Changes in Soil Enzymatic Activity and Control of Meloidogyne incognita using Four Organic Amendments


  • J. A. Chavarria-Carvajal
  • R. Rodriguez-Kabana


Biological Control, Glycine Max, Meloidogyne incognita, Mucuna deeringiana, Organic Amendments, Pine Bark, Pueraria lobata, Soil Enzymes


Four organic amendments (velvetbean, kudzu, pine bark, and urea-N) were evaluated in separate experiments for the management of the root-knot nematode (Meloidogyne incognita). The amendments were applied to nematode-infested soil at rates of 0 to 5%, placed in pots, maintained moist in a greenhouse (25-30C) for 2 weeks, and planted with 'Davis soybean (Glycine max). The experiments were continued for eight more weeks and harvested ten weeks after treatment. Pre-plant soil samples and post-harvest soil and root samples were analyzed, and the number of M. incognita juveniles and nonparasitic nematodes associated with the soil and root tissues were determined. Soil samples were taken at 0, 2, and 10 weeks after amendment application for determination of soil enzyme activities. At the end of the experiments, data on plant growth were recorded, and the incidence of root galling was determined using the number of galls per gram root and a gall index scale. Most organic amendments were effe