Optimizing Entomopathogenic Nematode Genetics and Applications for the Integrated Management of Horticultural Pests

Abstract

Entomopathogenic nematodes (EPNs) can kill and recycle in their host populations, which bodes well for EPNs’ exploitation in long-term and safe pest management. However, EPNs’ cost and efficacy need transformational technology to supplant less expensive and more effective but toxic/unhealthy pesticides. A technology that allows for the significant uptake of commercial EPNs should both boost their market suitability and provide genetic improvements. This review provides brief overviews of EPNs’ biology and ecology from the standpoint of pest/pathogen management as a prerequisite for EPN improvements. Understanding the biology and ecology of EPNs, particularly their symbiotic relationships with bacteria, is crucial to their effective use in pest management. This review provides relevant insights into EPN-symbiotic bacteria and the EPN–symbiont complex. The symbiotic relationship between EPNs and bacteria plays a key role in IPM, providing unique advantages. Either of them can be included in mechanisms underlying the various positive sides of plant–insect interactions in emerging integrated pest management (IPM) systems. Recent approaches, in which EPNs can act additively or synergistically with other production inputs in IPM programs, are discussed for further expansion. The simultaneous favorable effects of EPNs and/or their mutualistic bacteria on several pest/pathogen species of crops should be identified. Merits, such as the rapid killing of insect pests, ease of EPN/the symbiont’s mass production and a broad host range, are presented in order to widely disseminate the conditions under which EPN usage can offer a cost-effective and/or value-added technique for IPM. To maximize the effectiveness of EPNs in IPM, various genetic improvement techniques are being explored. Such techniques, along with their merits/demerits and related tools, are reviewed to optimize the common biocontrol usage of EPNs. Examples of genetic improvements to EPNs that allow for their use in transformational technology, such as a cost-effective application technique, increased infectivity, and toleration of unfavorable settings, are given. Proper production practices and genetic techniques should be applied carefully to avoid undesirable results; it is suggested that these are considered on a case-by-case basis. This will enable us to optimize EPN performance based on the given variables.