MICROBIAL DEGRADATION OF 2,2-DICHLOROPROPIONIC ACID IN FIVE SOILS

Abstract

The microbial degradation of 2,2-dichloropropionic acid (dalapon) in five soils was observed under greenhouse and laboratory conditions. Oat plant bioassays revealed that under greenhouse conditions (28 °C) dalapon persisted only 4–8 days in a muck soil, 8–16 days in loam and silty clay loam soils, 16–32 days in sandy loam soil, and 32–64 days in a silty clay soil. An enrichment technique was used to isolate microorganisms effective in the degradation of dalapon from each soil. Although differences in microbial populations among the five soils examined were evident, each soil possessed one or more organisms capable of rapidly degrading dalapon under pure culture conditions. Dalapon degradation by effective microorganisms was affected by organic matter level, pH, cation exchange capacity, and aeration.