The Effect of Glyphosate Harbicide on Soil Fungi

Abstract

Glyphosate herbicide is one of the herbicides used throughout the world and they are very important to agriculture. Despite the role of glyphosate herbicide in agriculture, they also pose direct or indirect threats to the health of humans and also to the nature and survival of soil microorganisms. This study was carried out to determine the effect of glyphosate herbicide on soil fungi. Enumeration of fungal population in the soil samples before and after treatment was carried out. The fungal count was found to be 2.8x10³ cfu/g before the treatment with glyphosate herbicide and the number continued to decrease up to 0.4x10³ cfu/g on the 15th day of glyphosate herbicide treatment. The fungal population decreased upon treatment with glyphosate herbicide when compared to the control, i.e., the untreated soil sample. Glyphosate herbicide causes a greater reduction in fungal count because the fungal populations decreased gradually and complete disappearance of some species occurred after 6 days of treatment, continuing to decrease up to 15 days after treatment. Soil fungi were isolated from the soil before the application of glyphosate herbicide; they include A. niger, A. flavus, Penicillium spp., Microsporium spp., and Trychophyton spp. Upon application of glyphosate herbicide, not all the fungi isolated before treatment survived the effect of glyphosate herbicide. The most frequently isolated fungi that survived up to 15 days of treatment were Aspergillus species (A. flavus and A. niger), while Microsporium spp., Trychophyton spp., and Penicillium spp. disappeared completely after 9 days of treatment.