Pesticide Residues in Soil — Problems Between Concept and Concern

Bacterial Endophytes: Potential Role in Developing Sustainable Systems of Crop Production

“…For example, the long-term and continuous application of crop protection chemicals may adversely affect soil fertility by harming beneficial soil microbial populations (Sturz and Kimpinski, 1999). Readers are referred to review articles on the iatrogenic effects between agrichemicals and nontarget soil microflora, plant pathogens and crops (Bollen, 1993;Ingham 1985;Frehse and Anderson, 1982). Similarly, the relationship between crop amendments and their influence on plant-endophyte interactions, if any, bears detailed examination.…”

The Microbial Degradation of 2,4-Dichlorophenoxyacetic Acid in Soil

“…If 2,4-D degradation is the result of microbial activity, it is logical to try to relate the rate of its disappearance to microbial growth rates and biomass variations in the soils (Soulas 1982). The activity level or physiological state of the 2,4-D-degrading biomass rather than the total microbial biomass in a soil can be expected, by analogy with observations on the herbicide diallate's degradation, to determine the rate of2,4-D degradation, and thus, numbers of2,4-D degraders (Frehse and Anderson 1983).…”

“…In many publications, only the physical and chemical aspects of soils have been described and the biological aspects have been largely ignored (Frehse and Anderson 1983). Workers involved in pesticide degradation studies should become aware ofthe microbiological aspects of the soil in USe.…”

“…Ross et al (1980a) concluded that soil microbial biomass should be measured as soon as possible after sampling, and storage at 4°C was the most suitable for retaining mineral-N values, and adequate over short periods (28 d) for biomass carbon from the CO2 flush and ATP content. Approximately 50% of the initial microbial biomass in the 11 soils from temperate-zone localities had been lost after 10 wk of incubation due to carbon-starvation, and it was suggested that experiments should be terminated after 50% of the biomass has been lost from a soil (Frehse and Anderson 1983). The constant biomass losses seen in un supplemented soils in the laboratory are not common in the field (Frehse and Anderson 1983).…”

Enhanced Biodegradation of Insecticides in Midwestern Corn Soils

“…It has been demonstrated that the level of total microbial biomass in soil can sometimes greatly influence the rate of pesticide degradation (35).…”