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This study investigated Bacillus subtilis ATCC13952 as an adsorbent for arsenic in groundwater. Batch experiments were used to determine the effect of contact time, adsorbent dose, arsenic (III) concentration, pH, and temperature on the process. The percentage of arsenic (III) removed was high at a contact time of four days, 3.0 mL of Bacillus subtilis ATCC13952, pH 8 and temperature of 35˚C. The kinetics of the process showed the Elovich kinetics model as the best fit for the process. This indicates that arsenic removal was by chemisorption. The analysis of the nonlinear equilibrium isotherms and the error functions showed the Langmuir isotherm as best fit for the process. Mechanistic study of the process indicated bulk diffusion to be the ratedetermining step. Thermodynamically, the process was favourable, spontaneous and feasible. When the community water samples were treated with the Bacillus subtilis ATCC13952 at the optimum contact time, adsorbent dose, pH and temperature, 99.96% -99.97% of arsenic was removed across all sampling points within the studied communities. Hence, the results show that How to cite this paper:

The demand for resistance cowpea to rust infection has currently increased due to considerable yield losses caused by the fungal pathogen. The study assessed available cowpea genotypes for rust resistance using simple sequence repeat (SSR) markers. Out of 100 cowpea genotypes screened, 97% showed presence of the markers whilst 3% showed absence of the markers. Among the cowpea were 72% resistance, 16% moderate resistance and 9% low resistance to rust. The markers revealed mean high allele frequency (0.86) and low gene diversity (0.24) and polymorphism information content (0.21) among the cowpea genotypes. The markers co-inherited with mean regression value greater than 0.1. There was no clear pattern of clustering among the cowpea genotypes. The cowpea genotypes with rust resistance traits could serve as good sources of germplasm for cultivation or resilient genes with rust target in breeding programmes to improve the crop.