Influence of glyphosate, other herbicides and genetically modified herbicide-resistant crops on soil microbiota: a review

Abstract

The use of herbicides and genetically modified crops that are herbicide tolerant (HT) is said to adversely affect soil microbial biodiversity, thus negatively influencing the soil ecosystem. Concern has also been raised regarding the potential increase in crop disease incidence and severity caused by the increased cultivation of HT crops and, specifically, the use of glyphosate-resistant (GR) crops. According to reports, the practice could lead to a decrease in soil fertility and plant nutrition, leading to weakened crops that are more susceptible to pathogen attack. Current literature on how glyphosate, other herbicides and HT crops influence soil microbiota is reviewed. Emphasis is placed on negative and positive effects of herbicides per se on soil microbiota. Specific reference is made to the effect of glyphosate and GR crops, either positive or negative, on soil micro-organisms and plant nutrition.

Keywords: genetic modification, glyphosate, herbicides, microbial ecology, resistance

South African Journal of Plant and Soil 2014, 31(4): 177–186