Öz
Penoxsulam is a new sulfonamide herbicide used on rice crops for annual
grasses, broadleaf weeds, and sedges control, either grown through
transplanting or direct dry or direct seeding methods of planting. In this
study, Allium cepa ana-telophase and
comet assay were used to examine the cyto-genotoxic effects of herbicide
penoxsulam on A. cepa roots. A. cepa bulbs were exposed to ½xEC50
(12.5 µg/L), EC50 (25 µg/L) and 2xEC50 (50 µg/L) concentrations of penoxsulam for
24, 48, 72 and 96 h. Distilled water and 10 ppm of methyl methanesulfonate (MMS)
were used as negative and positive control groups, respectively. Penoxsulam
showed a cytotoxic effect by reducing root growth and mitotic index (MI), a
genotoxic effect because it statistically increased chromosome aberrations
(CAs, anaphase bridge, chromosomal laggards, polyploidy, disturbed ana-telophase
and stickiness) and DNA damage as compared to control. Liquid
chromatography-tandem mass spectrometry (LC-MS/MS) was also used for
quantitative analysis of penoxsulam in A.
cepa root meristem cells. Further molecular toxicological evaluations
associated in the cyto-genotoxicity of penoxsulam on plants are needed to
confirm these results