Mutagenic studies on the insecticide metasystox-R with allium cepa

Metasystox-R is an organophosphate systemic and contact insecticide. It is being indiscriminately used in some parts of India for the control of sap-feeding insects and mites. Metasystox-R has been shown to be mutagenic by Escherichia coli K12 (Mohn 1973, Wild 1975), Chinese hamster V79 cells sister-chromatid exchange test (Chen et al. 1982), and Ames Salmonella test, Schmid's micronucleus test and human lymphocyte sister-chromatid exchange test (Pandita 1983). Besides these tests the insecticide was found to inhibit in vitro DNA polymerization and transfection of Mycobacteriophage 13 DNA (Pandita 1985). There is no report regarding the effect of Metasystox-R on plant genetic system. With this intention studies were made to find the effect of Metasystox-R on seed germination, gametogenic cells, somatic cells and pollen fertility. As the pesticides can be converted in the plant systems (Plewa 1978) it was felt necessary to carry the progeny test in order to monitor sequentially the genetic damage at different stages of plant growth. The study reported herein provides information about the effect of insecticide on seed germination, mitotic index, chromotoxicity, 2C DNA content and pollen fertility.