Pesticides Decrease Bacterial Diversity and Abundance of Irrigated Rice Fields

Abstract

Bacteria play an important role in soil ecosystems and their activities are crucial in nutrient composition and recycling. Pesticides are extensively used in agriculture to control pests and improve yield. However, increased use of pesticides on agricultural lands results in soil contamination, which could have adverse effect on its bacterial communities. Here, we investigated the effect of pesticides commonly used on irrigated rice fields on bacterial abundance and diversity. Irrigated soil samples collected from unexposed, pesticide-exposed, and residual exposure areas were cultured under aerobic and anaerobic conditions. DNA was extracted and analysed by 16S rRNA sequencing. The results showed overall decrease in bacterial abundance and diversity in areas exposed to pesticides. Operational taxonomic units of the genera Enterobacter, Aeromonas, Comamonas, Stenotrophomonas, Bordetella, and Staphylococcus decreased in areas exposed to pesticides. Conversely, Domibacillus, Acinetobacter, Pseudomonas, and Bacillus increased in abundance in pesticide-exposed areas. Simpson and Shannon diversity indices and canonical correspondence analysis demonstrated a decrease in bacterial diversity and composition in areas exposed to pesticides. These results suggest bacteria genera unaffected by pesticides that could be further evaluated to identify species for bioremediation. Moreover, there is a need for alternative ways of improving agricultural productivity and to educate farmers to adopt innovative integrated pest management strategies to reduce deleterious impacts of pesticides on soil ecosystems.

Depicting Fecal Microbiota Characteristic in Yak, Cattle, Yak-Cattle Hybrid and Tibetan Sheep in Different Eco-Regions of Qinghai-Tibetan Plateau

“…Human activities are closely related to pollutants, drugs, chemicals, and antibiotics, which has disturbed the microbiota of the environment and organisms ( 7 ). For instance, the increased Lysinibacillus was highly resistant to heavy metal pollution in farmland systems ( 20 ), and the abundance of Acinetobacter rises in pesticide-exposed areas ( 21 ). Another co-occurring genus, Comamonas , has also been confirmed to be highly correlated with sulfur metabolism, nitrogen metabolism, and the TCA cycle ( 22 ), in accordance with functional predictions.…”

Meta‐omic evaluation of bacterial microbial community structure and activity for the environmental assessment of soils: overcoming protein extraction pitfalls

“…The impact of different pesticides has been assessed by evaluating changes in gene expression and biochemical enzymatic activities and in the diversity and composition of soil bacterial communities (Feld et al ., 2015; Bacmaga et al ., 2018; Storck et al ., 2018; Bacmaga et al ., 2019). A recent study has shown that pesticides decrease the bacterial diversity and abundance in irrigated paddies (Onwona‐Kwakye et al ., 2020). Bioactivity, richness and microbial diversity also decrease when the concentration of heavy metals increase (Yin et al ., 2015; Xie et al ., 2016; Feng et al ., 2018; Liu et al ., 2018; Luo et al ., 2018; Fatimawali et al ., 2020; Thomas IV et al ., 2020; Zhao et al ., 2020).…”

Genotoxic hazard and oxidative stress induced by wastewater irrigated soil with special reference to pesticides and heavy metal pollution

“…Chemical pesticides and heavy metals played a vital role in sustaining crops and livestock yield for several decades and have negative influence on environment ( Duke, 2018 ; Onwona-Kwakye et al., 2020 ). Irrigation of agricultural soils with wastewater have high risk of accumulation of persistent organic and inorganic pollutants in soil.…”