Substrate-induced respiration method

Historically, measurement of the microbial biomass has been a tedious, time-consuming occupation involving staining and direct counting or use of culture media and enumeration of individual microbial communities. However, in the last 20 years, a suite of methods have been developed for more rapid assessment of the microbial biomass. These include the substrate-induced respiration method (Anderson and Domsch 1978), the chloroform fumigation-incubation method (Jenkinson and... 

Lin, Q. and Brookes, P. C. (1999a). An evaluation of the substrate-induced respiration method. Soil Biol. Biochem. 31, 1969-1983. 

ISO 14240-1 1997 Soil quality - Determination of soil microbial biomass -Part 1 Substrate-induced respiration method. 

Following excess glucose addition to soil, there is a rapid increase in the rate of evolution of C02-C. Over the first 2 hours, the increase in C02-C is proportional to the size of the initial microbial biomass. After this time the relationship weakens as new microbial cells proliferate (Anderson and Domsch 1978). This method, usually termed substrate induced respiration, provides a rapid means of measuring the microbial biomass. Lin and Brookes (1999a) also showed that it was strongly correlated with ATP and biomass C measured by microscopy. The SIR method, in combination with the use of an antibiotic (streptomycin) and a fungicide (cyclohexamide) can also provide... 

Beare, M. H., C. L. Neely, D. C. Coleman, and W. L. Hargrove. 1990. A substrate-induced respiration (SIR) method for measurement of fungal and bacterial biomass on plant residues. Soil Biol. Biochem. 22 585-594. 

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