Investigation of the Toxic Effects of a Carbamate Insecticide Methiocarb in Allium cepa L.

抄録

The toxic effects of methiocarb insecticide were investigated using bulbs of Allium cepa as test material. Physiological effects were investigated with rooting percentage, root length, and weight gain; Cytogenetic effects were analyzed with micronucleus (MN), chromosomal damage and mitotic index (MI) and anatomical effects were investigated on root tip cell. Biochemical effects were investigated by measuring the malondialdehyde (MDA) levels, catalase (CAT) and superoxide dismutase (SOD) activities. For this aim, A. cepa bulbs were divided into four groups, one control, and three applications; the bulbs in the control group were treated with tap water; the bulbs in the application group were treated with 2.5 mg L⁻¹, 5.0 mg L⁻¹ and 7.5 mg L⁻¹ doses of methiocarb for 72 h. Methiocarb administration caused a decrease in physiological parameters compared to the control group. Methiocarb administration caused an increase in the number of MN and chromosomal damage, and a decrease in MI, besides methiocarb application caused some anatomical damages on cells of root tips. Methiocarb administration caused a dose-dependent increase in CAT and SOD activities and MDA levels compared to the control group. As a result, methiocarb caused toxic effects, and the Allium test material was found to be a useful bioindicator for monitoring these effects.