The Influence of Soil Microorganisms and Bio- or -Organic Fertilizers on Dissipation of Some Pesticides in Soil and Potato Tubers

Abstract

Abstract:The influence of soil microorganisms, biofertilizer and compost fertilization on the persistence of the two organphosphorus insecticides, chlorpyrifos, ethoprophos and carbamate insecticide, carbofuran were studied under semifield experimental conditions.Residue analysis of the initial samples of the three applied pesticides, chlorpyrifos, ethoprophos and carbofuran was relatively high (68.3, 76.0 and 80.9 ppm, respectively) in uncultivated, unfertilized and unsterilized soil. These amounts were decreased to 10.12, 14.6 and 12.0 ppm showing 85.18, 80.79 and 85.17% loss, respectively at 6 weeks after treatments. The initial deposits of these pesticides in potato cultivated soils (control) were 70.77, 74.17 and 81.17 ppm, respectively, graduate dissipation of tested pesticides was noticed through the successive intervals. At the end of the experimental period, residues detected revealed 93.0, 91.5 and 94.37% loss, respectively.Addition of certain bioactive (microbal and compost ) amendments was able to induce the pesticide degradation in the contaminated soil (the highest degradation levels was noticed in biofertilized soil, > 99.99, 99.33 and 96.11%). On the other hands, obtained data clearly showed that microorganisms living in soil play role in pesticide biodegradation. In other words, the percentages of loss of chlorpyrifos, ethoprophos and carbofuran residues were 86.35, 83.91 and 82.32% in sterilized soils, respectively, at 6 weeks after treatments. Obtained data indicated also, the residual values of tested insecticides on or in potato tubers were more than the maximum residue limits (MRL) in all treatments, this means that the tested insecticides have a translocation and accumulating properties in potato tubers.

Isolation and Identification of Pesticides Degrading Bacteria from Farmland Soil

“…Four different locations of Bangladesh were selected for the collection of soil samples and was performed as previous reports suggested the isolation of some pesticide degrading bacteria from pesticide-applied land only [16][17] . This is because the adaptation of the bacteria with the pesticides and also in many cases, pesticides increased the growth rate of the bacteria that can degrade pesticides 18,19 . Using minimal media like Bushnell Haas allows the sole carbon source as pesticides and hence, it is easy to void the bacteria that are not able to degrade pesticides.…”

Role of pesticide application in environmental degradation and its remediation strategies

“…To control soil-borne pests and pathogens soil-applied pesticides accumulated residues and metabolites in the soil at unacceptably high levels. (Shalaby and Abdou, 2010). Depending upon the structure of the pesticide and availability of soil factors, pesticide persistence in the soil fluctuates from a week to several years.…”

Screening of Marine-derived Fungi Isolated from the sponge Didemnun ligulum for Biodegradation of Pentachlorophenol

“…Pesticides used in agriculture remain in the soil at the application site, or are transported to different parts of the environment, such as sediments, plants, surface and ground waters, marine environments and even volatilized into the atmosphere, depending on their physicalchemical properties [14][15][16]. The metabolic fate of the pesticides also depends on the abiotic environmental conditions (temperature, pH, soil moisture), the microbial community, the pesticide characteristics (hydrophilicity, degree of solubility, molecular weight), and the chemical and biological reactions [18].…”