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Ojuederie, O. B.

Publications and source records attributed to Ojuederie, O. B..

2 recordsLinked to original sources

Spatial and regional directory of tropical Auricularia mushrooms in Southwest, Nigeria

Bioremediation of wastelands and dumpsites in Africa is fast declining due to reduced mushroom populations. In the past, the forest of Africa was teaming with mushrooms, but nowadays; mushrooms are severely exploited, resulting in gradual drift to extinction. Mushrooms have the tendency to degrade recalcitrant wastes and absorb heavy metals (Bio-accumulation). Unless concerted efforts are made to rejuvenate or rescue the surviving mushroom population, Africa will one day be overshadowed by wastes. The mushroom diversity in Southwest, Nigeria was determined by both morphological and molecular markers, 14 primers (OPB-11, OPB-12, OPB-15, OPB-20, OPB-21, OPH-3, OPH-5, OPH-10, OPH-15, OPT-1, OPT-5, OPT-7, OPT-10 and OPT-19) produced polymorphism with the test samples under electrophoresis gel (PCR and RAPD). Using standard morphological markers, Auricularia auricula was found to be evenly distributed across 8 locations in Ekiti and Osun, 6 locations in Ogun, 5 locations in Oyo and 4 locations in Lagos. There was none identified in Ondo. Auricularia polytricha was found in abundance in all the locations in Ondo. Lagos only had 3 out of its outline Stations graced with the presence of A. polytricha, whereas, Ogun, Ekiti, Osun and Oyo had no records of A. polytricha. From the genetic dissimilarity chart, 6 clusters of mushroom, sub-characterized into 3 distinct species (Auricularia polytricha, A. auricula and an unrelated Auricularia outlier species) and 5 cultivars were obtained in the region of Southwest, Nigeria. The population of all the Auricularia mushrooms currently present in Southwest, Nigeria was effectively captioned (Location, type and identity) by this research.

molecular biology↗

Biochemical and Molecular Characterization, and Bioprospecting of Drought Tolerant Actinomycetes from Maize Rhizosphere Soil

Drought is a major limitation to maize cultivation around the globe. Seven actinomycetes strains were isolated from maize rhizosphere soils in Mahikeng, North-West Province, South Africa. The isolates were biochemically characterized and identified with 16S rRNA gene sequence analysis. Isolates were also screened in vitro for abiotic stress tolerance to different concentrations of NaCl, pH, and polyethylene glycol (PEG 8000), as well as for biosynthesis of drought tolerance genes namely Glutathione peroxidase (GPX), Glycine-rich RNA binding protein (GRP), Desiccation protectant protein (DSP), Guanosine triphosphate binding protein (GTP) and plant growth-promoting genes:1-aminocyclopropane-1-carboxylate deaminase (accd) and siderophore biosynthesis (Sid). About 71.43% of isolates were of the genus Streptomyces (99-100% similarity), while 14.29% belong to the genus Arthrobacter (R15) and 14.29% to the genus Microbacterium (S11) respectively (99% similarity). Five isolates had their optimum growth at 35{degrees}C. Arthrobacter arilaitensis (R15) grew and tolerated 5%, 10%, and 20% PEG at 120 h. Root length increased by 110.53% in PEG treated maize seeds (-0.30 MPa) inoculated with Streptomyces pseudovenezuelae (S20) compared to the un-inoculated control. Likewise, germination percentage and vigor index increased by 37.53% and 194.81% respectively in PEG treated seeds inoculated with S20 than the un-inoculated PEG treated seeds. ACC deaminase gene was amplified in all the isolates, while the gene for siderophore biosynthesis was amplified in 85.71% of the isolates. Genes for the synthesis of GPX, GRP, DSP and GTP were amplified in Arthrobacter arilaitensis (R15) and Streptomyces pseudovenezuelae (S20) which lacked GTP. The amplification of drought-tolerant and plant growth-promoting primers indicates the possible presence of these genes in the isolates. These isolates have the potential for use as bio-inoculants, not only to improve drought tolerance in maize but also to be utilized as biofertilizers and biocontrol agents to facilitate growth promotion.

microbiology↗