DOI: 10.1111/1751-7915.14248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Revised: 03/05/2023] [Accepted: 03/07/2023] [Indexed: 03/23/2023] Open
Abstract
The characterization of bacterial strains with efficient root colonization ability and the mechanisms responsible for their efficient colonization is critical for the identification and application of beneficial bacteria. In this study, we found that Burkholderia strain B23 exhibited a strong niche differentiation between the rhizosphere and rhizoplane (a niche with more abundant easy-to-use nutrients but stronger selective pressures compared with the tightly adjacent rhizosphere) when inoculated into the field-grown citrus trees. Full-length 16S rDNA amplicon analysis demonstrated that the relative abundance of B23 in the rhizoplane microbiome at 3, 5, and 9 days post-inoculation (dpi) was always higher than that at 1 dpi, whereas its relative abundance in the rhizosphere microbiome was decreased continuously, as demonstrated by a 3.18-fold decrease at 9 dpi compared to 1 dpi. Time-series comparative expression profiling of B23 between the rhizoplane and rhizosphere was performed at representative time points (1, 3, and 9 dpi) through metatranscriptomic analysis, and the results demonstrated that multiple genes involved in the uptake and utilization of easy-to-use carbohydrates and amino acids and those involved in metabolism, energy production, replication, and translation were upregulated in the rhizoplane compared with the rhizosphere at 1 dpi and 3 dpi. Several genes involved in resistance to plant- and microbial competitor-derived stresses exhibited higher expression activities in the rhizoplane compared with the rhizosphere. Furthermore, gene loci responsible for the biosynthesis of the key antifungal and antibacterial metabolites occidiofungin and ornibactin were induced, and their expression levels remained relatively stable from 3 dpi to 9 dpi in the rhizoplane but not in the rhizosphere. Collectively, our findings provide novel lights into the mechanisms underlying the root colonization of the inoculated bacterial strains and serve as a basis for the identification of strains with efficient colonization ability, thus contributing to the development of beneficial bacteria applications.
Collapse
Affiliation(s)
- Yu Wang
- Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education, Yangzhou University, Yangzhou, 225009, China
| | - Shuo Duan
- Citrus Huanglongbing Joint Laboratory, National Navel Orange Engineering Research Center, Gannan Normal University, Ganzhou, Jiangxi, 341000, China
| | - Jin Xu
- Citrus Research and Education Center, Department of Plant Pathology, IFAS, University of Florida, Lake Alfred, Florida, 33850, USA
| | - Yunfei Long
- Citrus Huanglongbing Joint Laboratory, National Navel Orange Engineering Research Center, Gannan Normal University, Ganzhou, Jiangxi, 341000, China
| | - Siyu Zhang
- Citrus Huanglongbing Joint Laboratory, National Navel Orange Engineering Research Center, Gannan Normal University, Ganzhou, Jiangxi, 341000, China
| | - Shixin Li
- Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education, Yangzhou University, Yangzhou, 225009, China
| | - Lijuan Wu
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, China
| | - Yunzeng Zhang
- Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education, Yangzhou University, Yangzhou, 225009, China
| |
Collapse
|