AUTHOR=Han Pengjie , Liu Tianrui , Zheng Yuan , Song Ruiqi , Nan Tiegui , Yang Xiaolong , Huang Luqi , Yuan Yuan 

TITLE=A Mycorrhizal Bacteria Strain Isolated From Polyporus umbellatus Exhibits Broad-Spectrum Antifungal Activity

JOURNAL=Frontiers in Plant Science

VOLUME=Volume 13 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2022.954160

DOI=10.3389/fpls.2022.954160

ISSN=1664-462X

ABSTRACT=Many bacteria are found from the rhizosphere (or mycorrhizosphere), which has the ability to promote plant growth. Few studies have reported that this bacterium has both the ability to promote plant growth and the potential to fight multiple fungal pathogens. In this study, twenty-one bacterial strains distributed in 6 genera, including 5 Pseudomonas strains, were isolated from mycorrhizal samples of fungi (Polyporus umbellatus) that rely on fungi to complete their life cycles. Further screening experiments and pot experiment showed that the Pseudomonas strain ZL8 not only significant inhibited the growth of phytopathogenic fungi, but also inhibited the wilting and even promoted the growth of S. miltiorrhiza. In addition, this strain ZL8 was found to have the ability to dissolve phosphate, produce IAA and siderophore. Nineteen compounds were identified from the fermentation broth of strain ZL8, of which 2,4-diacetylphloroglucinol (DAPG) had a significant inhibitory effect on Fusarium spp. with a minimum inhibitory concentration of 6.25–25 μg/mL. Molecular docking predicted that DAPG could bind to myosin I at two unique sites, which may be its mechanism of inhibiting fungal growth. The evaluation results show that strain ZL8 can be used to develop a dual-purpose biocontrol agents and biofertilizer. These results also provide new insights into the discovery and utilization of new resources for biocontrol agents and biolfertilizers.