Impact of distillery effluent application to land on soil microflora

A pot culture experiment was conducted to evaluate the effect of different treatments of distillery wastewater, i.e. raw, treated, diluted and raw distillery wastewater mixed with domestic waste stabilization pond effluent (1:1) on populations of bacteria, fungi, actinomycetes and nitrogen fixing bacteria. The results indicated that raw wastewater decreased the population of bacteria, fungi and actinomycetes. The growth rates of Rhizobium and Azotobacter were also reduced after raw wastewater application. The toxic effect of raw wastewater was minimized when it was mixed with stabilization pond effluent (1:1), this was demonstrated by an increase in the populations of all the microorganisms studied. When a groundnut plant was irrigated with raw distillery wastewater, no fruits were produced and there was also less nodulation. This study indicates that raw distillery wastewater is very toxic to the soil microorganisms which are important in the soil ecosystem.