Efficacy of Ricinus communis Fruit Meal with and without Bacillus Species on Suppression of Meloidogyne incognita and Growth of Tomato

The efficacy of ground Ricinus communis fruit, with and without Bacillus species, was tested on suppression of Meloidogyne incognita, growth of tomato, soil electrical conductivity (EC) and soil pH. At harvest, 85 days after applying Ricinus organic amendment, Ricinus and initial population nematode density (P_i), accounted for 64–74% of the total treatment variation (TTV) in final population nematode density (P_f) and 53–89% of the TTV in dry shoot weight. Ricinus, P_i and electrical conductivity accounted for 49–69% of the TTV in fresh fruit weight, whereas Ricinus, P_i and Bacillus accounted for 65–82% of the TTV in plant height. Because Bacillus×Ricinus interaction was not significant (P > 0.05) for any variable measured, the efficacy of Ricinus fruit meal was independent of microbial activities.