ISSN:
1432-0789
Keywords:
Streptomycin
;
Cycloheximide
;
Selective inhibition
;
Mineralization-immobilization
;
Non-target effects
;
Biocide degradation
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Geosciences
,
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
Abstract Streptomycin and cycloheximide were added (3 and 2 mg g-1 dry soil, respectively) single and in combination to a forest soil to follow their possible degradation and their effects on soil mineralization-immobilization processes. After 0, 1, 2, 4, 7, and 10 days of incubation at 25°C and 60% water-holding capacity, measurements were taken of microbial biomass C and N, the evolution of CO2, exchangeable NH inf4 sup+ , 0.5M K2SO4-extractable organic C, and total N in both unfumigated and CHCl3-fumigated soil. The results indicated that during the first 2 days of incubation, soil microorganisms were killed by the antibiotics and/or by CHCl3 and used subsequently as a substrate by the survivors. Thereafter, surviving microorganisms probably also started to use biocidal molecules as an energy and nutrient source. The ratios of biomass C to biomass N and of CO2 evolved to net NH inf4 sup+ produced indicated that both biocides had non-target effects for most of the incubation. Thus, streptomycin and cycloheximide are not suitable in determining the relative contribution from fungi and bacteria to mineralization-immobilization processes in soils.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00570637
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