Comparing LC50 of Insectisides Pirimicarb and Rotenone on Blowfly, Blowfly larvae, Woodlice and Daphni
Abstract
The LC50 of insecticides rotenone and pirimicarb were compared by testing blowfly, blowfly larva, woodlice and daphnia. Rotenone is a NADH dehydrogenase inhibitor causing death by oxidative stress however pirimicarb causes toxicity through acetylcholinesterase inhibition. It was found that rotenone had large toxic effects on daphnia, blowflies and woodlice but not maggots and pirimicarb had low toxic effects on all of the organisms tested. Due to the low percentage death caused by pirimicarb a LC50, however in rotenone a LC50 was performed for daphnia, woodlice and blowfly the LC50 for each organism was compared concluding that rotenone was most toxic to daphnia.
Introduction
Rotenone is a naturally occurring insecticide derived from the root of Derris Ellipitica and Lonchcarpus species (Nass &Przedborski 2008). It is metabolised in the liver by NADP-linked hepatic microsomal enzymes and is both a contact and systemic insecticide. Rotenone can be used as either a specific or a non-specific broad-spectrum insecticide that has been used since 1848 (Gupra 2012) (Nass & Przedborski 2008). Pirimicarb or Dimethyamino-5,6-dimethylpyrimidin-4-y; N,N-dimethylcarbamate is a synthetic systemic selective insecticide with contact stomach and respiratory action. Pirimicarb was first made by Imperial Chemical Industries and was originally registered in 1974 but withdrawn in 1981(Hutson & Roberts 1999). Woodlice, also known as sowpigs and pillbugs, are isopod crustaceans and are the only known crustaceans to have adapted to life in terrestrial habitats (Punzo 2000). Woodlice have a large surface area and in conjunction with the absence of a lipid layer protecting the cuticle this results in rapid water loss (König & Varma 2006). To prevent