Evaluating the Potential of the Entomopathogenic Nematode Heterorhabditis bacteriophora Oswego to Persist in Soils and Soil Mixes Used in the Nursery Production of Woody Ornamentals 1998
Project Leaders: Elson Shields, Tony Testa
Evaluate the potential of the entomopathogenic nematode Heterorhabditis bacteriophora Oswego to persist in soils and soil mixes used in the nursery production of woody ornamentals under both laboratory controlled conditions and greenhouse conditions.
Laboratory study: Data gathered on nematode survival in the laboratory was very similar to previously gathered data on their survival in natural field soils. After 12 weeks the sandy loam soil stored at 23° C became too dry, and the nematodes were killed. Similar conditions occurred at 20 weeks in the sandy loam stored at 15° C. This was due to a labor shortage and too infrequent monitoring of moisture levels. In contrast, the better water holding capacity of the Pro-mix allowed the survival of nematodes during these two critical periods. Nematode survival in the Pro-mix stored at 23° C dropped off dramatically after 12 weeks, but the nematodes in the Pro-mix stored at 15° C in both soils at 5° C were survived well for several months.
Greenhouse study: The ability of the nematodes to remain in the production system is greatly impacted by the watering regime and the soil type used. Top-down watering caused the nematodes to be flushed out of the pots, but with sub-irrigation, the nematodes survived in all soil types for at least 120 days.