Impact of long‐term pesticide applications on some soil biological parameters

Abstract

The soil oxidative and anaerobic processes, as well as, the microbial biomass were followed during three years in a cotton farm (Tatuí) where the recommended pesticides have been used for several years, and in an experimental field (São Paulo) treated first time with the same pesticides. The oxidative process was monitored by the dehydrogenase (DHA)-activity using triphenyltetrazolium chloride (TTC) as substrate. The anaerobic process was followed by the iron-oxide reduction, and the microbial biomass was estimated by the substrate (glucose)-indiced respiration. Increases in DHA-activity and in the microbial biomass occurred only in the farm soil, with concomitant decreases in iron-reduction. In the experimental field soil, the increases in DHA-activity were followed only by decreases in iron-reduction. Soil characteristics were the determining factor for different biological parameters after pesticide inputs. All the pesticides produced at least one clear but transient effect.

Isolation and characterization of an isoproturon mineralizing Sphingomonas sp. strain SH from a French agricultural soil

“…Several studies have reported the adaptation of soil microflora to IPU degradation in response to repeated exposure to this herbicide over a long period on fields under cultivation El-Sebai et al 2005). The IPU degrading ability of soil microflora has been found to be influenced by various soil and environmental factors (Aislabie and Lloydjones 1995;Andrea et al 2000;Bending et al 2003;El-Sebai et al 2007), among which pH is considered to be a key factor affecting biodegradation not only in isolated cultures Hussain et al 2009;Sun et al 2009) but also in soils (Houot et al 2000;El-Sebai et al 2005).…”

Pesticide Knowledge and Safety Practices among Farm Workers in Kuwait: Results of a Survey

“…However, the indiscriminate and extensive use of pesticides represents one of the major environmental and public health problems all over the world [1,2]. If improperly used, pesticides can lead to secondary pest outbreaks [3], destruction of non-target species [4], soil, water, and air contamination [5,6], and residues in primary and derived agricultural products [7] that endanger both the environment and human health. Farm workers’ exposure to pesticides has been associated with adverse health effects like cancer and birth defects resulting in hundreds of fatalities, the majority of which occur in developing countries [8,9].…”

Influence of repeated applications of glyphosate on its persistence and soil bioactivity

“…Most living organisms do not have this enzyme, which is however, ubiquitous in microorganisms (Busse et al, 2001). The amount and diversity of soil microorganisms are extremely important for soil metabolic processes, because they act on the organic matter decomposition contributing for the soil fertility (Bromilow et al, 1996;Andréa et al, 2000).…”