IMPACT OF TEXTILE DYEING EFFLUNT ON THE HAEMOPOIETIC TISSUE IN THE LARVAE OF DRAGONFLY DIPLOCODES TRIVIALIS (RAMBUR) LIBELLULIDAE : ANISOPTERA)

The antepenultimate larvae of dragonfly Diplocodes trivialis were collected manually from their breeding places and treated with the textile dyeing effluent which was collected from a local dyeing unit. After the determination of median lethal dose of the effluent to the larvae, three different sub lethal concentrations were selected for long term exposure (30 days) to study the chronic effect of toxicity.In the larvae of Diplocodes trivialis, the haemopoietic tissue is situated in 2nd and 3rd abdominal segment in close association with trachea which could not be isolated. The textile dyeing effluent was found to cause hyperplasia and dysplasia with the degeneration of haemopoietic tissue. The degree of damage depends on the dosage of toxicity.