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• Population genomics can elucidate historical and contemporary population dynamics of natural enemies, their pests, conspecific competitors, and parasitoids. • Demographic models based on genomic data can enhance understanding of trophic level interactions across species. • In this paper we present a proof of concept using population genomic techniques to complement ecological studies of population dynamics across trophic levels. In this paper, we focus on the application of population genomics, including next-generation sequencing and demographic modeling, to enhance the understanding of historical and contemporary trophic level interactions that are a fundamental basis of biological control. We outline how the integration of ecological approaches with population genomics and demographic modeling can provide additional insights into existing trophic interactions and how natural enemies, their parasitoids, and pest species evolve through these interactions, potentially affecting future levels of biological control. We briefly review and summarize our recent population genomic studies of predatory ladybird beetles and discuss how our results provide guidelines for the use of population genomics techniques and population demographic modeling to enhance our understanding of trophic level interactions. Our intent is to demonstrate as a proof of concept, how these methods can supplement currently used techniques and add a complementary genomic aspect to ecological understandings of trophic level interactions, including estimates of effective population sizes of natural enemies and pest species, examination of correlations between these effective population sizes, and evolutionary changes in natural enemies and pest species which may influence levels of biological control. This in combination with experiments and simulations provide a well-rounded framework for using population genomics to inform multi-tier trophic level interactions. [ABSTRACT FROM AUTHOR]

• Classical weed biological control is hardly practiced in Argentina today. • There is a small community of local experts that work mostly for overseas projects. • The National Strategy on Invasive Alien Species promotes biocontrol initiatives. • A prioritization process is developed to select the best target(s) for biocontrol. • Public awareness and outreach activities could help gain biocontrol public support. Argentina hosted pioneering classical weed biological control projects that were carried out by state institutions between the 1970s and 1990s, at a time when the practice was almost unheard of in Latin America. Despite the early development of these initiatives, the discipline did not prosper and all projects were discontinued. Notwithstanding, Argentina continued to provide biological control agents for the control of weeds in many other parts of the world, ensuring the expertise persisted. Although public concern about invasive plants and chemical-dependent agricultural practices has increased over time, it did not lead to a greater acceptance of classical biological control of weeds, which is still regarded with mistrust or ignored in many public and academic circles alike. Furthermore, there are no systems in place to reach a consensus on declaring weeds as targets for biological control in Argentina. In this paper we discuss different ways in which the community of researchers working in the field in Argentina can help relaunch the biological control of weeds, including the preparation of a prioritized list of target species. A list of this kind would not only reduce costs, but also help in developing trust in the discipline of biological control informing regulators and decision makers in this regard. Prospects are brighter today than a few years ago, but considerable communication and educational work on the benefits of this practice is still required to gain more support before it can effectively be re-implemented. [ABSTRACT FROM AUTHOR]

[Display omitted] • Anystis baccarum attacked and fed on smaller phytoseiid predatory mites, but mortality was reduced when A. baccarum was provided with an alternate food source. • Orius insidiosus, Stratiolaelaps scimitus and Delphastus catalinae were rarely attacked by A. baccarum , presumably due to their similarity in size, or limited habitat overlap. • Anystis baccarum was not susceptible to Beauveria bassiana (GHA strain) when exposed to surface residues of conidia on filter paper. A generalist predatory mite, Anystis baccarum (L.), was developed as a new biocontrol agent in Canada, and became commercially available in 2022. Because successful biological control programs in greenhouse crops rely on the release of several natural enemies simultaneously to deal with multiple pest species, this study assessed the interaction of A. baccarum with other commonly used biocontrol agents in laboratory trials. Note that only adult stages were used, because the agents tested are predominantly sold and released as adults. Anystis baccarum killed and consumed the generalist phytoseiid mites, Neoseiulus cucumeris (Oudemans) and Amblyseius swirskii Athias-Henriot; however, the mortality of the phytoseiid mites was reduced when an alternative food, Ephestia kuehniella Zeller eggs, was available. There was no intra-guild interaction between A. baccarum and the soil-dwelling predatory mite, Stratiolaelaps scimitus (Womersley). No statistically significant mortality was observed when Orius insidiosus (Say), a generalist hemipteran, or Delphastus catalinae (Horn), a coccinelid beetle used to control whiteflies, were confined with A. baccarum without alternative food for 24 h. The susceptibility of A. baccarum to the entomopathogenic fungus Beauveria bassiana (Balsamo) GHA strain was evaluated by exposing the mites to conidia in a filter paper bioassay. Differences in mite mortality were not significant across all treatments, and only one case of successful sporulation fungal growth was observed from cadavers recovered in the experiments; similarly, differences in the number of eggs produced were not significant across all treatments. Although the laboratory trials sometimes showed severe predation pressure from A. baccarum on other biocontrol agents, they are likely to be functionally compatible in the greenhouse owing to differences in habitat preferences and availability of other prey (pests) or another food source. Results of the current study provide insights that will enable the development of rational biocontrol programs that include A. baccarum. [ABSTRACT FROM AUTHOR]

• Trichoderma spp. is a BCA widely studied and used in agriculture. • Armillaria spp. is a globally important pathogen of agricultural/forestry species. • So far, there are 30 studies on the effective control of ARR by Trichoderma. • Trichoderma effectively control Armillaria in different experimental conditions. • So far, there are four mechanisms of action identified in this biological control. • More research is needed on the use of Trichoderma against Armillaria. Trichoderma is a genus of filamentous fungi with several species widely studied and used as biological control agents (BCAs) in agriculture. With respect to fungal disease control, Trichoderma spp. can use different mechanisms of action, including mycoparasitism, antibiosis, competition and/or activation of plant defences. Armillaria spp. are the causal pathogens of Armillaria root rot (ARR) disease, which is widely distributed and of great economic and environmental importance in agriculture and forestry. ARR can be devastating to plant health, through colonisation and rotting of the root system and collar of the infected plant/tree, which can cause a reduction in yield and eventually death. Armillaria can live as a saprophyte that survives on dead plant material, making eradication of ARR extremely difficult. In an exhaustive analysis of work published to date on the control of Armillaria spp. by Trichoderma spp., using the WoS and Scopus databases, we identified 31 papers. We discuss these reports in light of their key findings, including number of publications per year, the countries where they were published, the journals and the citations obtained so far. Although the vast majority do not identify the mechanism of action involved in control, some describe mycoparasitism, antibiosis, competition or modification of the rhizospheric microbiota as being responsible for effective biological control of the pathogen. Further research into these mechanisms and additional in-depth analysis of less studied or currently unidentified mechanisms, such as the activation of plant defences, would be highly beneficial to our understanding of Trichoderma as a BCA of Armillaria. [ABSTRACT FROM AUTHOR]

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/policies/article-withdrawal). This article has been retracted at the request of the authors. The strains T. atroviride T11 and T. asperellum T25 are property of the University of Salamanca. Post publication, the authors informed the editor that the material transfer agreement (MTA) between the project sponsor (iQBiotech LLC.) and the owner (University of Salamanca) of the Trichoderma strains tested in this study had been terminated. The authors did not have permission to publish work done with these strains and have therefore requested the retraction of this paper. The authors wish to the apologize to the University of Salamanca and to the readers. [ABSTRACT FROM AUTHOR]

• This paper proposes and describes an interesting and potentially powerful means to validate large-scale biocontrol agent impacts during a Classical biological control (CBC) programme. • The methodology derives the beneficiaries' farmers from the dispersal of parasitoids at a landscape level. • The methodology was applied to the endoparasitoid Fopius arisanus release to control fruit fly Bactrocera dorsalis in Africa. • The study's outcome is appropriate for agriculture stakeholders and development partners to evaluate the benefits of CBC programme. Following the invasion of Africa by the oriental fruit fly, Bactrocera dorsalis , Classical biological control (CBC) has been exploited as a safer alternative for its suppression by the introduction and release of the koinobiont endoparasitoid, Fopius arisanus. Although the parasitoids have been released in several African countries, the extent of their dispersal and the resulting extent in benefits to fruit growers have not yet been elucidated. This paper proposes an innovative, multi-level CBC impact analysis that combines cellular automata (CA) and ecological niche models to estimate parasitoid dispersal ranges and the range of farmers who benefit from it. Firstly, we provided a generic, systematic methodological approach using CA rules incorporated into species distribution. Secondly, the model was used to estimate the dispersal range of the parasitoid, based on the life history and bioecology of the host insect (fruit fly) and the parasitoid. Finally, the parasitoid dispersal coverage was mapped across fruit crops attacked by the target fruit fly, and the number of households that benefited from the parasitoids release programme was extracted from the area of the dispersal. The data was projected across all countries where the parasitoid has been released and validated. In Kenya, the model showed that F. arisanus had covered a total area of 50.34 km2 from the initial point of open field release; and at the continental scale, the model predicted that the parasitoid had covered a total area of 229.97 km2. The model estimated that 351,855 and 3,731,330 households had directly benefited from the release of F. arisanus between 2013 and 2018 in Kenya and at the continental level, respectively. The study's outcome is appropriate for providing feedback information on the impact of CBC to government and development partners to assist in making informed decisions on technological interventions. [ABSTRACT FROM AUTHOR]

• In this perspective paper we address the concept of pre-emptive biological control as a novel approach to enhance biocontrol preparedness. • We highlight the importance of pre-emptive biological control and provide examples of pre-emptive biological control programmes conducted, or currently underway, against different high-risk pests. • We define a set of aspects that should be considered when selecting a suitable target pest for pre-emptive biocontrol risk assessment. • We provide a set of guidelines and a decision framework to assess the feasibility of conducting pre-emptive risk assessment for candidate biological control agents against high-risk arthropod pests. • We comment on how the proposed guidelines and decision framework will provide biocontrol practitioners with a suitable tool to assess if biocontrol risk assessment against a high-risk pest could be initiated pre-emptively. Non-native invasive arthropod species threaten biodiversity and food security worldwide, resulting in substantial economic, environmental, social and cultural costs. Classical biological control (CBC) is regarded as a cost-effective component of integrated pest management programmes to manage invasive arthropod pests sustainably. However, CBC programmes are traditionally conducted once a pest has established in a new environment, and invariably all research needed to achieve approval to release a biological control agent can take several years. During that time, adverse impacts of the pest accelerate. A pre-emptive biocontrol approach will provide the opportunity to develop CBC for invasive pests before they arrive in the country at risk of introduction and therefore enhance preparedness. A critical aspect of this approach is that risk assessment is carried out in advance of the arrival of the pest. Implementing pre-emptive biocontrol risk assessment means that natural enemies can be selected, screened in containment or abroad and potentially pre-approved prior to a pest establishing in the country at risk, thus improving CBC effectiveness. However, such an approach may not always be feasible. This contribution defines the fundamental prerequisites, principles, and objectives of pre-emptive biocontrol risk assessment. A set of guidelines and a decision framework were developed, which can be used to assess the feasibility of conducting a pre-emptive risk assessment for candidate biological control agents against high-risk arthropod pests. [ABSTRACT FROM AUTHOR]

• We reviewed current practice for selecting plant cultivars for host-specificity test lists. • We found cultivar selection and testing is under-reported in peer-reviewed papers. • We propose a decision tool for selecting crop and ornamental cultivars. • The tool considers past testing, cultivar exposure, phylogeny, and sampling capacity. • The decision tool improves transparency, reproducibility, and defensibility of test lists. Classical biological control is important for long-term, sustainable management of invasive species such as weeds. To be acceptable for introduction, new biocontrol agents must not damage crops, native plants, or other valued non-target species. Host-specificity experiments inform risk assessment of new biocontrol agents by prioritising and testing non-target plant species. Susceptibility to damage can also vary between cultivars of the same species, yet current protocols for the selection of test plant species inadequately address cultivar differences. Poor selection increases the risk of failing to detect non-target damage. We developed criteria for prioritising cultivars and a process chart (the 'decision support tool') to guide the selection of cultivars for biological control host-specificity testing. We reviewed and documented current cultivar selection practice published in prominent biological control journals and government documents to further explore current best practice for cultivar selection. To demonstrate the utility of the tool, we then applied the decision support tool to a complex host-specificity testing case study. In our review, most papers either did not mention cultivars of the cultivated plant species being tested, or they provided incomplete descriptions of cultivars without explaining omissions. Only one of 29 papers fully described the method for selecting and prioritising cultivars and reported the results for each cultivar tested. Our application of the process chart to a potato testing case study generated a feasible short-list of cultivars which can be scrutinized and updated. We showed how selections could be made through a collaborative and transparent process involving key stakeholders and decision makers. We have identified an example of under-reporting in classical biological control which, if not addressed, could impede progress in the sustainable management of invasive species. The decision support tool we developed has broad application in weed biological control risk assessment. We demonstrated that the decision tool is easy to use, can account for uncertainty, is adaptable to different species, and is suitable for both small and large cultivar groups irrespective of complexity. Our approach will result in more transparent, defensible, and reproducible cultivar selection practices, leading to greater confidence in biological control risk assessments. [ABSTRACT FROM AUTHOR]

• Selected recent biocontrol successes in Hawaii are reviewed. • Current trends show improved perceptions of biocontrol in Hawaii. • Numbers of biocontrol introductions in Hawaii remain low, in large part because of a lack of quarantine facilities. • The need for a multi-agency biocontrol research facility in Hawaii is underscored. Hawaii has a long history of classical biological control research and implementation. Many successes have been achieved in suppressing invasive insect species and plants though the introduction of insect and plant pathogenic natural enemies. This review paper details selected recent introductions and discusses selected cases highlighting successes with highly impactful invasive species control in diverse environments. The current state of biological control in Hawaii is discussed, including recent trends in numbers of species released, concerns about non-target impacts, and how these are addressed. Research on the biological aspects is thorough, but the ability to expand research to address continuing invasive species issues is constrained largely by infrastructure limitations. Urgent research needs for continued biological control research are identified. [ABSTRACT FROM AUTHOR]

[Display omitted] • Thrips chose flush foliage over reproductive tissues. • In the absence of flush foliage, thrips chose reproductive tissues. • Thrips directly damage host reproductive tissues and survive to adulthood. • Tissues differed in their volatile constituents. The biological control agent, Pseudophilothrips ichini, is being released for control of Brazilian peppertree, Schinus terebinthifolia (Anacardiaceae), an invasive weed of natural and agricultural areas of California, Florida, Hawaii, and Texas (USA). The thrips larvae and adults feed on flushed leaves and stems that are produced during the vegetative season of the host. However, during the reproductive season from September to December in Florida, few flushing leaves are available as resources are shunted to plant reproduction. As field releases were being implemented, thrips were found feeding and damaging immature fruits and flowers of their host. We hypothesized that the thrips used volatile organic compounds produced by reproductive tissues to locate and feed on these tissues. When examined under laboratory choice tests, individual thrips or groups of either 20 adults or larvae, chose flushing leaves over all reproductive tissues, female flowers, male flowers, and immature fruit. However, to simulate seasons when few flushing leaves were available, additional choice tests were conducted where flushing leaves were omitted, and only reproductive tissues and a filter paper control were included. Individual thrips or groups of either 20 adults or larvae selected all reproductive tissues over controls. When presented with a choice between immature and mature fruit, thrips chose immature fruit. Thrips caused significant damage to live female flowers, male flowers, and immature fruit, and thrips survival rates were similar when fed flush leaves, female flowers, or male flowers. The thrips responses could be tied to VOC production, which significantly varied among tissue types. Volatile blends from flush leaves that include DMNT, Terpinolene, and δ-Elemene may attract P. ichini whereas those that repel them include α-Thujene, α-Pinene, β-Pinene, Camphene, and β-Phellandrene. These results suggest P. ichini has a flexible feeding strategy and exploits Brazilian peppertree reproductive tissues when few flushing tips were available. Further they suggest thrips feeding will have direct impacts on Brazilian peppertree reproduction. [ABSTRACT FROM AUTHOR]

• PAT stress altered the proteome of M. guilliermondii. • PAT up-regulated proteins related to drug resistance and antioxidant stress. • PAT up-regulated proteins related to multidrug transporter and transporter. Meyerozyma guilliermondii is an antagonistic yeast; our research team has recently reported its biocontrol activities against blue mold decay of pears and strong patulin (PAT) reduction ability in vitro. PAT is a harmful mycotoxin produced by some species of Penicillium , Aspergillus , and Byssochlamys. The PAT degradation process and molecular mechanism(s) of M. guilliermondii remain unclear. The data-independent acquisition (DIA) strategies promise a comprehensive, reproducible, digital, qualitative and quantitative record of the proteins present in a sample. Differentially expressed proteins accompanying PAT degradation in M. guilliermondii were observed to investigate PAT reduction mechanisms. The comparative proteomic analysis of M. guilliermondii showed that 136 proteins were up-regulated and 122 were down-regulated upon PAT degradation. The M. guilliermondii's regulation of PAT response mainly includes the up-regulation of (1) growth and reproduction-related protein expression, (2) transcription and translation-related protein expression, (3) resistance-related protein expression, (4) multidrug transporters, (5) anti-oxidative stress-related proteins, (6) the cell wall and cell membrane production-related proteins, and (7) PAT degradation-related protein expression. This paper analyzed M. guilliermondii's molecular response and regulation upon PAT reduction at the gene and protein expression levels. Our results provide a solid foundation for PAT control in fruits and their products by antagonistic yeasts. [ABSTRACT FROM AUTHOR]

• S. cerevisiae NJ-1 VOCs isolated from pomace of Ficus carica were used as biocontrol agents to against A. flavus. • VOCs has a strong inhibitory effect on the growth and production of aflatoxin. • The cell membrane is the potential target of S. cerevisiae NJ-1 VOCs. • S. cerevisiae NJ-1 VOCs contain alcohols, esters and other substances. Aspergillus flavus is capable of producing highly toxic aflatoxins that can infest grains, cereals and nuts, causing serious economic losses and food safety concerns. Therefore, it is especially necessary to study safe and efficient biological control methods. In this paper, an edible strain of Saccharomyces cerevisiae NJ-1 was isolated from pomace of Ficus carica , the inhibitory effects of S. cerevisiae NJ-1 volatile organic compounds (VOCs) on the growth and aflatoxin production of A. flavus were studied, and the mechanisms of inhibitory effects were initially investigated. The results revealed that the inhibitory effects of S. cerevisiae NJ-1 VOCs on the growth, sporulation, and conidial germination of A. flavus varied significantly with the preculture time. Scanning electron microscopy (SEM) images showed that the morphology of the mycelium of A. flavus treated with VOCs was distorted. Meanwhile, the absorbance at 260 nm and 280 nm had a significant increasing trend, which indicated that the cell membrane was one of the action targets of S. cerevisiae NJ-1 VOCs. A total of nine compounds were identified from S. cerevisiae NJ-1 VOCs by headspace solid-phase microextraction gas chromatography (GC/MS). Among them, 3-methyl-1-butanol showed a significant inhibitory effect on A. flavus and may play an important role in the inhibitory effect of NJ-1 VOCs. The study showed that S. cerevisiae NJ-1 VOCs have great potential to be developed as biopesticides for the control of A. flavus. [ABSTRACT FROM AUTHOR]

• Climate change is expected to worsen GAS infestation and threaten food security. • Entomopathogenic fungi and nematodes are potential GAS biological controls. • Integrated and precision pest management improved pest monitoring system. Golden apple snails (GAS) (Pomacea spp.) is one of the major pests that rampantly invaded many countries and brought a heavy bloom to agricultural cultivation. Their invasion had resulted in huge crop damage and ultimately caused massive economic loss. For the past few decades, many strategies had been developed to overcome the GAS infestation. Among all the strategies, chemical synthetic molluscicides had been the mainstay within the farmer community. Despite their effectiveness in controlling the GAS infestation, extensive use of chemical molluscicides has negative impacts on humans, non-targeted organisms, and the environment. Climate change is expected to hasten the reproduction of GAS, necessitating the development of more sustainable GAS mitigation strategies. This paper examines the current stage of GAS invasion and its implications for global rice production. This review also includes an in-depth discussion of the various potential biological based strategies involved in pest management, and the recent technological breakthroughs in entomopathogenic nematodes and entomopathogenic fungi as molluscicides, integrated pest management, and precision pest management. To summarize, this review provides a potential trend in the use of biocontrol as a substitute for chemically manufactured synthetic molluscicides for the sustainable management of GAS. [ABSTRACT FROM AUTHOR]

• A compound library was built based on the semiochemicals derived from flowers, intact plants, herbivore-attacked plants, and insects in the orchard habitats. • Trichogramma dendrolimi was attracted to 17 volatile compounds when using a Y-tube olfactometer and EAG technology. • Two formulations comprising methyl salicylate and benzaldehyde and supplemented with linalool oxide or cis -3-hexenyl caproate (10:3:3) attracted more T. dendrolimi to orchards than positive (methyl salicylate only) and solvent controls. • In addition to T. dendrolimi , these same formulas also seem to attract other natural enemies in the orchards such as Syrphidae and ladybeetles. Trichogramma dendrolimi Matsumura (Hymenoptera: Trichogrammatidae) is one of the most important parasitic natural enemies of Grapholita molesta (Busck) (Lepidoptera: Tortricidae) in peach and pear orchards. The artificial rearing T. dendrolimi have been widely used in biological control programs in recent years. However, its actual parasitic effect on the pest in the field is less, so it is important to develop attractants to increase the parasitic efficiency of the parasitoids. T. dendrolimi can be easily attracted by semiochemicals derived from flowers, intact plants, herbivore-attacked plants, and insects in its orchard habitats. In this paper, 73 semiochemicals were evaluated as potential attractants at three concentrations (0.1 mg/mL, 1 mg/mL, and 10 mg/mL) to T. dendrolimi by Y-tube olfactometer bioassays and Electroantennogram (EAG) technology, and then the mixtures of active individual compounds were further tested and evaluated in the field. As a result, 17 individual compounds showed attractive bioactivity to T. dendrolimi. Interestingly, when methyl salicylate and benzaldehyde mixed with linalool oxide or cis -3-hexenyl caproate in a volume ratio of 10:3:3 respectively showed excellent attractant bioactivity for T. dendrolimi in the orchard field. Thus, introducing such parasitoid attractants in orchard habitat may improve the biological control effect to pests. [ABSTRACT FROM AUTHOR]

• P-amino benzoic acid and octyl methoxycinnamate are not toxic to Steinernema feltiae. • UV absorbing chemicals protect Steinernema feltiae from adverse effects up to 12 h. • A desiccant and UV protectant mix prolongs the ability of Steinernema feltiae to infect insects on leaves. • Steinernema feltiae mixed with desiccant and UV protectants increases potential for foliar pest control. Entomopathogenic nematodes (EPNs) are obligate parasites of insects. EPNs generally have a broad host range, are easily mass reared, and can kill some insects within 48 h. EPNs are safe for vertebrates, plants, and other non-target organisms. However, EPNs have disadvantages that make them less effective against foliar insect pests such as sensitivity to desiccation, ultraviolet (UV) radiation, and high temperatures. The goal of this research was to improve the efficacy of aboveground application of Steinernema feltiae by protecting the nematodes against desiccation and UV radiation. The objectives were to evaluate the effect of UV chemical protectants on S. feltiae viability and demonstrate enhanced insect control with S. feltiae formulated to protect them against UV radiation and desiccation. The UV radiation protectant chemicals P-amino benzoic acid (PABA), octyl methoxycinnamate (OMC), Congo red, titanium dioxide, and zinc oxide were not toxic to mealworm larvae nor the EPNs. PABA, OMC, Congo red, titanium dioxide, and zinc oxide protected Infective Juveniles (IJ) of S. feltiae exposed to UV light for 0, 4, 8 and 12 hrs. After 48 hrs exposure, PABA afforded the greatest protection to S. feltiae compared to other chemicals. OMC provided the second greatest protection to the S. feltiae compared to other chemicals. The UV protectants PABA and OMC were individually combined with Barricade® fire gel, a desiccant protectant, and IJs of S. feltiae were added to the mixture. The IJs were exposed to full spectra UV light in the laboratory for up to 12 hrs before introduction of a mealworm host. The subsequent number of dead mealworm larvae on filter paper or on detached leaves was greatest in the combination treatments of OMC + Barricade and PABA + Barricade and lowest in water controls demonstrating the protection afforded to S. feltiae. The survival of S. feltiae can be enhanced when applied with a desiccant protectant such as Barricade and a chemical such as PABA or OMC to protect against UV radiation. The protection afforded to the IJ by these chemicals allows for greater infection and mortality of target insect pests. The formulation of IJs with desiccant and UV radiation protection will allow the greater use of S. feltiae for the management of foliar insect pests. [ABSTRACT FROM AUTHOR]

• The cabbage stem flea beetle is an economically important pest of oilseed rape. • Control using only conventional insecticides often ineffective. • Entomopathogens and natural enemies are potentially effective biocontrol agents. • Additional research needed to create integrated pest management programs. • Research gaps: need to understand interactions between agents to optimize control. The cabbage stem flea beetle (CSFB 1 1 CSFB: cabbage stem flea beetle.) Psylliodes chrysocephala Linnaeus is the most important pest of oilseed rape (Brassica napus) crops in Europe. Control has become more difficult since the European Union ban in 2013 on the use of neonicotinoid seed treatments. This situation is made more challenging by the development of resistance to pyrethroid insecticides, the only remaining conventional synthetic insecticides with which to control CSFB. The purpose of this paper is to review the potential of biological alternatives to the use of synthetic pesticides for the control of the CSFB. Only a small number of studies have investigated biological control agents against CSFB itself. More research has, however, been published on two other, closely related chrysomelid pests of brassica crops that have similar life cycles, namely the crucifer flea beetle Phyllotreta cruciferae and the striped flea beetle Phyllotreta striolata , which enable us to extrapolate reasonably across to CSFB. The biological control agents investigated include entomopathogenic fungi (EPF 2 2 EPF: entomopathogenic fungi.) such as Metarhizium anisopliae and Beauveria bassiana , entomopathogenic nematodes (EPN 3 3 EPN: entomopathogenic nematode.) such as Steinernema feltiae and Steinernema carpocapsae , parasitoids such as Microctonus brassicae and predators such as the ground beetle Trechus quadristriatus. Results vary depending on the setting (laboratory versus field), but several biological control agents investigated resulted in CSFB mortality greater than 50% under laboratory conditions. The biological control of the CSFB shows potential as a viable alternative to the use of conventional synthetic insecticides. Nonetheless, many research gaps remain, as current research has focused largely on crucifer flea beetle and striped flea beetle, with comparatively few studies investigating the potential of biological controls against the CSFB. The research published to date on CSFB has been limited to a small number of species of EPN and EPF with little work investigating the potential of parasitoids and predators. More field studies using EPF are required, while in contrast laboratory studies are underrepresented for EPN. Further research is required, testing existing and new strains of fungi and nematodes, exploring the potential of endophytic fungi, enhancing the formulation and application of biological control for use in inundative strategies, and investigating the potential of conservation biological control. Effective biological control agents should ultimately be combined with cultural control methods in Integrated Pest Management (IPM 4 4 IPM: Integrated Pest Management.) systems for the sustainable management of this pest. [ABSTRACT FROM AUTHOR]

• Entomopathogenic nematodes can control tomato leafminer. • Relative humidity affected control by entomopathogenic nematodes. • Different nematode species performed differently, interacting with temperature. • Late instar larvae of the leafminer were easier to control. The South American tomato pinworm, Tuta absoluta (Meyrick) is one of the most serious insect pests of tomato plants. Current control strategies for T. absoluta primarily involve the use of insecticides, but increasing resistance in field populations has prompted research on alternative control measures. Biological control with entomopathogenic nematodes (EPNs) can be an alternative or one component of an Integrated Pest Management programme. In foliar application, EPNs encounter many factors that affect their survival and efficacy. This paper reports investigations into some of these factors for several EPN species; relative humidity (RH), temperature, time required by EPNs to enter a leaf and number of applications in whole leaf bioassays on tomato leaves. RH was the most important factor; EPNs efficacy and survival decreased as RH declined. Steinernema feltiae was the most effective species followed by Steinernema carpocapsae then Heterorhabditis bacteriophora. Steinernema carpocapsae survived better at low RH than S. feltiae. The two Steinernema species induced similar mortality at 25 °C, but S. feltiae was more virulent at lower temperatures (15 and 20 °C) while S. carpocapsae was more virulent at higher temperatures (30 and 35 °C). First and second instar larvae of T. absoluta required more applications compared to third and fourth instar larvae. The species of EPN used to control T. absoluta requires careful selection in relation to the temperature and relative humidity environment of the crop to maximise efficacy. [ABSTRACT FROM AUTHOR]