Mass Production of Bacillus Penetrans for the Biological Control of Root-Knot Nematodes

Root systems of tomato plants containing large numbers of Meloidogyne females parasitized by Bacillus penetrans were obtained by inoculating the plants with second-stage juveniles infested with spores. These roots were air-dried and finely ground to produce a powdery material which was light, easily handled and stored. A bioassay was developed to enable comparison of the potency of different preparations of the parasite. Such preparations have potential as microbial nematicides. One preparation was incorporated into soil at a rate of 100 mg/kg, and within 24 hours 99% of the Meloidogyne juveniles in the soil were infested with B. penetrans spores.