Here’s How Soil Microorganisms Are Important Bioindicators for Assessing Pesticide Contamination!
Pesticides are an essential part of modern agriculture. Without pesticides, many crops would be vulnerable to pests and diseases, which could drastically reduce yields. However, excessive use of pesticides also creates new problems, especially for non-target organisms such as soil microorganisms.
Soil microorganisms play a major role in maintaining soil fertility and health. When pesticides disrupt them, the functions of the soil ecosystem are weakened. Therefore, monitoring the condition of soil microorganisms can provide important information about the impact of pesticides.
- Sensitivity of Soil Microorganisms to Pesticides
- The Importance of Soil Microorgnisms as Bioindicators
- Testing Methods for Microorganisms as Bioindicators
Sensitivity of Soil Microorganisms to Pesticides
In the soil, microbial communities decompose organic matter, regulate nutrient cycles, and help maintain soil structure. Without them, soil would lose its natural ability to support plant growth.
When pesticides enter the soil, their effects cannot be underestimated. Many sensitive microbes are immediately disturbed, their populations decrease, or they may even disappear altogether. This disrupts the balance of the microbial community.
Ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) are examples of important microorganisms that are vulnerable to pesticides. They play a role in the nitrogen cycle, but their activity can weaken when pesticides accumulate in the soil. This condition disrupts nitrogen availability for plants.
Researchers often use the amoA gene as a molecular marker to detect disturbances in AOA and AOB. From these analyses, it is clear that pesticides can affect very vital groups of microorganisms. The impact can be directly felt in soil quality and crop fertility.
By observing changes in microbial communities, we can gain a more comprehensive picture of pesticide impacts. This is far more informative than merely measuring the remaining amount of pesticide residues.
The Importance of Soil Microorgnisms as Bioindicators
Using soil microorganisms as bioindicators is not only about detecting pesticide residues, but also about understanding the real effects on the biological life of the soil. This allows more accurate monitoring of soil conditions.
Information from bioindicators is highly useful in pesticide management. Farmers can adjust dosages or seek more environmentally friendly alternatives. In this way, crop yields are maintained without compromising soil health.
Ultimately, soil microorganisms can be seen as a natural alarm system. They send signals when the soil is stressed by pesticides. By understanding these warnings, we can sustain agricultural productivity without damaging the environment.
Testing Methods for Microorganisms as Bioindicators
To understand the impact of pesticides on soil microorganisms, researchers use various methods. One of them is the measurement of microbial biomass carbon (MBC) using the fumigation-extraction technique. Low MBC values often indicate microbial stress caused by chemical exposure.
DNA-based methods are also widely used to reveal the structure of microbial communities. For example, 16S rRNA gene sequencing can show which microbes remain present. This makes community shifts caused by pesticides more visible.
In addition, qPCR is a very useful tool. This technique can quantify specific genes, such as amoA in AOA and AOB. With qPCR results, researchers can directly assess how strongly key microbial groups are affected by pesticides.
Soil respiration is another method that provides insight into microbial metabolism. A decline in respiration indicates weakened microbial metabolism due to pesticide stress. This can serve as an early warning of damage to soil ecosystem functions.
To provide further clarity, researchers also calculate the metabolic quotient (qCO₂). A high qCO₂ value indicates that microbes are under stress. By combining these methods, the impact of pesticides can be mapped comprehensively.
Therefore, understanding the impact of pesticides is not sufficient by simply observing plant conditions; it needs to be proven through scientific analysis of soil microorganisms. IML Research provides pesticide testing and soil microorganism monitoring.
Read more:
3 Recommended Pesticide Lab Tests to Pass the Ministry of Agriculture’s Distribution Permit!
IML Research's strength lies in its in-depth DNA-based analysis capabilities, enabling clear detection of changes in microbial community structure, supporting more accurate pesticide management decisions. Discuss your laboratory testing needs with IML Research to maintain land productivity and soil ecosystem health.
Author: Dherika
Editor: Sabilla Reza
References
Bhaduri, D., Sihi, D., Arnab, B., Bibhash, C.V., Sushmita, m., & Biswanath, D. (2022). A Review on Effective Soil Health Bio-Indicators for Ecosystem Restoration and Sustainability. Frontiers in Microbiology, 1-25. Doi: 10.3389/fmicb.2022.938481.
Lamuka, A. P., & Aliwu, P. L. (2024). Analysis of microbial diversity in pesticide-contaminated soil: A study of culturable microorganisms. Environmental and Materials, 2(2), 118–126. https://doi.org/10.61511/eam.v2i2.2024.1435.
Swaine, M., Bergna, A., Oyserman, B., Vasileiadis, S., Karas, P. A., Screpanti, C., & Karpouzas, D. G. (2025). Impact of pesticides on soil health: identification of key soil microbial indicators for ecotoxicological assessment strategies through meta-analysis. FEMS microbiology ecology, 101(6), fiaf052. https://doi.org/10.1093/femsec/fiaf052.
