The latest research results of the Innovation Team of Agricultural Microbial Resources of the Institute of Agricultural Resources and Regional Planning (IARRP) of the Chinese Academy of Agricultural Sciences (CAAS), were published online in Nature Communications (IF=16.6) (Nonpathogenic Pseudomonas syringae derivatives and its metabolites trigger the plant "cry for help" response to assemble disease suppressing and growth promoting rhizomicrobiome).

Plants recruit beneficial rhizosphere microbes upon infection by pathogens, forming disease-suppressive soil with functions such as disease control and plant growth promotion. This phenomenon is known as the "cry for help" response, which has been widely verified and recognized in various crops and model plants. However, the canonical "cry for help" response requires the inoculation of pathogenic bacteria, making the theory impractical for agricultural production. Moreover, the mechanism of the "cry for help" response is not clear.

Using a variety of nonpathogenic mutant strains as research materials, the study found that nonpathogenic mutant strains can induce the plant "cry for help" response, recruiting beneficial rhizosphere microbes to form disease-suppressive soil that last for several cropping cycles. The research also identified two strains of Devosia sp. as key microorganisms that dominate disease suppression through the isolation of rhizosphere microorganisms. Furthermore, the study found that the induction of the plant "cry for help" response only requires the typical immune elicitor flagellin peptide (flg22) or the culture supernatant of nonpathogenic strains, while "cry for help" response can be suppressed by the effector-triggered immunity. The results reveal the mechanism by which plants recruit rhizosphere microorganisms through the "cry for help" response and provide a direction for inducing plant disease suppression by developing "plant vaccines" using "detoxified" pathogens.

Researcher Liu Yunpeng from the IARRP and doctoral graduate Zhang Huihui from Nanjing Agricultural University are co-first authors of the paper, while Researcher Zhang Ruifu and Associate Professor Xun Weibing from Nanjing Agricultural University are co-corresponding authors of the paper. The research was supported by the National Key Research and Development Program, the Innovation Program of Chinese Academy of Agricultural Sciences, and the Central Public- interest Scientific Institution Basal Research Fund.

Original article link: https://www.nature.com/articles/s41467-024-46254-3