Soil genotoxicity induced by successive applications of chlorothalonil under greenhouse conditions

Abstract

Greenhouse production of vegetables has been developed rapidly in China. High temperature and humidity inside the greenhouse make this environment more suitable for fast reproduction of fungal diseases. Fungicides are among the chemicals used extensively in the greenhouse to prevent crops from invasive infections by phytopathogens; however, little is known about the accumulation of fungicides in soil and their effect on soil quality under greenhouse conditions. In the present study, the accumulation of the fungicide chlorothalonil (CT) and its toxic metabolite hydroxy-chlorothalonil (HCT) in soil as well as their related soil genotoxicity under greenhouse conditions was investigated. The results indicated that both CT and HCT accumulated in soil with repeated applications of CT, and the accumulation level was strongly correlated to application dosage and its frequency. In addition, soil genotoxicity, which was measured by Vicia faba, also increased with the accumulation of CT and HCT, and the main contributor to this phenomenon was CT rather than HCT. The data demonstrated that successive applications of fungicides may result in their accumulation in soil and thus a decline in soil quality.

Degradation of chlorothalonil through a hydrolytic dehalogenase secreted from Bacillus subtilis WB800

“…Similar to many other pesticides, TPN is extremely stable in the environment and has a long half-life and significant cumulative toxicity (Getenga et al, 2000;Kumar et al, 2002;Carlo-Rojas et al, 2004). Under greenhouse conditions, the long-term use of TPN leads to soil genotoxicity (Jin et al, 2014). Thus, owing to the extensive use and difficulty in degradation, TPN could be easily detected in water, soil, greenhouse gases, vegetables and fruits, which adversely affects the environment and causes food safety issues (Ngowi et al, 2007;Kazos et al, 2008;Affam et al, 2014;Pog acean et al, 2014).…”

Reduced mobility of fomesafen through enhanced adsorption in biochar‐amended soil

“…Pesticides are still among the most important tools for improving crop yields in many countries. Yet, environmental contamination from excessive pesticide use is raising concerns worldwide about the possible irrecoverable threats to nontarget organisms in soil and groundwater resources . Because the soil environment is the first environment into which pesticides are sprayed, pesticide adsorption–desorption and leaching are most likely the main processes that influence their bioavailability, environmental mobility, and degradation rate .…”

Probiotic strain Stenotrophomonas acidaminiphila BJ1 degrades and reduces chlorothalonil toxicity to soil enzymes, microbial communities and plant roots

“…The micronucleus test was performed following the protocol of Jin et al ( 2014 ). Each treatment contained six slides.…”

“…While some studies have shown the adverse effects of chlorothalonil on soil microbial community composition, abundance, and enzymatic activities (Hussain et al 2009b ; Teng et al 2017 ; Wu et al 2012 ; Yu et al 2006 ). Owing to a reduced volatilization, illumination intensity, and rainfall, the chlorothalonil accumulates to several folds and, thus causes toxicity to soil organisms and plant roots (Jin et al 2014 ). Therefore, it is necessary to develop efficient and eco-friendly approaches to remediate chlorothalonil-contaminated soil, especially under greenhouse conditions.…”

“…Similarly, Kong et al ( 2014 ) demonstrated the colonization of Alcaligenes faecalis JBW4 in endosulfan-contaminated soil using the same approach. Moreover, the micronucleus assay is successfully applied to determine the soil genotoxicity induced by pesticides and other pollutants (Jin et al 2014 ; Zhang et al 2014b ). Thus, using state-of-the-art methods such as PCR-DGGE, micronucleus and soil enzyme assays, we aimed to investigate the ability of probiotic strain BJ1 to colonize and then degrade chlorothalonil in soil under greenhouse conditions.…”