Persistence and movement of 1,2 dibromo-3-chloropropane (DBCP), as detected by OLC, indicated rapid degradation in red and sandy loam soils during the first 7 days and thereafter it became slow and almost constant. Degradation in black soil was slow during the first 30 days and then it was rapid. At 60 days, total degradation was 83, 97 and 78 per cent in red, black and sandy loam soils respectively. Movement of DBCP was quicker from upper to lower profile in sandy loam as compared to red and black soils. Mortality of Meloidogyne incognita larvae was directly proportional to the concentrations of DBCP residue in each soil, as tested by bioassay technique, LC60 values in respect to biotoxicity to root knot larvae in red, black and sandy loam soils were 0.39, 0.68 and 0.92 ppm respectively.
DBCP, persistence, residue, soil types, bioefficacy, Meloidogyne incognita
