Bacterial diversity and total viable counts of bacteria of the different
soil samples from two different localities in Omdurman north region—Karary and Khor Omer sub-regions—were carried out. Soil physical and chemical characteristics (pH, EC, SP,
solublecations: Na, K, Ca, Mg and anion P, organic carbon, total nitrogen and
soil texture) in each studied sub-regions were measured. Qualitative analysis
of microorganisms isolated from the studied soil samples reveals a total of
more than eight different species of bacteria, of which two are unidentified.
The six species are classified under Bacillus genera. In Omdurman north region
soil samples, total bacterial counts ranged from 7.5 × 103 cfu·g﹣1 to 1 × 104 with a mean of 4 × 104 cfu·g﹣1. The quantitative data on microbial population recorded in
the present study were analysed using two diversity indices. High Shannon-Weiner
diversity index value for bacteria was obtained in Khor Omer sub-region
(1.71261). Actinomyces spp.
and Streptomyces spp.
were the most abundant microorganisms identified in the two sub-regions. Total
bacterial count in Karary soil was positively correlated with EC (r = 0.3868), clay
(r = 0.1412), sand (r = 0.5891) and K (r = 0.0265) and negatively correlated
with pH, silt, SP, Na, P, Ca, Mg, N and OC whereas the total bacterial count in
Khor Omer soil was positively correlated with EC (r = 0.3973), clay (r =
0.1966), silt (r = 0.2116), Ca (r = 0.6733), Mg (r = 0.586) and OC (r = 0.2368)
and negatively correlated with pH, sand, SP, Na, K, P and N. There were obvious
differences in correlation coefficients among the selected criteria (37% of the
total number of correlation coefficients were positively correlated between
bacterial counts and soil physico-chemical properties whereas 63% of the total
number were positively correlated between plant type and bacterial counts). The
formulation of an appropriate national strategy in biotechnology should
constitute an important, initial step towards the utilization and industrialization
of microorganisms. The development of molecular techniques of microbial
identification, coupled with traditional methods is promising areas for
continued research.