Elimination of inhibitory effects of chlorpyrifos and quinolphos on radish and green gram seed germination by bioremediation of contaminated soil: A comparative study

The effects of Chlorpyrifos and quinolphos on the germination of radish and green gram seeds were tested. Both radish and green gram showed marked reduction in germination percentage and seedling vigour index. The abnormalities and reduction in germination increased with increasing concentration of these pesticides studied. At 50μg of Chlorpyrifos and quinolphos level the germination of radish and green gram seeds were inhibited almost completely on moist filter paper and soil. Protease and amylase activities were reduced in seeds grown on soil spiked with Chlorpyrifos and quinolphos. Bioremediation of Chlorpyrifos and quinolphos-spiked soils with a Chlorpyrifos and quinolphos-degrading microbial consortium helped in eliminating the toxic effects of these pesticides towards seed germination. The degradation of 50μg Chlorpyrifos and quinolphos in soil was complete by 24 hrs. The seed germination and the activities of the assayed enzymes, amylase and protease, were same as before or better in bioremediated soils