Persistence of dalapon in grassland soil

Summary The persistence of dalapon^* in a grassland oxisol (red-brown sandy loam, pH 5.9) was studied under incubation and soil-perfusion techniques using antibiotics. The ephemeral nature of dalapon-decomposing bacteria was assessed through MPN procedure. Dalapon persisted upto 10 weeks in incubated soils; biodegradation was a major phenomenon as seen in sterileversus non-sterile soils. But, when the soil was perfused, it decomposed within a week; the bacterial population participated majorly in the breakdown process followed by actinomycetes. Dalapon-decomposing bacteria in the soil remained fairly high even after six months of dalapon application to the sward.