Lethal toxicity of phosphamidon on the juveniles of Anahas testudineus (Bloch) and Etroplus maculatus (Bloch)

The present study was undertaken to delineate the lethal toxicity of phosphamidon which is a widely used organophosphate pesticide in the paddy fields in Kuttanad the rice bowl of Kerala on Anabas testudineus and Etroplus maculatus. these two species of fishes have important share to contribute to the fishery wealth of Kuttanad. The 48 h LC^^ values of phosphamidon for Anabas and Etroplus were found to be 39.34 and 2.97 ppm respectively. From the experimental results it is apparent that Anabas is much more resistant to phosphamidon than Etroplus. Anabas being an obligate air breathing fish takes in only les pesticide through the gill. These LCj^ values can be utilised for sublethal toxicity studies, which will help to arrive at a maximum allowable toxicant concentration.