Review: classical biological control of invasive stink bugs with egg parasitoids – what does success look like?

Abstract

Although the enemy release hypothesis forms the theoretical basis for classical (=importation) biological control of invasive pests, its core assumptions are not always examined. This could contribute to unrealistic expectations for some biological control programs. In this paper we examine the assumptions that: (i) enemy release has contributed to the invasive nature of four exotic pentatomids in North America; and (ii) classical biological control with egg parasitoids has been or will be successful in reducing populations of these pests below economically significant levels. First, we review the history of biological control programs against invasive stink bugs to highlight the variable and controversial levels of success of introducing egg parasitoids against stink bugs. Then, we use simple stage-structured matrix models to demonstrate that it may be easy to overestimate the contribution of egg parasitism alone to a reduction in stink bug population growth. Finally, we discuss what realistic expectations might be for success of biological control against invasive stink bugs using egg parasitoids in the context of integrated pest management programs. REFERENCES1 Keane R and Crawley MJ, Exotic plant invasions and the enemy release hypothesis.

Attraction of Brown Marmorated Stink Bugs, Halyomorpha halys, to Blooming Sunflower Semiochemicals

“…As natural enemies of pentatomids, scelionid egg parasitoids have provided various degrees of stink bug suppression (Jones 1995;Laumann et al 2008), and other parasitoids with high rates of parasitism are still considered for biological control of pentatomids (Corrêa-Ferreira and Moscardi 1996;Rice et al 2014). However, a stage-structured matrix model re-examining the efficacy of egg parasitoids for stink bug control cautions against relying solely on these parasitoids as a stand-alone tactic and recommends instead an integrated approach for stink bug management (Abram et al 2020). Although attractive trap crops, in general, can divert insect herbivores away from valuable cash crops (Akotsen-Mensah et al 2017), trap crops may have limited applicability for the management of pentatomids, which readily shift host plants according to their attractiveness throughout the season (Akotsen-Mensah et al 2017;Hokkanen 1991;Mizell et al 2008).…”

Biological control of invasive stink bugs: review of global state and future prospects

“…When a pest has already established in a new region, classical biological control can be an effective means of reducing the reservoir of populations in the wider landscape, thus reducing immigration to crops. However, classical biological control of stink bugs has limitations that have been addressed here and have been recently analysed by Abram et al (2020). Using stage‐structured matrix models, these authors showed that stink bug mortality at the adult stage would be expected to provide a greater reduction of population growth than mortality at the egg stage and that a multi‐tactic approach targeting different stages would be much more effective in reducing populations below the economic injury level.…”

A Journal of the Plague Year

“…The structure, function, activation, specificity, and mode of action of the insect‐active proteins produced by Bacillus thuringiensis in its vegetative stage are discussed 18 . An analysis of the success of biocontrol of invasive stink bugs with egg parasitoids is made by Abram et al 19 . A thoughtful review on the unintended, potentially harmful consequences and risks of biorational insecticides is provided 20 .…”

“…17 The structure, function, activation, specificity, and mode of action of the insect-active proteins produced by Bacillus thuringiensis in its vegetative stage are discussed. 18 An analysis of the success of biocontrol of invasive stink bugs with egg parasitoids is made by Abram et al 19 A thoughtful review on the unintended, potentially harmful consequences and risks of biorational insecticides is provided. 20 A short review on identification and sex pheromones that can be used for management of gall midges is authored by Xu et al 21 And now for something completely different, Stanhope and Weinstein review the arcane topic of insect damage to musical instruments.…”