EFFECTS OF CASSAVA MILL EFFLUENT ON THE GROWTH OF PUMPKIN PLANTS

The wastes from cassava processing mills are usually discharged uncontrollably into the environment where they cause serious environmental challenges. This research work was undertaken to investigate the effects of the cassava mill effluent on microbiological quality of soil and also to determine the effects of the polluted soil on the growth of plants. Fresh cassava mill effluent. Unpolluted soil samples were collected and analyzed microbiologically. Germination and growth of pumpkin plants were also investigated using soil samples polluted with different concentrations of the cassava mill effluent. The microbial population of the effluent showed the presence of Staphylococcus aureus, Bacillus spp, Streptococcus spp, Pseudomonas aeruginosa, Aspergillus spp, and Candida spp. The bacterial count was 1.4x104cfu/ml while the fungal count was 1.1x103cfu/ml. The results of the analyses of the unpolluted soil and the effluent polluted soil samples showed that the effluent had noticeable effects on the physicochemical and microbiological properties of the soil. The total microbial count increased from 2.2x105cfu/g to 4.6x105cfu/g for bacteria and 1.6x104cfu/g to 3.3x105cfu/g for fungi. The polluted soil showed higher diversity of micro-organisms. The polluted soil also, at higher concentrations of the effluent inhibited the germination of plants. Irrigation of healthy growing plants with 100% concentration of the effluent resulted to the withering of the plants after few days. This research work revealed the fact that the effluents from cassava processing mills have significant effects on the physicochemical and microbiological properties of the surrounding soils and also affected the growth of plants on these soils negatively. It therefore suggested that this effluent should be treated properly before disposal to the environment.