Enrichment process of 2,4-D degraders in different soils under upland conditions

Abstract

Abstract The enrichment process of 2,4-D degraders in soil under upland conditions was investigated using samples of a mineral soil and an Ando soil which were stored or not stored. A remarkably higher population of 2,4-D degraders in soils was found when the enumeration was performed using a mineral medium compared with the nutrient broth medium in the MPN method. The population and proliferation rate were proportional to the degradation rate of 2,4-D in the soils examined. 2,4-D was degraded after a longer lag period in the mineral soil after long-term storage than in the fresh soil, but the duration of storage did not affect the degradation rate of 2,4-D after the lag period. Since the population of the 2,4-D degraders decreased through long term soil storage, a longer lag period was required for the proliferation of the degraders to cause an appreciable degradation of 2,4-D in the soil. Storage of the Ando soil did not affect the population size of the degraders and the degradation rate of 2,4-D in th...