Effects of Dimethipin on the Osmotic Ground Value and Passive Permeability of Onion Epidermal Cells

Dimethipin이 양파 표피세포의 Osmotic Ground Value 및 Passive Permeability에 미치는 영향

The effects of the defoliant and desiccant dimethipin(2,3-dihydro-5,6-dimethyl-1,4-dithiin-1,1,4,4-tetraoxide) on the passive permeability and osmotic ground value of onion(Allium cepa L.) epidermal cells were investigated by plasmometric method. The osmotic ground value and the water permeability of onion epidermal cells were decreased by 9.8% and 41.2%, respectively, and the passive permeabilities of nonelectrolytesurea, methylurea, ethylurea and malonamide-were also decreased by the range of 15.7%∼57.8% after treatment with 10-3M dimethipin. After treatment with 10-4M dimethipin, the osimotic ground value and the solute permeability of onion epidermal cells were also decreased by 3.7% and 24.5%∼48.8%, respectively, but the water permeability of onion epidermal cells was increased by 8.3%. It was suggested that dimethipin treatment modified the cell membrane of onion epidermis.