Abstract
Entomopathogenic nematodes in the genera Steinernema and Heterorhabditis, produced through in vitro or in vivo methods, are effective insect biological control agents. In vivo production yields good-quality nematodes, but the costs associated with obtaining insects and labor make this production system have a low economy of scale. Conceivably, if growers can produce their own nematodes, then the cost could be reduced. Grower-based production systems described to-date are not sustainable because they rely on outside sources to obtain or calibrate inoculum. Here, we describe a self-sufficient grower-based system where the grower can produce in-house nematodes after obtaining the initial inoculum from a reliable source. We validated our approach in 2 experiments comparing in vivo nematode production from standard White traps and a grower-based approach using polyacrylamide gel. For both tested species, Steinernema carpocapsae (Weiser) and Heterorhabditis bacteriophora Poinar, the grower-based approach produced equal to or more nematodes than the standard method. For example, when comparing the average yield of S. carpocapsae-infective juveniles per Galleria mellonella cadaver (n = 30), the standard White trap method produced 159,114 ± 9,669, whereas the grower-based approach produced 244,029 ± 16,241. The sustainable system described herein has promise for wide adoption by growers.