A Community-Based Screening for Targeting Plant Growth-Promoting Bacteria from the Sugarcane Microbiome

Microorganisms colonizing in and on a plant provide myriad benefits to the health of their host. Harnessing plant-associated microbiota seems to be a promising alternative for the future of sustainable agriculture. In this work, microbiome-based screening to target beneficial bacteria under the phylum Actinobacteria was performed and its plant growth-promoting activities were further tested in vitro and in vivo using maize as a plant model. In addition, the bacterial profile of the inoculated-maize rhizosphere in the pot experiment was studied using 16S rRNA-based amplicon sequencing. The in vivo assessment of maize demonstrated that the selected consortium (GYM-I2) enhanced cumulative height and root and shoot dry weight of inoculated plants as compared to the control. The microbiome analysis revealed that bacterial diversity significantly increased in the maize rhizosphere from week 0 to week 4 after inoculation, and a distinct bacterial profile was observed according to the time. The co-occurrence network showed that many hub taxa were identified as belonging to Actinobacteria and Proteobacteria, implying their important role in the community. Altogether, our results indicated that the microbiome-based screening approach can be further applied to design synthetic microbial communities that could enhance plant growth and development.