EVALUATION OF ACUTE TOXICTIY STUDIES ON COPPER-INDUCED OXIDATIVE STRESS IN LATHYRUS SATIVUS L., (VARIETY RATAN) GERMINATING SEEDS: A BIOMARKER BASED RISK ASSESSMENT

Abstract

Copper has been assigned to be a heavy metal which occurs most abundantly in agricultural soils owing to its large-scale use in metal industry as-well-as in agriculture as fungicides. Mitotic index, rate and categories of anatelophase chromosome aberrations, as well as the frequency and types of metaphase disturbances were scored in root tip meristems of Lathyrus sativus L (variety Ratan) after seed exposure to copper, provided as copper acetate at six concentrations (10, 8, 6, 4, 2, and 1 ppm) respectively. Except the 1 and 2 ppm concentration, all the other concentrations of copper acetate brought forth mito-depressive action. The copper genotoxicity is expressed in the increased levels and rates of chromosome aberrations in mitotic ana-telophase stages including chromosome bridges, laggards and complex aberrations are the most numerous, although multipolarity, fragments and micronuclei are present, but with lower frequency in lower treatments. Metaphases with chromosomes expulsed from equatorial plate are numerically preponderant, followed by C-metaphases. At higher doses (6 ppm onwards) copper exhibited micronucleoli formation and nucleolar disintegration i.e., micronucleoli formation in germinating root tip cells which augmented the fact that although a essential micronutrient, but above suboptimal concentration copper stands out as potential cyto-nuclear poison for plant life which is also proved by inhibition of seed germination percentages, root length inhibition, reduction in total soluble protein and disruption of root metabolic activity by inhibition of dehydrogenase activity. These observations constitute a signal about the risks of the widespread and increasing presence of copper in ecosphere and could be considered for a high throughput evaluation of copper and its effects on other organisms, even on human health, due to large use of copper compounds, inclusively as pesticides and fungicides.