Contrasting rhizosphere microbial communities between fertilized and bio-inoculated millet

We used metagenome sequencing by Illumina to identify the core microbiome of the finger millet rhizosphere. Finger millet is an important food security crop and here we report the effect of bioinoculants and synthetic fertilizer on the microbial communities in its rhizosphere. Different taxonomic microbial populations were assessed using the amplification of the 16s rDNA hypervariable V3-V4 regions on the Miseq Illumina platform, with 2 x 300 PE chemistry and 1,00,000 reads per sample and were further elucidated using computational biology tools. Metagenome sequencing revealed the presence of taxonomically rich communities associated with the finger millet. We observed an enrichment of beneficial microbes, particularly those associated with the carbon and nitrogen cycles, when bioinoculants were applied. The addition of synthetic fertilizers led to increased plant height, but caused a reduction in microorganisms that benefit soil health, fertility, and crop productivity while simultaneously increasing disease-causing species. This study paves way for further characterization of microbes with beneficial functional traits to secure the productivity of millets sustainably. In addition, the study provides a base for future identification and elucidation of bioinoculant microbes for obtaining higher plant yields with changing weather and environmental conditions.

Automated summary

The study used Illumina metagenome sequencing to identify the core microbiome of finger millet rhizosphere, revealing the effects of bioinoculants and synthetic fertilizers on microbial communities. Application of bioinoculants enriched beneficial microbes, particularly those involved in carbon and nitrogen cycles, while synthetic fertilizers led to increased plant height but reduced beneficial microorganisms and increased disease-causing species. This research provides a foundation for further characterization of microbes with beneficial traits to ensure millet productivity sustainably.