Improving the efficiency of augmentative biological control with arthropod natural enemies : A modeling approach

A better understanding of the life-history traits of biocontrol agents and their effect on population dynamics is key to obtaining more efficient pest control and generating higher economic returns for biocontrol practitioners. To this end, we constructed an optimality simulation model based on principles of the behavioral ecology of natural enemies. This model allows for the identification of the most important life-history traits of natural enemies (e.g., fecundity, longevity, attack rate, competition and dispersal), taking into account the costs and benefits for biocontrol practitioners. The model was kept general and was designed in such a way that it can be adapted to different target species and their specific ecology (natural enemy-pest-plant combination). Results indicate strong interactions between the optimized life-history traits of the biocontrol agents. Two different optimized life-history strategies for the agents were found with higher potential economic returns. These strategies differ most significantly in the plant-leaving decision and host handling time of the biocontrol agent, but also in their respective fecundity, longevity and dispersal ability. The preferred strategy depends on the number of agents released and the growth rate of the plant. Information from these optimality models can help to determine which agents should be released and how they should be released in a specific agro-ecological situation

Next-generation biological control: the need for integrating genetics and genomics

Biological control is widely successful at controlling pests, but effective biocontrol agents are now more difficult to import from countries of origin due to more restrictive international trade laws (the Nagoya Protocol). Coupled with increasing demand, the efficacy of existing and new biocontrol agents needs to be improved with genetic and genomic approaches. Although they have been underutilised in the past, application of genetic and genomic techniques is becoming more feasible from both technological and economic perspectives. We review current methods and provide a framework for using them. First, it is necessary to identify which biocontrol trait to select and in what direction. Next, the genes or markers linked to these traits need be determined, including how to implement this information into a selective breeding program. Choosing a trait can be assisted by modelling to account for the proper agro‐ecological context, and by knowing which traits have sufficiently high heritability values. We provide guidelines for designing genomic strategies in biocontrol programs, which depend on the organism, budget, and desired objective. Genomic approaches start with genome sequencing and assembly. We provide a guide for deciding the most successful sequencing strategy for biocontrol agents. Gene discovery involves quantitative trait loci analyses, transcriptomic and proteomic studies, and gene editing. Improving biocontrol practices includes marker‐assisted selection, genomic selection and microbiome manipulation of biocontrol agents, and monitoring for genetic variation during rearing and post‐release. We conclude by identifying the most promising applications of genetic and genomic methods to improve biological control efficacy