Entomophagous biological control agents
Aeschlimann J.P. (1995). Lessons from post-release investigations in classical biological control: the case of Microctonus aethiopoides Loan (Hym., Braconidae) introduced into Australia and New Zealand for the biological control of Sitona discoideus Gyllenhal (Col., Curculionidae). Pp. 75-83 In: Biological Control: Benefits and Risks, H.M.T. Hokkanen and J.M. Lynch (Ed.) Cambridge University Press, Cambridge, UK.
Asquith A. and Miramontes E. (2001). Alien parasitoids in native forests: the ichneumonoid wasp community in Hawaiian rainforest. Pp. 54-67 In: Balancing nature: assessing the impact of importing non-native biological control agents (an international perspective), J.A. Lockwood, F.G. Howarth and M. Purcell (Ed.) Entomological Society of America, Lanham, Maryland.
Babendreier D. and Bigler F. (2005).
How to assess non-target effects of polyphagous biological control agents: Trichogramma brassicae as a case study.
Pp. 603-610 In: Second International Symposium on Biological Control of Arthropods, Davos, Switzerland, 12-16 September, 2005, M.S. Hoddle (Ed.) United States Department of Agriculture, Forest Service, Washington.
The risk assessment conducted for Trichogramma brassicae (Hymenoptera: Trichogrammatidae), an egg parasitoid used for control of the European corn borer in European countries is discussed. The main factors investigated were the potential of establishment, acceptance and parasitism of non-target butterflies under laboratory, field-cage and field conditions, the searching efficiency in non-target habitats, the dispersal capacities and the potential for effects on other natural enemies in maize. Although high parasitism of non-target butterflies and other natural enemies were observed under laboratory conditions, very few eggs of non-target species were attacked in the field, possibly because of low host searching efficiency, and limited parasitoid dispersal. It was concluded that the possibility of using invertebrate agents with a broad host range in inundative biological control should not be excluded, although a thorough environmental risk assessment should be performed prior to release.
Babendreier D., Kuske S. and Bigler F. (2003).
Parasitism of non-target butterflies by Trichogramma brassicae Bezdenko (Hymenoptera: Trichogrammatidae) under field cage and field conditions.
Biological Control 26: 139-145.
The egg parasitoid Trichogramma brassicae has been inundatively released to control the European corn borer, Ostrinia nubilalis Hübner, in maize. Non-target parasitism of butterfly eggs by T. brassicae in field cages and under field conditions in Switzerland was investigated. Although the tested non-target butterflies were all attacked under semi-field and field conditions, it was concluded that effects on non-target butterflies due to mass released T. brassicae are minimal.
Balciunas J.K., Burrows D.W. and Purcell M.F. (1996). Comparison of the physiological and realized host-ranges of a biological control agent from Australia for the control of the aquatic weed, Hydrilla verticillata. Biological Control 7: 148-158.
Barratt B.I.P., Blossey B. and Hokkanen H.M.T. (2006).
Post-release evaluation of non-target effects of biological control agents.
Pp. 166-186 In: Environmental Impact of Arthropod Biological Control: Methods and Risk Assessment, U. Kuhlmann, F. Bigler and D. Babendreier (Ed.) CABI Bioscience, Delemont, Switzerland.
This paper deals with weed biological control agents, pathogens and parasitoids.
Barratt B.I.P., Evans A.A., Ferguson C.M., McNeill M.R. and Addison P. (2000).
Phenology of native weevils (Coleoptera: Curculionidae) in New Zealand pastures and parasitism by the introduced braconid, Microctonus aethiopoides Loan (Hymenoptera: Braconidae).
New Zealand Journal of Zoology 27: 93-110.
The phenology of native weevils pasture sites in Otago, Canterbury and Waikato was studied by monthly sampling to record reproductive status and incidence of parasitism by introduced braconid parasitoids in the genus Microctonus. Most parasitism occurred after the main reproductive period of entimine weevils in spring, but a putative second generation in some species might be more affected by parasitoid attack. A native rhytirhinine species, Steriphus variabilis, differed from the entimines because adults emerged in autumn and spring, and may be bivoltine.
Barratt B.I.P., Ferguson C.M., Bixley A.S., Crook K.E., Barton D.M. and Johnstone P.D. (2007).
Field parasitism of nontarget weevil species (Coleoptera : Curculionidae) by the introduced biological control agent Microctonus aethiopoides Loan (Hymenoptera : Braconidae) over an altitude gradient.
Environmental Entomology 36: 826-839
The parasitoid, Microctonus aethiopoides Loan (Hymenoptera: Braconidae) was introduced into New Zealand in 1982 to control the alfalfa pest, Sitona discoideus Gyllenhal (Coleoptera: Curculionidae). Studies have shown that a number of nontarget weevil species are attacked in the field by this parasitoid. A field study was carried out over 6 years to investigate nontarget parasitism by M. aethiopoides over an altitudinal sequence from the target host habitat (alfalfa) into native grassland. Weevil densities were estimated, species identified, and dissections carried out to determine reproductive status and parasitism. Seven nontarget weevil species were found to be parasitized. Substantial nontarget parasitism was found at only one of the three locations, with up to 24% parasitism of a native weevil, Nicaeana fraudator Broun (Coleoptera: Curculionidae), recorded. Results are discussed in relation to weevil phenology.
Barratt B.I.P., Oberprieler R.G., Ferguson C.M. and Hardwick S. (2005).
Parasitism of the lucerne pest Sitona discoideus Gyllenhal (Coleoptera: Curculionidae) and non-target weevils by Microctonus aethiopoides Loan (Hymenoptera: Braconidae) in south-eastern Australia, with an assessment of the taxonomic affinities of non-target hosts of M. aethiopoides recorded from Australia and New Zealand.
Australian Journal of Entomology 44: 192-200.
A survey of weevils found in and near lucerne in south-eastern Australia was carried out to investigate whether similar non-target parasitism was occurring in Australia as in NZ. A single incidence of parasitism of a species of an Australian native weevil Prosayleus sp. by M. aethiopoides was recorded. No parasitism of any other weevil species was observed. The taxonomic affinities between Sitona and native Australian and New Zealand weevils are discussed, concluding that non-target host range in M. aethiopoides may be determined more by ecological factors than by taxonomic affinities among its hosts.
Barron M.C., Barlow N.D. and Wratten S.D. (2003).
Non-target parasitism of the endemic New Zealand red admiral butterfly (Bassaris gonerilla) by the introduced biological control agent Pteromalus puparum.
Biological Control 27: 329-335.
The New Zealand red admiral butterfly has long been recognised as a non-target host for the introduced biological control agent Pteromalus puparum but its impact has never been quantified. Data were collected to construct a partial life table for B. gonerilla. Egg parasitism by an unidentified Telenomus (scelionid) was 95%. P. puparum parasitized 14% of B. gonerilla pupae sampled. However, pupal parasitism by the self-introduced Echthromorpha intricatoria (F.) (Hymenoptera: Ichneumonidae), was higher at 26%. It is concluded that P. puparum has permanently enhanced mortality in B. gonerilla, but the level of mortality is low relative to egg parasitism by Telenomus sp. and pupal mortality due to E. intricatoria parasitism.
Bigler, F., Babendreier, D. and van Lenteren, J.C. (2010). Risk Assessment and non-target effects of egg parasitoids in biological control. Pp. 413-442 In: Egg Parasitoids in Agroecosystems with Emphasis on Trichogramma, F. L. Consoli, J. R. P. Parra and R. A. Zucchi (Eds.) Springer, Dortrecht, Netherlands.
Boettner G.H., Elkinton J.S. and Boettner C.J. (2000).
Effects of a biological control introduction on three nontarget native species of saturniid moths.
Conservation Biology 14: 1798-1806.
The nontarget effects of a generalist parasitoid fly, Compsilura concinnata (Diptera: Tachinidae), that has been introduced as a biological control agent against 13 pest species were examined. Results suggested that reported declines of silk moth populations in New England may have been caused by C. concinnata.
Catherine G.W., Schulthess F. and Stephane D. (2010.). An association between host acceptance and virulence status of different populations of Cotesia sesamiae , a braconid larval parasitoid of lepidopteran cereal stemborers in Kenya. Biological Control 54: 100-106
Chong J.-H. and Oetting R.D. (2007). Specificity of Anagyrus sp nov nr. sinope and Leptomastix dactylopii for six mealybug species. BioControl 52: 289-308
Cock M.J.W., Murphy S.T., Kairo M.T.K., Thompson .E, Murphy R.J. and Francis A.W. (2016). Trends in the classical biological control of insect pests by insects: an update of the BIOCAT database. Biocontrol. doi:DOI 10.1007/s10526-016-9726-3.
Duan J.J. and Messing R.H. (1996). Response of two Opiine fruit fly parasitoids (Hymenoptera: Braconidae) to the Lantana Gall fly (Diptera: Tephritidae). Environmental Entomology 25: 1428-1437.
Duan J.J. and Messing R.H. (1996).
Effect of two Opiine parasitoids (Hymenoptera: Braconidae) introduced for fruit fly control on a native Hawaiian Tephritid, Trupanea dubautiae (Diptera: Tephritidae).
Biological Control 8: 177-184.
Diachasmimorpha longicaudata and Psyttalia fletcheri are opiine parasitoids introduced into Hawaii for control of Bactrocera dorsalis and Bactrocera cucurbitae, respectively. Both species have been mass-reared and released for research in augmentative biocontrol programs. The potential impact of mass-produced D. longicaudata and P. fletcheri on a native Hawaiian tephritid, Trupanea dubautiae, infesting the flowerheads of Dubautia raillardioides was investigated. The results demonstrated that biological control programs targeted against frugivorous tephritid pests by D. longicaudata and P. fletcheri have no harmful impact on T. dubautiae.
Duan J.J. and Messing R.H. (1998).
Effect of Tetrastichus giffardianus (Hymenoptera: Eulophidae) on nontarget flowerhead-feeding tephritids (Diptera: Tephritidae).
Biological Control 27: 1022-1028.
Laboratory tests and field surveys were conducted in Hawaii to evaluate the impact of a deliberately introduced fruit fly parasitoid, Tetrastichus giffardianus, on 2 nontarget flowerhead-feeding tephritid flies, Trupanea dubautiae and Ensina sonchi. In the laboratory, T. giffardianus were able to parasitize late instars of both T. dubautiae and E. sonchi when they were dissected out of the flower heads, however, no T. dubautiae and few E. sonchi were attacked by T. giffardianus when presented in their respective host flowerheads. So although late instars of both T. dubautiae and E. sonchi are suitable for the physiological development of T. giffardianus progeny, the parasitoid is unlikely to affect either species under natural conditions because the host microhabitats are not suitable for gravid parasitoids to find and oviposit in the fly larvae.
Duan J.J. and Messing R.H. (1999). Evaluating nontarget effects of classical biological control: fruit fly parasitoids in Hawaii as a case study. Pp. 95-109 In: Nontarget effects of biological control introductions, P.A. Follett and J.J. Duan (Ed.) Kluwer Academic Publishers, Norwell, Massachusetts, USA.
Duan J.J., Ahmad M., Joshi K. and Messing R.H. (1996).
Evaluation of the impact of the fruit fly parasitoid Diachasmimorpha longicaudata (Hymenoptera: Braconidae) on a nontarget tephritid, Eutreta xanthochaeta (Diptera: Tephritidae).
Biological Control 8: 58-64.
Field studies were carried out in Hawaii to investigate the effects of the release of Biosteres longicaudatus on Eutreta xanthochaeta, a biological control agent of the weed Lantana camara. In field cages, Bactrocera dorsalis was presented on guavas and lantana twigs with galls. The presence of B. dorsalis or food had minimal effect on visiting and probing of B. longicaudatus and rates of parasitism were very low. It was concluded that an increase in the number of B. longicaudatus will not result in significant losses of E. xanthochaeta or influence the biological control of L. camara.
Duan J.J., Purcell M.F. and Messing R.H. (1996). Parasitoids of non-target tephritid flies in Hawaii: implications for biological control of fruit fly pests. Entomophaga 41: 245-256.
Elkinton J.S., Parry D. and Boettner G.H. (2006).
Implicating an introduced generalist parasitoid in the invasive browntail moth's enigmatic demise.
Ecology 87: 2664-2672.
The parasitoid Compsilura concinnata (tachinid) is considered an example of biological control gone wrong. It was introduced for gypsy moth, Lymantria dispar, and now attacks more than 180 species of native Lepidoptera in North America. It failed to control gypsy moth, data suggest that parasitism by C. concinnata is the cause of the near extinction of another exotic lepidopteran, the browntail moth (Euproctis chrysorrhoea). Despite this beneficial role played by C. concinnata in controlling the browntail moth, the authors do not advocate introduction of generalist biological control agents, which can have unpredictable and far-reaching impacts.
Elkinton, J.S. and Boettner, C.J. (2012).
Benefits and harm caused by the introduced generalist tachinid, Compsilura concinnata, in North America.
Biocontrol 57: 277–288
Compsilura concinnata (Meigen) is a highly generalist tachinid parasitoid that was introduced in the USA to control gypsy moth and browntail moth. The impact on gypsy moth was thought to be minor, although research with experimentally created populations of gypsy moth suggests that it may be more important than previously realized. Studies on browntail moth suggest that C. concinnata is probably the main reason browntail moth disappeared from most of its former range in North America. Research on giant silk moths suggests that C. concinnata has become the major source of mortality among several species and may be responsible for the notable decline in their densities that has occurred over the last century. C. concinnata is considered an example of a generalist natural enemy that should be avoided in classical biological control introductions, yet in the case of browntail moth its effect has been extremely beneficial.
Evans A.A., Barratt B.I.P. and Emberson R.M. (1997).
Field cage and laboratory parasitism of Nicaeana cervina by Microctonus aethiopoides.
Pp. 223-226 In: Proceedings of the 50th New Zealand Plant Protection Conference, M.R. O'Callaghan (Ed.) New Zealand Plant Protection Society Inc.
A study was carried out to compare parasitism of the NZ native weevil Nicaeana cervina Broun by Microctonus aethiopoides Loan in field cage versus laboratory conditions. Total parasitism was 40-55% and 15% in laboratory and field cages, respectively. The level of parasitism obtained in the field cages was similar to that recorded in a natural population nearby.
Evans W.E. and England S. (1996).
Indirect interactions in biological control of insects: pests and natural enemies in alfalfa.
Ecological Applications 6: 920-930.
Trophic interaction between alfalfa weevil, Hypera postica, and its parasitoid Bathyplectes curculionis, along with pea aphid (which produce honeydew, of value to the parasitoid) and ladybird beetles which feed on aphids and H. postica larvae. The results emphasise the complexity of these interactions.
Ferguson C.M., Barratt B.I.P. and Cresswell A.S. (1999). Field parasitism of the weed biological control agent Rhinocyllus conicus by the introduced braconid, Microctonus aethiopoides. Pp. 275 (abstract) In: Proceedings of the 52nd New Zealand Plant Protection Society Conference, M.R. O'Callaghan (Ed.) New Zealand Plant Protection Society.
Ferguson C.M., Cresswell A.S., Barratt B.I.P. and Evans A.A. (1998). Non-target parasitism of the weed biological control agent, Rhinocyllus conicus Froelich (Coleoptera: Curculionidae) by Microctonus aethiopoides Loan (Hymenoptera: Braconidae). Pp. 517-524 In: Pest Management - Future Challenges: Proceedings of the 6th Australasian Applied Entomological Research Conference, M. Zalucki, R. Drew and G. White (Ed.) The Cooperative Research Centre for Tropical Pest Management, Australia.
Ferguson C.M., Kean J.M., Barton D.M. and Barratt B.I.P. (2016).
Ecological mechanisms for non-target parasitism by the Moroccan ecotype of Microctonus aethiopoides Loan (Hymenoptera: Braconidae) in native grassland.
Biological Control 96: 28-38.
The Moroccan ecotype of the braconid parasitoid Microctonus aethiopoides was introduced into New Zealand for biological control of the lucerne pest Sitona discoideus. The parasitoid also attacks several non-target native weevil species found in pasture and also to a lesser extent in native tussock grassland. We carried out a series of laboratory and field experiments, and population modelling to investigate whether the parasitoids were established at low levels on native weevils in tussock grassland, whether S. discoideus was able to survive and support parasitoid development away from lucerne, its normal host plant, or whether parasitism was occurring as a result of spillover from agricultural environments. We found that S. discoideus was able to survive and support parasitoid development on white clover which is commonly found in native grassland. However, the levels of parasitism in weevil species in tussock grassland appeared to be constrained, at least in part, by low temperatures limiting the number of parasitoid generations possible per year and by the frequency of sub-zero temperatures that caused pupal mortality. Projected climate change might reduce this constraint and the implications of this are discussed.
Follett P.A., Johnson M.T. and Jones V.P. (1999). Parasitoid drift in Hawaiian pentatomids. Pp. 77-93 In: Nontarget effects of biological control introductions, P.A. Follett and J.J. Duan (Ed.) Kluwer Academic Publishers, Norwell, Massachusetts, USA.
Gripenberg, S., Hamer, N.I.A., Brereton, T.O.M., Roy, D.B. and Lewis, O.T. (2011).
A novel parasitoid and a declining butterfly: cause or coincidence?
Ecological Entomology 36: 271-281
The small tortoiseshell butterfly (Aglais urticae L.) declined sharply in the U.K. between 2003 and 2008, coinciding with the arrival and spread of a parasitoid, Sturmia bella Meig. (Diptera: Tachinidae), which specialises on nymphalid butterflies. Data from a large-scale butterfly monitoring scheme, and collections of larvae were to assess parasitoid incidence and parasitism frequency. Similar data were compiled for a related butterfly (Inachis io) which is also parasitised by S. bella but which is not declining. Sturmia bella was present in 26% and 15% of the larval groups of A. urticae and I. io, respectively, and now kills more individuals of A. urticae (but not I. io) than any native parasitoid. Results indicated that S. bella causes host mortality in addition to that caused by native parasitoids and that S. bella may be playing a role in the recent decline of A. urticae. Other potential drivers of trends in the abundance of this butterfly may be present.
Haye T., Goulet H., Mason P.G. and Kuhlmann U. (2005).
Does fundamental host range match ecological host range? A retrospective case study of a Lygus plant bug parasitoid.
Biological Control 35: 55-67.
Using the retrospective case study of Peristenus digoneutis (Hymenoptera: Braconidae) introduced in the United States for biological control of native Lygus plant bugs (Hemiptera: Miridae), laboratory and field studies were conducted in the area of origin to evaluate whether the fundamental host range of P. digoneutis matches its ecological host range. To confirm the validity of the fundamental host range, the ecological host range of P. digoneutis in the area of origin was investigated. Peristenus digoneutis was reared from 10 hosts, including three Lygus species and seven non-target hosts from the subfamily Mirinae. Despite the fact that laboratory tests demonstrated a high parasitism level in non-targets, ecological assessments in both North America and Europe suggest a much lower impact of P. digoneutis on non-target mirids. It was concluded that ecological host range studies in the area of origin provide useful supplementary data for interpreting pre-release laboratory host range testing.
Henneman M.L. and Memmott J. (2001). Infiltration of a Hawaiian community by introduced biological control agents. Science 293: 1314-1316.
Hoelmer K.A., Schuster D.J. and Ciomperlik M.A. (2008).
Indigenous parasitoids of Bemisia in the USA and potential for non-target impacts of exotic parasitoid introductions.
Pp. 307-324 In: Classical biological Control of Bemisia tabaci in the United States - A review of interagency research and implementation, J. Gould, K. A. Hoelmer and J. Goolsby (Ed.) Springer, Dordtrecht
Surveys to document the presence and species composition of native natural enemies were conducted prior to the introduction of non-indigenous agents against sweetpotato whitefly, Bemisia tabaci biotype B, in the USA. The greatest diversity of native parasitoid species attacking B. tabaci was reported in Florida, where there was most diversity of invasive whitefly species established in Florida. Only two or three parasitoid species were responsible for the majority of parasitism of B. tabaci within any given region of the USA. The predominant species attacking B. tabaci prior to the introduction of new Palearctic parasitoid species were Eretmocerus tejanus (in Texas), Eretmocerus eremicus (Arizona and California), Eretmocerus sp. (undescribed, southeast USA), Encarsia pergandiella/Enc. tabacivora (southeastern USA and Texas), and Encarsia luteola (southwestern USA). Surveys up to 2001 (California) and 2003 (Texas), showed that the exotic species that were introduced have remained limited to their intended target.
Hopper K.R. (1995). Potential impacts on threatened and endangered insect species in the United States from introductions of parasitic Hymenoptera for the control of insect pests. Pp. 64-74 In: Biological Control: Benefits and Risks, H.M.T. Hokkanen and J.M. Lynch (Ed.) Cambridge University Press, Cambridge, UK.
Jacas J.A., Urbaneja A. and Viñuela E. (2006).
History and future of introduction of exotic arthropod biological control agents in Spain: A dilemma?
BioControl 51: 1-30.
More success for IBCAs has been achieved with seasonal inoculative releases (50.0% of cases) than for classical biological control programs (17.1% of cases). Concerns about potential non-target effects but post-release evaluation has often been insufficient to draw any conclusions about them. Most of the biological control agents introduced in Spain were parasitoids (n = 53), and the remainder predators (n = 12). Only four parasitoids are considered monophagous. Using information from literature and the internet, the mean number of host species parasitized by parasitoids is 15.2, Therefore, polyphagy appears to be quite common among the IBCAs that have been introduced in Spain.
Kaufman L.V. and Wright M.G. (2009).
The impact of exotic parasitoids on populations of a native Hawaiian moth assessed using life table studies.
Oecologia 159: 295-304
This study investigated the impact of introduced Hymenoptera parasitoids on the Hawaiian moth Udea stellata (Butler) which has seven alien parasitoids associated with it. The study determined the relative contribution of the seven parasitoid species to the population dynamics of U. stellata. The factors found to contributed to total mortality were: disappearance (42.1%), death due to unknown reasons during rearing (16.5%) and parasitism (4.9%). Adventive parasitoids inflicted greater total larval mortality attributable to parasitism (97.0%) than purposely introduced species (3.0%).
Kuris A.M. (2003).
Did biological control cause extinction of the coconut moth, Levuana iridescens, in Fiji?
Biological Invasions 5: 133-141.
Biological control of Levuana iridescens, the endemic coconut moth of Fiji, was so successful that this pest of the copra crop had been reduced to almost undetectable levels by the tachinid fly, Bessa remota. This example is presented in the modern literature as the first and best documented extinction of a species due to biological control and portrayed as an example of the highly controversial practice of neoclassical biological control. However, the moth was likely not to be native to Fiji and might have spread to other island groups in the South Pacific, and may not be extinct. A strategy to search for L. iridescens populations is proposed and development of biological control of B. remota, using hyperparasitoids, is possible.
Kuske S., Babendreier D., Edwards P., Turlings T.C.J. and Bigler F. (2004).
Parasitism of non-target Lepidoptera by mass released Trichogramma brassicae and its implication for the larval parasitoid Lydella thompsoni.
Biocontrol 49: 1-19.
The release of high numbers of the egg parasitoid Trichogramma brassicae Bezd. (Hym. Trichogrammatidae) to control the European corn borer, Ostrinia nubilalis Hb. (Lep.: Crambidae) in maize has raised concerns about potential negative effects on native natural enemies, particularly Lydella thompsoni Herting (Dipt.: Tachinidae) Inundative releases of T. brassicae coincide with the oviposition period of the alternative hosts of the tachinid. T. brassicae upon which it relies in spring. Laboratory host specificity tests showed that the tachinid's two most abundant spring hosts are successfully parasitised by T. brassicae females in no-choice situations. Field surveys, however, showed that the two spring hosts escape parasitism since their eggs are well hidden or not attractive, and the study concluded that negative effects of inundative releases of T. brassicae on the native tachinid fly L. thompsoni, are unlikely.
Mason P.G., Broadbent A.B., Whistlecraft J.W. and Gillespie D.R. (2011). Interpreting the host range of Peristenus digoneutis and Peristenus relictus (Hymenoptera: Braconidae) biological control agents of Lygus spp. (Hemiptera: Miridae) in North America. Biological Control 57: 94-102.
Memmott J. (1999). Food webs as a tool for studying nontarget effects in biological control. Pp. 147-163 In: Nontarget effects of biological control introductions, P.A. Follett and J.J. Duan (Ed.) Kluwer Academic Publishers, Norwell, Massachusetts, USA.
Memmott J., Martinez N.D. and Cohen J.E. (2000).
Predators, parasitoids and pathogens: species richness, trophic generality and body sizes in a natural food web.
Journal of Animal Ecology 69: 1-15.
A food web is presented which describes trophic interactions among the herbivores, parasitoids, predators and pathogens associated with broom, Cytisus scoparius (L.) Link. The web comprises a total of 154 taxa: one plant, 19 herbivores, 66 parasitoids, 60 predators, five omnivores and three pathogens. There are 370 trophic links between these taxa in the web. The taxa form 82 functionally distinct groups, called trophic species. Predators consumed more species than did parasitoids; externally feeding herbivores were most vulnerable and the concealed herbivores were least vulnerable. Miners were vulnerable to the most parasitoid species and externally feeding herbivores were the most vulnerable to predators. Relative sizes of predators and parasitoids are discussed.
Moriya S., Inoue K., Shiga M. and Mabuchi M. (1992).
Interspecific relationship between and introduced parasitoid, Torymus sinensis Kamijo, as a biological control agent of the chestnut gall wasp, Dryocosomus kuriphylus Yasumatsu, and an endemic parasitoid, T. beneficus Yasumatsu et Kamijo.
Acta Phytopathologia et Entomologica Hungarica 27: 479-483.
The interspecific relationship of a parasitoid of Dryocosmus kuriphilus that was endemic to Japan (Torymus beneficus) and an introduced control agent (T. sinensis) was investigated. The ovipositor sheath is longer in T. sinensis than in T. beneficus and 1990 they made up about 90% of the emerging parasitoids. In crossing experiments, females with ovipositor sheaths of intermediate length were observed and F1 females were fertile when backcrossed to males of the parent species. Females with intermediate ovipositors were observed in the field from 1984.
Morrison-Lloyd W. (2006). Post-release host-specificity testing of Pseudacteon tricuspis, a phorid parasitoid of Solenopsis invicta fire ants. BioControl 51: 195-205.
Munro V.M.W. and Henderson I.F. (2002).
Nontarget effect of entomophagous biocontrol: shared parasitism between native lepidopteran parasitoids and the biocontrol agent Trigonospila brevifacies (Diptera: Tachinidae) in forest habitats.
Environmental Entomology 32: 388-396.
The parasitoid guild attacking Tortricidae on broadleaf/podocarp forests was studied at six sites in the central North Island. Host parasitoid interactions at a community level between native parasitoids and the introduced species Trigonospila brevifacies (Hardy) were investigated. T. brevifacies was numerically dominant in the tortricid parasitoid guild and it parasitized more species of Tortricidae than other parasitoids at the North Island forest sites surveyed. Only the introduced Australian canefruit pest Eutorna phaulocosma Meyrick (Lepidoptera: Oecophoridae) received a higher proportion of parasitism from T. brevifacies than any of the native Lepidoptera. All native parasitoid species were less abundant than T. brevifacies.
Nafus D.M. (1993). Movement of introduced biological control agents onto nontarget butterflies, Hypolimnas spp. (Lepidoptera: Nymphalidae). Environmental Entomology 22: 265-272.
Porter S.D., Valles S.M., Davis T.S., Briano J.A., Calcaterra L.A., Oi D.H. and Jenkins A. (2007).
Host specificity of the microsporidian pathogen Vairimorpha invictae at five field sites with infected Solenopsis invicta fire ant colonies in northern Argentina.
Florida Entomologist 90: 447-452
The microsporidian pathogen Vairimorpha invictae was evaluated for release in the United States as a biological control agent for imported fire ants. The host range of this pathogen was examined showing that Solenopsis invicta Buren fire ant colonies had high levels of infection (28-83%) at one site, but none were found in ants at other sites. The results of this study indicate that, in its native South American range, V. invictae is specific to Solenopsis fire ants.
Purcell M.F., Duan J.J. and Messing R.H. (1997). Response of three hymenopteran parasitoids for fruit fly control to a gall-forming tephritid, Procecidochares alani (Diptera: Tephritidae). Biological Control 9: 193-200.
Shiga M. (1999).
Classical biological control of the chestnut gall wasp, Dryocosmus kuriphilus: present status and interactions between an introduced parasitoid, Torymus sinensis, and native parasitoids.
Pp. 175-188 In: Biological invasions of ecosystem by pests and beneficial organisms, E. Yano, K. Matsuo, M. Shiyomi and D.A. Andow (Ed.) National Institute of Agro-Environmental Sciences, Tsukuba, Japan.
This research demonstrates a case of displacement of a native by and introduced parasitoid.
Toepfer S., Cabrera W.G., Eben A., Alvarez-Zagoya R., Haye T., Zhang F. and Kuhlmann, U. (2008).
A critical evaluation of host ranges of parasitoids of the subtribe Diabroticina (Coleoptera: Chrysomelidae: Galerucinae: Luperini) using field and laboratory host records.
Biocontrol Science and Technology 18: 483-504
The subtribe Diabroticina are New World Chrysomelidae including corn rootworms, cucumber beetles and other pests. The only parasitoids that consistently target and develop inside the beetle adults are Centistes gasseni Shaw, Centistes diabroticae Gahan (both Hym.: Braconidae), and Celatoria diabroticae Shimer, Celatoria compressa (Wulp), Celatoria bosqi Blanchard, and Celatoria setosa Coquillett (all Diptera: Tachinidae). The authors present new host records and data from laboratory host range tests showing that all tachinid and braconid species studied are considered to be specific at the level of subtribe. The realized and potential host range of Centistes diabroticae includes Acalymma species as well as species in the fucata and virgifera groups of Diabrotica. Celatoria compressa has the broadest realised range compared to the other species studied, since it was obtained from species in several genera of Diabroticina; and its potential host range may also include Old World Aulacophora species.
Wyckhuys K.A.G., Koch R.L., Kula R.R. and Heimpel G.E. (2009).
Potential exposure of a classical biological control agent of the soybean aphid, Aphis glycines, on non-target aphids in North America.
Biological Invasions 11: 857-871
In 2007, the Asian parasitoid Binodoxys communis (Hymenoptera: Braconidae) was released in North America for control of the exotic soybean aphid, Aphis glycines (Hemiptera: Aphididae). To estimate the risk of exposure of non-target aphids to B. communis, the authors merged assessments of temporal co-occurrence with projections of spatial overlap between B. communis and three native aphid species. The degree of temporal overlap depended greatly on location and the non-target aphid species. Geographic overlap between B. communis and native aphids based upon Climex modeling was used to assess the degree of geographic overlap between the parasitoid and non-target species. The authors were able to make broad statements regarding the ecological safety of current B. communis releases and their potential impact on native aphid species in North America.
Yara K., Sasawaki T. and Kunimi Y. (2010). Hybridization between introduced Torymus sinensis (Hymenoptera: Torymidae) and indigenous T. beneficus (late-spring strain), parasitoids of the Asian chestnut gall wasp Dryocosmus kuriphilus (Hymenoptera: Cynipidae). Biological Control 54: 14-18
Zimmermann G. (2007).
Review on safety of the entomopathogenic fungus Metarhizium anisopliae.
Biocontrol Science & Technology 17: 879-920
Metarhizium anisopliae (Metschn.) Sorokin is widely used for biocontrol of pest insects, and many commercial products are on the market or under development. This review summarises all relevant safety data for this fungus, which are necessary for the commercialisation and registration process. On the basis of the presented knowledge, M. anisopliae is considered to be safe with minimal risks to vertebrates, humans and the environment.
Weed biological control agents