Authors : Chioma Bertha Ehis-Eriakha; Charity Willy-Vidona; Stephen Eromosele Akemu
Volume/Issue : Volume 7 - 2022, Issue 4 - April
Google Scholar : https://bit.ly/3IIfn9N
Scribd : https://bit.ly/3POjPbN
DOI : https://doi.org/10.5281/zenodo.6596587
Diazotrophs are nitrogen-fixing micro
organisms responsible for promoting plant growth and
other living organisms. These groups of organisms are
found in soil but most environments have not been
explored to ascertain their presence and activity. This
study, therefore, intends to assess the availability of
diazotrophs in the arable soil within Uzairue community
in Edo State with the objective of evaluating the density,
populations, and identity of diazotrophic bacteria in soil
samples from different cultivable locations using
different microbiological approaches. Soil samples from
the various arable soil were collected using a composite
sampling method specifically from farmlands and
physicochemical parameters were determined such as
nitrate, phosphate, organic matter, organic, and other
properties that can influence microbial activities and
density. The soil samples were enumerated the total
heterotrophic bacterial population and isolation of
nitogen fixation (NF) bacteria was done using N-free
media. The samples had trace levels of phosphate,
nitrogen, and other varying concentrations of
physicochemical parameters. An appreciable population
was observed in the samples which ranged from 4.6 x 106
to 5.1 x 106
. Out of a total of thirty (30) bacterial isolates,
nine (9) showed potential for nitrogen fixation on the Nfree medium and were identified using their
morphological features, biochemical reaction, and
molecular characterization. The result of the research
showed that the identified species have high phenotypic
diversity and were identified to belong to four genera:
Alcaligenes, Pseudomonas, Priestia, and Providencia.
Conclusively the research showed that diazotrophic
bacteria with nitrogenase activity are present in arable
soil which could be harnessed and exploited for green
and sustainable agriculture
Keywords : Diazotrophs, nitrogenase, microorganisms, molecular, agriculture.