Photorhabdus Luminescens: Virulent Properties and Agricultural Applications

Photorhabdus luminescens is a gram-negative, bioluminescent bacterium from the family Enterobacteriaceae which has been found in countries across the globe. It is part of a symbiotic relationship with, and resides in the gut of the entomopathogenic nematode, Heterorhabditis bacteriophora. Photorhabdus luminescens produces many virulence factors, toxin complexes and antimicrobial compounds which allow it to kill insect hosts while simultaneously protecting itself and its symbiotic partner from other bacteria. Due to its virulent properties and the ability to infect a wide range of insect hosts, the Photorhabdus luminescens-Heterorhabditis bacteriophora relationship is a promising candidate for agricultural use as a mass produced biological control agent. The use of Photorhabdus luminescens has been deemed safe towards humans, animals, non-target insects, plants, as well as the environment. The entomopathogenic nematode is also exempt from registration regulations in most countries. The significance of Photorhabdus luminescens is the potential for an insecticide that allows different species of insect pests to be effectively controlled by a single natural product rather than multiple chemical products. The purpose of this review is to provide readers with an overview of the safety of Photorhabdus luminescens to the community and environment, to inform readers of the virulence factors associated with the bacteria, and to outline the potential the product possesses as a mass produced biological control agent.