Phytotoxicity Assay of Crude Oil Using Different Accessions of Sorghum bicolor

Abstract: the toxicity of crude oil on ten accessions of sorghum bicolor moench was evaluated in this study. the study used germination, shoot length, root length, chromosomal abnormalities, mitotic indices and ec50 as bioassay parameters in the evaluation with 0% to 8% of crude oil as treatments. the percentage germination of seeds of the different accessions in the different treatments were significantly different (p<0.05; p<0.01 and p<0.001). significant differences also existed in the rates at which the different accessions grew in the different treatment (p<0.05; p<0.01 and p<0.001). chromosomal aberrations ranging from vagrant, bridged anaphase, c-metaphase amongst others were noticed in the cells of the seedlings exposed to the different treatments. the ec50 of the different accession ranged from 5.5% to 19% for germination, 4.4% to 13.8% for root length and 6.3% to 16.7% for shoot length. the mitotic indices of the plants were also affected by the different treatments. the results of the study shows that although the different assay parameters show that crude oil can affect different plants in the different ways, 07/125 is more sensitive to crude oil pollution. further studies can be carried out on the more resistant accessions to determine their suitability for remediation of crude oil contaminated sites .