ABSTRACT

Herbicides are increasingly being used widely in agriculture and aquaculture for controlling noxious weeds. Glyphosate, atrazine and paraquat have been the most widely used herbicides during the past decades in the world including Nigeria due to their effectiveness. This study, assesses and compares the impact of these herbicides on the survival of, Macrotermes bellicosus workers. Worker termites were exposed to the recommended concentration of each herbicide being 2.34ml (obtained from 75ml/16litres of water) for glyphosate, 7.5ml (obtained from 3l/200 litres of water) for paraquat and 3.75g/500ml of water for atrazine (obtained from 120g/16litres of water) per 500ml of water. Percentage mortality was recorded after 12 and 24-hour exposure.Atrazine-based herbicide caused 100% mortality in worker termites while paraquat caused high mortality in termites (92%) and glyphosate 24% mortality after 24-hour exposure. Mortality of termite increased with time. This study demonstrated that when compared atrazine was more toxic to worker termites than paraquat and glyphosate. Atrazine and paraquat herbicide were 4x and 3.8x was more toxic to worker termites than glyphosate respectively. This study showed that although glyphosate caused some mortality it is relatively safe to termite compared to atrazine and paraquat. Results from this study demonstrate that the recommended concentration of these herbicides are toxic to termites and could inhibit their performances in the ecosystem. It is therefore important that farmer employ other forms of weed control (mechanical or cultural control biological methods) methods to ensure food securitylimit the termite’s mortality.