Mass Production of the Beneficial Nematode Heterorhabditis bacteriophora and Its Bacterial Symbiont Photorhabdus luminescens

Abstract

Entomoparasitic nematodes (EPNs) are being commercialized as a biocontrol measure for crop insect pests, as they provide advantages over common chemical insecticides. Mass production of these nematodes in liquid media has become a major challenge for commercialization. Producers are not willing to share the trade secrets of mass production and by doing so, have made culturing EPNs extremely difficult to advance existing technologies. Theoretically, mass production in liquid media is an ideal culturing method as it increases cost efficiency and nematode quantity. This paper will review current culturing methodologies and suggest basic culturing parameters for mass production. This review is focused on Heterorhabditis bacteriophora; however, this information can be useful for other nematode species.

Lab-scale <i>in vitro</i> Mass Production of the Entomopathogenic Nematode <i>Heterorhabditis bacteriophora</i> Using Liquid Culture Fermentation Technology

“…Phase I cells of Photorhabdus luminescence confirmed using NBTA media and bioluminescence were selected and sub-cultured onto nutrient agar until pure colonies of uniform size and morphology were obtained. Phase I absorbs bromothymol blue and produced dark blue colonies by reducing TTC (Triphenyl Tetrazolium chloride), whereas cells of phase II do not absorb bromothymol blue, but reduce TTC and produce red colonies [21,22]. A single colony was transferred to 2x NB broth (in g/l: 5 peptone, 3 beef extract or yeast extract, 5 NaCl) and incubated at 28°C at 150 rpm on orbital shaker (Certomat IS, Sartorius, Germany) for 24 hours.…”

Biological Control Technology Utilizing Heterorhabditis bacteriophora and Steinernema carpocapsae

“…Mass culturing of EPNs through in vitro methods requires in-depth knowledge of nematode biology and the technologies involved in the production (Vashisth et al, 2013). A production medium must be formulated that provides an optimal chemical environment for the nematodes as well as the symbiont bacteria (Inman et al, 2012;Alsaidi et al, 2017). The general in vitro liquid state process is as follows: a nutrient-rich liquid medium is created and mixed with antifoam, autoclaved, inoculated with bacteria and then IJ3 nematodes.…”

Mass Production of the Beneficial Nematode Steinernema carpocapsae Using Solid State Fermentation

“…Time of recovery may be important to achieve an economically feasible production process. Nematode recovery is dependent on various factors including bacterial phase variant, media formulation and bacterial density [21], [22]. Finally, nematode and bacterial density are certainly factors affecting final nematode yield [21], [22].…”