Plant growth-promoting traits and biocontrol mechanism of three Pseudomonas strains against Geotrichum citri-aurantii
- 1College of Life Science, Huizhou University
Abstract
Background: Plant growth-promoting rhizobacteria (PGPR) play essential roles in improving plant growth performance and enhancing plant disease resistance. Pseudomonas species are widely recognized as promising beneficial microorganisms owing to their excellent plant growth-promoting and biocontrol potential.
Methods: Three bacterial strains, MBJ003, MBJ016 and MB1046, were isolated from potato and tomato rhizosphere soils collected in Guangdong Province, P.R. China. Taxonomic identification was performed based on morphological characteristics, physiological and biochemical profiles, as well as phylogenetic and whole-genome analyses. Genomic features, plant-growth promoting traits and antifungal activities against Geotrichum citri-aurantii were characterized, and the function of the type VI secretion system (T6SS) in strain MB1046 was explored.
Results: Strain MBJ003 was identified as Pseudomonas paraeruginosa , MB1046 as Pseudomonas palmensis , and MBJ016 represents a novel Pseudomonas species. Whole-genome sequencing uncovered abundant and diverse secondary metabolite biosynthetic gene clusters (BGCs) underlying biocontrol capacity. Additionally, strain MB1046 harbours 17 type VI secretion system (T6SS) components. All three strains exhibited multiple plant-beneficial traits including phosphate solubilization, siderophore synthesis and IAA production, while strain MBJ003 additionally showed protease activity. The three strains displayed strong antagonism toward G. citri-aurantii . Their cell-free fermentation supernatants exerted antifungal effects, with MBJ003 showing the strongest inhibition. In vitro inoculation assays confirmed that these strains effectively control citrus postharvest disease caused by G. citri-aurantii . We further provided insights into the T6SS-mediated antagonism of MB1046 against G. citri-aurantii .
Conclusion: This study systematically characterizes the plant-growth-promoting properties and antifungal mechanism of three Pseudomonas strains. These strains are valuable microbial candidates for developing biocontrol agents to manage crop postharvest diseases.
Related
- Mechanisms of Pseudomonas spp. as plant growth promoting rhizobacteria: plant nutrition and biocontrol
- Whole-genome sequencing and biocontrol functional analysis of Pseudomonas chlororaphis XZL-8 for controlling poplar canker pathogen Cytospora chrysosperma
- Integrated genomic and transcriptomic analysis reveals the biocontrol and plant growth-promoting mechanisms of Burkholderia gladioli PNB20-1 against peanut southern blight
- Genomic and functional characterization of quorum sensing and plant growth-promoting traits in Pseudomonas sp. P77
- Editorial: Salt-stress-relieving and growth-promoting microbial diversity and its interaction mechanism with plant rhizosphere
BibTeX
@article{wang2026plant,
title = {{Plant growth-promoting traits and biocontrol mechanism of three Pseudomonas strains against Geotrichum citri-aurantii}},
author = {Chunling Wang and Lutian Mao and Boshi Zhu and Xing Liu and Xinjian Xv and Jiaxin Zhuo},
journal = {Frontiers in Microbiology},
year = {2026},
month = oct,
doi = {10.3389/fmicb.2026.1970166},
url = {https://www.frontiersin.org/articles/10.3389/fmicb.2026.1970166/full},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Plant growth-promoting traits and biocontrol mechanism of three Pseudomonas strains against Geotrichum citri-aurantii
AU - Chunling Wang
AU - Lutian Mao
AU - Boshi Zhu
AU - Xing Liu
AU - Xinjian Xv
AU - Jiaxin Zhuo
PY - 2026
DA - 2026/10/26
JO - Frontiers in Microbiology
DO - 10.3389/fmicb.2026.1970166
UR - https://www.frontiersin.org/articles/10.3389/fmicb.2026.1970166/full
AB - Background: Plant growth-promoting rhizobacteria (PGPR) play essential roles in improving plant growth performance and enhancing plant disease resistance. Pseudomonas species are widely recognized as promising beneficial microorganisms owing to their excellent plant growth-promoting and biocontrol potential. Methods: Three bacterial strains, MBJ003, MBJ016 and MB1046, were isolated from potato and tomato rhizosphere soils collected in Guangdong Province, P.R. China. Taxonomic identification was performed based on morphological characteristics, physiological and biochemical profiles, as well as phylogenetic and whole-genome analyses. Genomic features, plant-growth promoting traits and antifungal activities against Geotrichum citri-aurantii were characterized, and the function of the type VI secretion system (T6SS) in strain MB1046 was explored. Results: Strain MBJ003 was identified as Pseudomonas paraeruginosa , MB1046 as Pseudomonas palmensis , and MBJ016 represents a novel Pseudomonas species. Whole-genome sequencing uncovered abundant and diverse secondary metabolite biosynthetic gene clusters (BGCs) underlying biocontrol capacity. Additionally, strain MB1046 harbours 17 type VI secretion system (T6SS) components. All three strains exhibited multiple plant-beneficial traits including phosphate solubilization, siderophore synthesis and IAA production, while strain MBJ003 additionally showed protease activity. The three strains displayed strong antagonism toward G. citri-aurantii . Their cell-free fermentation supernatants exerted antifungal effects, with MBJ003 showing the strongest inhibition. In vitro inoculation assays confirmed that these strains effectively control citrus postharvest disease caused by G. citri-aurantii . We further provided insights into the T6SS-mediated antagonism of MB1046 against G. citri-aurantii . Conclusion: This study systematically characterizes the plant-growth-promoting properties and antifungal mechanism of three Pseudomonas strains. These strains are valuable microbial candidates for developing biocontrol agents to manage crop postharvest diseases.
SN - 1664-302X
ER -