Designing factories for nematode-based biological control products for an alternative, environmentally friendly management of soil insect pests

Soil insects are a major source of crop loss in tropical, subtropical and temperate zones. Many soil insecticides are either/or highly toxic to humans, have serious other non-target effects, or are a banned from use nationally or internationally. An alternative strategy is the use of beneficial (entomopathogenic) nematodes as they are well-adapted to the soil environment and non-toxic. However, the establishment of locally adapted mass production systems for beneficial nematodes requires considerable technological development effort and time. We therefore analyzed the design of 16 in-vitro semi-solid, 3 in-vivo and 2 combined in-vitro + in-vivo nematode production factories from Rwanda, Switzerland, PR China, DPR Korea, to provide an understanding of the rationale behind factory site selection, as well as external and internal factory designs. The factories should, regardless of the production method, consist of at least six rooms in one building. Their allocation depends on the work-flow, insulation of cultures and storage, as well as on separations to avoid cross-contaminations. Our findings propose optimal standard designs for nematode mass production factories and give insight into steps for planning their establishment. This information will be vital to support the dissemination of such technologies to other locations in-country, or to new countries, with the ultimate aim to more safely control soil pests.   Key words: Biological pest control, entomopathogenic/ entomoparasitic nematodes, technology transfer/exchange, East Africa, East Asia.