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Ajilogba, C. F.

Publications and source records attributed to Ajilogba, C. F..

2 recordsLinked to original sources

The biodiversity of eukaryotes in Bambara groundnut rhizosphere

Bambara groundnut has been observed to resist pest and drought, and still able to produce enormous yield when cultivated on poor soil. The advantages of the crop to farmers includes the fact that it produces enormous yield with very low agricultural input. The aim of the present study was to determine the taxonomic and microbial diversity, and identification of eukaryotic organisms in Bambara groundnut rhizosphere using microbiomeanalyst platform. A total of ten soil samples corresponding to the different growth stages were collected from Bambara groundnut rhizosphere over interval period of 4 weeks at North-West University agricultural farm, Mafikeng campus. These samples were assessed for the presence of eukaryotic organisms through polymerase chain reaction (PCR) of 16S ribosomal ribonucleic acid (rRNA) gene. Metagenomics analysis using culture-independent technique (next generation sequencing (NGS)) by Paired end illumina-Miseq technology sequencing with the prospect of discovering novel eukaryotes with plant growth promoting features was used. Statistical analysis was carried out to profile and confirm identities of detected organisms. Fifty-nine (59) features were detected from the 10 samples by microbiomeanalyst under data normalization and data cleaning. Taxonomic analysis showed that, 69% of the eukaryotes in the samples were Peronosporales while Thalassiosiraceae and others were 30% and 1% respectively. There was profound variance difference in the rhizosphere microbiome mainly at the OTU level which largely attributed to those taxa most strongly depleted by the plant. Thalassiosira pseudonana, which is a centric diatom found in marine environment was observed in this study. This is the first time so far that T. pseudonana is observed in plants rhizosphere and its ability to withstand harsh environmental variation might contribute to the ability of Bambara groundnut to be able to withstand drought, pests and diseases.

plant biology↗

BAMBARA GROUNDNUT RHIZOBACTERIA ANTIMICROBIAL AND BIOFERTILIZATION POTENTIAL

Bambara groundnut, an underutilized crop has been proved to be an indigenous crop in Africa with the potential for food security. The rhizosphere of Bambara groundnut like other legumes contains several important bacteria that have not been explored for their plant growth-promoting properties. The aim of this research was to determine the potentials of rhizobacteria from Bambara groundnut soil samples as either biofertilizer or biocontrol agents or both to help provide sustainable agriculture in Africa and globally. Analyses of Bambara groundnut rhizospheric soil samples included chemical analysis such as nitrogen content analysis using extractable inorganic nitrogen method as well as cation exchangeable capacity using ammonium acetate method. Plant growth-promoting properties of isolated rhizobacteria tested include indole acetic acid, hydrogen cyanide, phosphate solubilization, 1-aminocyclopropane-1-carboxylate and ammonia production activities using standard methods. In addition, antifungal assay dual culture method was used to analyze the biocontrol properties of the isolates. Phylogenetic analysis using 16S rRNA was also carried out on the isolates. Isolated rhizobacteria from bambara groundnut rhizosphere were cultured. All the isolates were able to produce ammonia and 1-aminocyclopropane-1-carboxylate while 4.65%, 12.28% and 27.91% produced Hydrogen cyanide, Indole acetic acid and solubilized phosphate respectively, making them important targets as biocontrol and biofertilizer agents. The growth of Fusarium graminearum was suppressed in vitro by 6.98% of the isolates. Plant growth promoting activities of rhizobacteria from bambara groundnut rhizosphere reveals that it has great potentials in food security as biofertilizer and biocontrol agent against fungal and bacterial pathogens.

molecular biology↗