Biodegradation and Remediation of Pesticides in Contaminated Agroecosystems: Special Reference to Glyphosate and Paraquat

Abstract

The usage of pesticides in agricultural practices contributes to an improvement in food production through monitoring insects, weeds, and crop diseases, with the aim of ensuring food sustainability to meet the needs of increasing population. However, the widespread application of these substances has numerous harmful consequences on the soil and on both environmental and human health. Moreover, in developed nations, the nonrational usage of chemicals, as well as banned forms, presents a major danger and increases contaminated agricultural lands at alarming rates, as well as polluting surface and groundwater. Glyphosate [N-(phosphonomethyl) glycine] is a broad-spectrum systemic herbicide that blocks the enzyme required by plants to produce amino acids and proteins. At present, in all fields (environment, agriculture, toxicology), it has become important to talk about paraquat (1,1′-dimethyl-4,4′-bipyridium) when it comes to glyphosate. Similarly, in recent years, these two herbicides have been the focus of many toxicities and biodegradation studies. Bioremediation by microbial biotechnology is also one of the most recommended solutions to alleviate the impact of these contaminants and is known to be an environmentally safe soil and water remediation technology. The principle of bioremediation is the modification and removal of pesticides in the form of nontoxic compounds used as nutrients for plants. Several approaches are commonly used, such as biostimulation and bioaugmentation. The discovery of potent microbial strains and the screening of degradation genes are currently a challenge for scientific researchers. In this context, this chapter highlights and summarizes contaminants, their environmental implications, and the biotechnological use of bacteria that may be used for bioremediation in order to remediate polluted areas.