Effect of some herbicides used in Nigeria on Rhizobium phaseoli, Azotobacter vinelandii and Bacillus subtilis
Adeleye, I.A.; Okorodudu, E.; Lawal, O.
Journal of Environmental Biology 25(2): 151-156
2004
ISSN/ISBN: 0254-8704 PMID: 15529871 Document Number: 580491
The effects of three herbicides, namely Agroxone (paraquat dichloride), Atranex 50SC (atrazine) and 2,4-Damine (2,4-D acid and equivalent, 2,4-D), each at 0.001, 0.01, 0.1, 1 and 10 ml/litre, on A. vinelandii, R. phaseoli and B. subtilis, isolated from a bean garden in Lagos, were studied. A control test tube was set up containing 9 ml distilled water without herbicide. Approximately 0.1 ml of the mixture (herbicide+organism) was plated out at intervals of 0, 24, 48, 72, 96, 120, 144 and 168 h using the spread plate technique. The results revealed that 2,4-Damine was the most toxic of the three herbicides and A. vinelandii was found to be most sensitive to the herbicides. There was a reduction in LC50 of herbicides with increased number of days. The percentage survival decreased with increased concentration of herbicides and days for R. phaseoli and A. vinelandii while an initial reduction in population was followed by increased percentage survival of organisms for B. subtilis.