A Review on the Effects of Residual Herbicides on Soil Microorganisms

1Saleh B., 2Jibri S. A., 3Y. B. Kajidu and 4M. S. Gargo

1Department of Agronomy, Faculty of Agriculture, Borno State University, Maiduguri, Nigeria
2Department of Agric Extension, Faculty of Agriculture, Borno State University, Maiduguri, Nigeria
3Department of Crop Production, Faculty of Agriculture, University of Maiduguri, Nigeria
4Department of Agronomy, Kano State University of Science and Technology Wudil, Kano, Nigeria

*Corresponding author: bukarsaleh2017@gmail.com, doi.org/10.55639/607.2333


Herbicides are chemical preparations intended to destroy plants, especially weeds, or to obstruct their growth. After field application, herbicides not only control targeted weeds, but may also have possible lingering effects in the soil, and provide significant exposure of microorganisms to the herbicides. Microorganisms play important role in maintaining soil structure and fertility. Results of different studies show that herbicide application resulted in the reduction of some microbial species, e.g., Proteus spp., and Actinomycetes spp. Bacillus spp. and Pseudomonas spp. these are the microorganisms which were delicate to herbicidal treatment. Significant reductions in fungal activity in both artificial and natural environments as a result of herbicidal treatment were up to 4 times; thus, indicating a positive correlation between growth stoppage and application of the weedicide. Herbicides applied at higher doses are persistent in the soil and harm soil microorganisms. Herbicides such as Paraquat, glyphosate, and atrazine, reduce dehydrogenase activities of the soil. Most herbicides applied to the soil remain in the topmost layer of the soil where the higher concentration of soil microorganisms exist.