Tim Haye

Biology, Ecology, and Management of Brown Marmorated Stink Bug (Hemiptera: Pentatomidae)

Brown marmorated stink bug, Halyomorpha halys Stal, is an invasive, herbivorous insect species that was accidentally introduced to the United States from Asia. First discovered in Allentown, PA, in 1996, H. halys has now been reported from at least 40 states in the United States. Additional invasions have been detected in Canada, Switzerland, France, Germany, Italy, and Lichtenstein, suggesting this invasive species could emerge as a cosmopolitan pest species. In its native range, H. halys is classified as an outbreak pest; however, in North America, H. halys has become a major agricultural pest across a wide range of commodities. H. halys is a generalist herbivore, capable of consuming >100 different species of host plants, often resulting in substantial economic damage; its feeding damage resulted in US

Current SWD IPM tactics and their practical implementation in fruit crops across different regions around the world

37 million of losses in apple in 2010, but this stink bug species also attacks other fruit, vegetable, field crop, and ornamental plant species. H. halys has disrupted integrated pest management programs for multiple cropping systems. Pesticide applications, including broad-spectrum insecticides, have increased in response to H. halys infestations, potentially negatively influencing populations of beneficial arthropods and increasing secondary pest outbreaks. H. halys is also challenging because it affects homeowners as a nuisance pest; the bug tends to overwinter in homes and outbuildings. Although more research is required to better understand the ecology and biology of H. halys , we present its life history, host plant damage, and the management options available for this invasive pest species.

Range expansion of the invasive brown marmorated stinkbug, Halyomorpha halys: an increasing threat to field, fruit and vegetable crops worldwide

After its arrival in 2008, the Spotted Wing Drosophila (SWD), Drosophila suzukii, has emerged as a harmful invasive insect pest in North America and Europe. This highly polyphagous pest is a major threat to many economically important fruit crops and is also known to develop on a wide variety of natural host plants. In Asia, Europe and North America, different control measures are applied against SWD, such as chemical, biological, and cultural control. Current controls of SWD rely primarily on the application of insecticides, but cultural management tactics such as sanitation and the use of nets provide a good alternative in some crops. Biological control measures, such as conservation of existing natural enemies in invaded areas, introduction of specialized larval parasitoids from Asia for classical biological control and the use of indigenous parasitoids for augmentative control, are currently being investigated and may become an important management tool in the near future for an area-wide control of SWD.

Non-crop plants used as hosts by Drosophila suzukii in Europe

The brown marmorated stink bug, Halyomorpha halys (Hemiptera: Pentatomidae), has emerged as a harmful invasive insect pest in North America and Europe in the 1990s and 2000s, respectively. Native to eastern Asia, this highly polyphagous pest (>120 different host plants) is spreading rapidly worldwide, notably through human activities. The increasing global importance of the pest suggests that more coordinated actions are needed to slow its spread and mitigate negative effects in invaded areas. Prevention of large-scale outbreaks will require accurate identification and effective mitigation tools to be rapidly developed and widely implemented. In this short review, we update the current distribution of H. halys, discuss potential geographic range expansion based on passive and active dispersal and provide insight on the economic, environmental and social impact associated with H. halys.

A single-step multiplex PCR assay for the detection of European Peristenus spp., parasitoids of Lygus spp.

The invasive spotted wing drosophila Drosophila suzukii, a fruit fly of Asian origin, is a major pest of a wide variety of berry and stone fruits in Europe. One of the characteristics of this fly is its wide host range. A better knowledge of its host range outside cultivated areas is essential to develop sustainable integrated pest management strategies. Field surveys were carried out during two years in Italy, the Netherlands and Switzerland. Fruits of 165 potential host plant species were collected, including mostly wild and ornamental plants. Over 24,000 D. suzukii adults emerged from 84 plant species belonging to 19 families, 38 of which being non-native. Forty-two plants were reported for the first time as hosts of D. suzukii. The highest infestations were found in fruits of the genera Cornus, Prunus, Rubus, Sambucus and Vaccinium as well as in Ficus carica, Frangula alnus, Phytolacca americana and Taxus baccata. Based on these data, management methods are suggested. Ornamental and hedge plants in the vicinity of fruit crops and orchards can be selected according to their susceptibility to D. suzukii. However, the widespread availability and abundance of non-crop hosts and the lack of efficient native parasitoids suggest the need for an area-wide control approach.

Occurrence, genetic diversity, and potential pathways of entry of Halyomorpha halys in newly invaded areas of Canada and Switzerland

Abstract Lygus Hahn (Hemiptera: Miridae) are serious pests of agricultural and greenhouse crops throughout North America. In Europe, bivoltine Peristenus Förster (Hymenoptera: Braconidae) species have a significant impact on Lygus populations. Release and establishment of European P. digoneutis Loan in Lygus lineolaris (Palisot de Beauvois) populations in northeastern USA has renewed interest in the intended liberation of European parasitoids for Lygus control in Canada. Accurate identification of natural enemies is the cornerstone of biological control but conventional methods for identifying Peristenus species and estimating parasitism rates rely on tedious and time-consuming dissection and rearing methods. The present study describes species-specific PCR primers for three species of Peristenus, and the use of a multiplex PCR assay to detect P. digoneutis and P. stygicus Loan eggs and larvae from Lygus rugulipennis Poppius nymphs. Results indicate that the primers amplify uniquely sized, species-specific PCR products for the three species and are capable of detecting single eggs in parasitized nymphs within 3 days post-parasitism. Using a multiplex PCR assay, the primers maintain specificity and sensitivity, and allow detection of each of the three species in a single reaction. Although molecular diagnostics have previously been used in the identification of parasitoids and estimation of parasitism rates, this is the first time a single-step multiplex PCR protocol has been described.

A review of the natural enemies of beetles in the subtribe Diabroticina (Coleoptera: Chrysomelidae): implications for sustainable pest management

Halyomorpha halys has recently established in countries outside of its Asian area of origin. In the North Eastern USA, this pest causes severe economic loss in agricultural crops. Breeding populations have been confirmed in Switzerland and Canada; however, their pathways of entry and genetic diversity remain unknown. To determine invasion pathways and source population(s), the diversity of specimens from Asia, North America, and Europe was investigated. Genetic diversity in Asia was higher than that in the Canada and Switzerland. Although three haplotypes were detected among Canadian H. halys, one haplotype dominated. In contrast, two out of three haplotypes were found frequently among Swiss samples. Based on molecular data and interception records it appears likely that H. halys in Canada is derived from the movement of established US populations. Further, North American populations likely originated from the Hebei/Beijing regions of China. The area of origin of the Swiss samples remains unclear. Although the dominant haplotype in Switzerland was consistent with Asian samples collected in the Hebei and Beijing provinces, it was not the dominant haplotype in these regions and further sampling is necessary to its confirm the distribution and abundance in the area of origin. The remaining two haplotypes were unique to Switzerland and no matches were found among our Asian samples. Interestingly, no haplotypes were shared between the North American and Swiss samples, indicating that the two invasions were separate and distinct events and did not result from the movement of goods and materials between USA and Europe.

A molecular diagnostic tool for the preliminary assessment of host-parasitoid associations in biological control programmes for a new invasive pest.

Abstract Diabroticina is a speciose subtribe of New World Chrysomelidae (Subfamily Galerucinae: Tribe Luperini) that includes pests such as corn rootworms, cucumber beetles and bean leaf beetles (e.g. Diabrotica, Acalymma, Cerotoma species). The evolution and spread of pesticide resistance, the European invasion of Diabrotica v. virgifera LeConte, and possible development of resistance due to the large-scale deployment of Diabrotica-active Bt maize in North America have generated a sense of urgency in developing biological control options against Diabroticina pests. In the present study, we review available knowledge on biological control options, including 290 publications on natural enemy–Diabroticina associations in the New World. Several natural enemy species or groups appear to be promising candidates for control strategies with different ecological rationales. We propose that future research should pursue: (1) development of inundative biological control products, particularly mass-produced entomopathogenic nematodes and fungi, (2) understanding of specific natural enemies of Diabroticina larvae throughout the Americas and of adults particularly in higher altitudes of Central America or northern South America including potential classical biological control agents against D. v. virgifera; (3) enhancement of natural enemies through cultural practices, i.e., reduced tillage, reduced weed control, cover crops, diversified crop rotations or soil amendments. Research and action must be coordinated to accelerate the exploration of biological control options.

The potential global distribution of the brown marmorated stink bug, Halyomorpha halys , a critical threat to plant biosecurity

Evaluation of host–parasitoid associations can be tenuous using conventional methods. Molecular techniques are well placed to identify trophic links and resolve host–parasitoid associations. Establishment of the highly invasive brown marmorated stink bug, Halyomorpha halys (Hemiptera: Pentatomidae), outside Asia has prompted interest in the use of egg parasitoids (Hymenoptera: Scelionidae) as biological control agents. However, little is known regarding their host ranges. To address this, a DNA barcoding approach was taken wherein general PCR primers for Scelionidae and Pentatomidae were developed to amplify and sequence >500‐bp products within the DNA barcoding region of the cytochrome oxidase I (COI) gene that would permit the identification of key players in this association. Amplification of DNA from Pentatomidae and Scelionidae was consistent across a broad range of taxa within these families, and permitted the detection of Scelionidae eggs within H. halys 1 h following oviposition. In laboratory assays, amplification and sequencing of DNA from empty, parasitized eggs was successful for both host (100% success) and parasitoid (50% success). When applied to field‐collected, empty egg masses, the primers permitted host identification in 50–100% of the eggs analysed, and yielded species‐level identifications. Parasitoid identification success ranged from 33 to 67% among field‐collected eggs, with genus‐level identification for most specimens. The inability to obtain species‐level identities for these individuals is due to the lack of coverage of this taxonomic group in public DNA sequence databases; this situation is likely to improve as more species are sequenced and recorded in these databases. These primers were able to detect and identify both pentatomid host and scelionid parasitoid in a hyperparasitized egg mass, thereby clarifying trophic links otherwise unresolved by conventional methodology.

Indigenous arthropod natural enemies of the invasive brown marmorated stink bug in North America and Europe

The brown marmorated stinkbug, Halyomorpha halys is a highly polyphagous invasive insect, which has more than 300 reported hosts, including important horticultural crops. It has spread to every Northern Hemisphere continent, most recently to Europe. Whilst there have been no reports of incursions into Southern Hemisphere countries, there have been many interceptions associated with trade and postal goods. We modelled the potential distribution of H. halys using CLIMEX, a process-oriented bioclimatic niche model. The model was validated with independent widespread distribution data in the USA, and more limited data from Europe. The model agreed with all credible distribution data. The few exceptions in the distribution dataset appeared to be transient observations of hitchhikers, or were found at the edge of the range, in regions with topographic relief that was not captured in the climatic datasets used to fit and project the model. There appears to be potential for further spread in North America, particularly in central and southern states of the USA. In Europe, there is substantial potential for further spread, though under historical climate the UK, Ireland, Scandinavia and the Baltic states of Estonia, Lithuania and Latvia appear not to be at risk of establishment of H. halys. In the Southern Hemisphere, regions with moist tropical, sub-tropical, Mediterranean and warm-temperate climates appear to be at substantial risk on each continent. The threats are greatest in prime horticultural production areas.