[Use of gamma-irradiation of soil for analyzing the state of microbial coeneses]

Increasing doses of gamma-irradiation eliminate some physiological and ecologo-trophical groups from microbial cenoses in soil. Soil fungi are least resistant to the action of gamma-irradiation (do not grow on agarized soil (AS) at a dose of 0.5 Mrad). Actinomycetes are more resistant (do not grow on AS at a dose of 0.75 Mrad). Bacteria are most resistant to irradiation. Asporogenous bacteria do not grow on agarized soil at a dose of 1.25 Mrad. Sporogenous bacteria survive at higher doses (1.75 Mrad). The method of gamma-irradiation permits to accomplish differential analysis of ecological groups of soil microflora and experimental synthesis of microbial associations. The effect of gamma-irradiation on soil enzymes is weak compared with autoclaving. gamma-Irradiated soils may serve as a substrate for model experiments during analysis of microbial associations.