Plant growth-promoting microbes, compositions, and uses

A method for assembling a microbial consortium comprising two or more microbial strains associated with plant health, plant growth and/or plant yield, said method comprising the steps of:

• (1) providing a plurality of plant rhizosphere samples;
• (2) isolating a plurality of genomic DNAs from each of the samples provided in step (1);
• (3) determining the sequences of a plurality of 16S rRNA gene segments from each plurality of genomic DNAs isolated in step (2);
• (4) determining the abundance (absolute or relative) of each of said 16S rRNA gene segments in each plurality of 16S rRNA gene segments whose sequences were determined in step (3);
• (5) determining the plant biomass or the abundance of a parameter associated therewith (e.g., plant weight, plant height, root size/length, etc.) or the plant yield for each of the plants from which the rhizosphere samples of step (1) were collected;
• (6) correlating the abundance of each 16S rRNA gene segment determined in step (4) with the plant biomass or the abundance of a parameter associated therewith (e.g., plant weight, plant height, root size/length, etc.) or the plant yield determined in step (5);
• (7) selecting at least one 16S rRNA gene segment whose abundance correlates to the plant biomass or the abundance of a parameter associated therewith (e.g., plant weight, plant height, root size/length, etc.) or the plant yield, as determined in step (6);
• (8) correlating the abundance of the at least one 16S rRNA gene segment selected in step (7) with the abundances of the other of the plurality of 16S rRNA gene segments whose sequences were determined in step (3) across said plurality of samples;
• (9) identifying one or more 16S rRNA gene segments whose abundances correlate with the abundance of the at least one 16S rRNA gene segment selected in step (7) across said plurality of samples;
• (10) identifying two or more microbial strains, which comprises the 16S rRNA gene segments identified in steps (7) and (9), respectively;
• and
• (11) assembling said two or more microbial strains identified in step (10) into a microbial consortium by combining said strains into a single mixture.