A genus contains one or more species that are closely related to each other. When an organism is given a scientific name, the first part of the name is the genus. For example, Caulobacter crescentus is the Latin binomial name of a microbe found in the genus called Caulobacter.
Read more about how microbes are classified in our section on microbe diversity and find out more about helpful and unhelpful microbes.
These are the top 15 genera (plural of genus) found in our soil sample so far:

More information about different genera of bacteria found in our soil samples are given in the links below thanks to our University of St Andrews STEP 2023 team of undergraduate students who have been writing and editing Simple Wikipedia articles for relevant to our project.
Ranking | Genus found in our soil samples | Biological function (see reference below) | Helpful or unhelpful? |
1 | Rhizobium | Nitrogen-fixing bacteria that assimilate atmospheric oxygen (inorganic compounds used by plants)* | Helpful |
2 | Bradyrhizobium | Nitrogen-fixing bacteria that assimilate atmospheric oxygen (inorganic compounds used by plants)* | Helpful |
3 | Burkholderia | Plant growth promoting bacteria that occupy the rhizosphere* | Helpful |
4 | Streptomyces | Decomposer bacteria that break down organic materials*, source of antibiotics | Helpful |
5 | Nocardia (Simple Wiki) Nocardia | Some species can be a human pathogen | Unhelpful |
6 | Unclassified Bradyrhizobium | Nitrogen-fixing bacteria that assimilate atmospheric oxygen into fixed nitrogen (inorganic compounds used by plants)* | Helpful |
7 | Micromonospora | Some species can be a source of antibiotics | Helpful |
8 | Pseudonocardia | Has antibiotic properties | Helpful |
9 | Nocardioides | Some produce antibiotics, some degrade a variety of pollutants | Helpful |
10 | Pseudomonas | Decomposer bacteria that break down organic materials, denitrifying bacteria that convert nitrates in soil to nitrous oxide (greenhouse gas) or free atmospheric nitrogen, thus depleting soil fertility and reducing agricultural productivity*. | Helpful and unhelpful |
11 | Variovorax (Simple Wiki) Variovorax | Plant growth promoting bacteria that occupy the rhizosphere* | Helpful |
12 | Mycolicibacter | Some species are human and animal pathogens, but most are not | Helpful and unhelpful |
13 | Mesorhizobium | Nitrogen-fixing bacteria that assimilate atmospheric oxygen (inorganic compounds used by plants)* | Helpful |
14 | Mycolicibacterium | Process decaying organic matter for nutrients, some can be pathogens | Helpful and unhelpful |
15 | Mycobacterium | Some species can be human and animal pathogens | Unhelpful |
*Reference: data from https://www.fera.co.uk/media/wysiwyg/crop_health/Big_Soil_Community_-Community_Level_Report_2018_Extract.pdf