LABORATORY STUDIES ON THE CONTROL OF THE LAND SNAILS OF THE NILE DELTA

Abstract

In recent years, the land snails have been found to show a steadily increasing distribution all over the agriculture and orchard lands of the Nile Delta. They cause severe economic damage to crops and fruit orchards where they attack the leaves and fruits (Gruzdyen eta/., 1983). Virtually, there are a wide number of synthetic compounds that have been found to be effective in their control. However, the best molluscicide should be highly selective showing high ability to eradicate the target snails without harming non-target species in close contact with them. It must have a low toxicity to beneficial organisms and humans. Anyhow, lannate is an effective insecticide, but has been recently used as a molluscicide in the control of land snails. Accordingly, the present study was conducted to evaluate efficacy of lannate in the control of two land snails widely distributed all over the Nile Delta through determination its selective toxicity to the snail as compared to mammals in addition to determination of the impact of the molluscicidal concentration on the snails as well as on non-target laboratory mammalian model, Mus musculus. Determination of the concentration-mortalility curves of lannate against the snails and the mouse were used to evaluate the toxic effects of the molluscicide against the two target snails as well as the adverse effects on the mammalian model. Both the hepatopancreas and ovotistis of the snail as well as the liver and gonad of the mammalian models were the organs used .

for assessment of the potency of the molluscicide in the control of the two snail species.