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Beneficial arthropods are often used for suppressing specific pest outbreaks in agricultural crop systems. The European earwig, Forficula auricularia L., (Dermaptera: Forficulidae), is an important natural enemy in fruit orchards. Recently, ecological studies were published describing earwig dispersal and survival during summer, hereby revealing clear differences between populations with a single brood (SBP) and two broods a year (DBP). In this article, we will describe three potential mortality factors of earwigs during the underground winter period, namely cold temperatures, parasitoids and soil tillage. This knowledge is essential for making efficient management strategies for increasing earwig abundance in fruit orchards. The effect of cold temperatures was checked during a 3-year semi-field experiment. Parasitism rates of Triarthria spp. (Fallen) and Ocytata pallipes (Fallen) (Diptera: Tachinidae) were obtained in a rearing experiment. The negative effect of soil tillage on the survival of earwigs nests was checked in a field experiment covering a 4-year time period. A strong, negative relation between temperature [cooling day degrees (CDD)] and survival of female and male earwigs during winter was found. Male earwigs of SBP died very quickly, mimicking natural conditions. Between 60% and 90% of females do not survive winter. Survival of females in DBP was higher than in SBP. Parasitism rates vary a lot between species, generation, year and location (0–20%). During winter, we found a maximum mortality of 13%. There is a clear trend that soil tillage can reduce the number of nymphs in spring and summer by 50%. Implications for biocontrol are the following: (i) mortality owing to temperature can be predicted using CDD and if necessary preventive management actions can be undertaken to control pests; (ii) parasitism rates are negligible compared to high impact of temperature; and (iii) soil tillage can be timed more accurately using a recently developed day degree model.

Understanding the role of unmanaged arthropod flower visitors as crop pollinators is critical if robust and reliable long-term alternatives are to be found for honey bee pollination. However, data on pollinator assemblages can be scant. Field observation of crop flower visitors is a common data collection technique but it can be inadequate for species identification and is labour-intensive if used across many sites. Trapping may reduce this problem, but trap performance and sampling consistency over long distances (sites separated by >100 km) are rarely examined. Window traps were designed to collect flower-visiting arthropods from peak-flowering onion (Allium cepa) and pak choi (Brassica rapa var. chinensis) fields across several regions throughout New Zealand. Trap efficacy was evaluated by comparing trapped samples with observations of flower visiting arthropods during the same trapping period, from dawn (6:00 to 7:00 hours) through to dusk (20:00-21:00 hours) at the same locations. Similar types of larger arthropods (length greater-than-or-equal3 mm) were observed and trapped within both crops, with the hymenopteran genera Apidae, Colletidae and Halictidae and the dipteran families Syrphidae, Calliphoridae, Anthomyiidae, Stratiomyidae, Sarcophagidae, Bibionidae, Tachinidae and Muscidae the most commonly recorded. The total counts of these taxa across fields were strongly correlated between the two methods; however, the ratio of trapped to observed individuals could vary greatly between taxa. Trapping allowed more arthropods to be identified to the species level and also helped record more small arthropods (body length

Gonometa postica Walker produces silk of high quality, but it is affected by parasitoids attack. A study on the parasitism of G. postica larvae and pupae on host and non-host plants were undertaken for the first and second generations, corresponding to the long (March–May) and short (October–December) rainy seasons in 2006 at six field sites, three each in the Imba and Mumoni forests of Mwingi, eastern Kenya. All freshly spun cocoons of G. postica were sampled at each site from a total of 100 trees of host plants and other non-host plants where they have migrated before pupation. The cocoons were kept individually in fine net-sealed plastic vials to determine percentage parasitism. Two dipterans and four hymenopteran larval–pupal parasitoids were identified from the two forests. The most common parasitoids were Palexorista sp. (Diptera: Tachinidae) and Goryphus sp. (Hymenoptera: Ichneumonidae) with parasitism ranging from 1.8 to 32.7% and 2.2 to 7.5%, respectively. Parasitism varied significantly according to host or non-host plants, seasons and sites. This study indicates that, of the six parasitoid species recovered, only two had a significant impact in reducing the quality of the cocoons.

Biological control is a relatively benign method of pest control. However, considerable debate exists over whether multiple natural enemies often interact to produce additive or non-additive effects on their prey or host populations. Based on the large data set stored in the Sao Joao and Barra sugarcane mills (state of Sao Paulo, Brazil) regarding the programme of biological control of Diatraea saccharalis using the parasitoids Cotesia flavipes and tachinid flies, in the present study the author investigated whether the parasitoids released into sugarcane fields interfered significantly with the rate of parasitized D. saccharalis hosts. The author also observed whether there was an additive effect of releasing C. flavipes and tachinids on the rate of parasitized hosts, and looked for evidence of possible negative effects of the use of multiple parasitoid species in this biological control programme. Results showed that C. flavipes and the tachinids were concomitantly released in the Barra Mill, but not in the Sao Jao Mill. Furthermore, in the Barra Mill there was evidence that the parasitoids interacted because the percentage of parasitism did not increase after the release of either C. flavipes or tachinids. In the Sao Joao Mill, when both parasitoid species were released out of synchrony, both the percentage of parasitism by C. flavipes as well as that of the tachinids increased. When large numbers of tachinids were released in the Barra Mill, they caused a significant lower percentage of parasitism imposed by C. flavipes. The implications of the results as evidence of non-additive effects of C. flavipes plus tachinids on D. saccharalis populations are discussed.

Parasitism and pathogen mortality of Lymantria dispar were compared between host populations of different densities in Slovakia and Austria. Over a period of 4 years, L. dispar eggs, larvae, and pupae were collected in a stage-specific manner at three mixed oak stands in each country and reared in the laboratory to assess parasitoid and pathogen mortality. At sites with low host densities, L. dispar abundance was artificially augmented by exposing egg masses and young larvae. We ascertained marked differences between the natural enemy complexes of L. dispar populations in Slovakia and Austria. Overall, pathogens caused highest mortality in the former and parasitoids in the latter. Moreover, the species composition differed significantly between both countries. High variation was also observed between years and host populations at different densities. The investigations revealed that egg parasitization was low in Slovak L. dispar populations, and no egg parasitoids were found in Austria. Larval and pupal parasitism was low at sites with outbreak populations, but higher at the Austrian than at the Slovak site. The tachinid Parasetigena silvestris was the dominant species at elevated host densities. Nuclear polyhedrosis virus also caused significant mortality in these cases. An increase in parasitism by several species was noticed after the breakdown of L. dispar populations. The ichneumonid Phobocampe spp. caused high levels of parasitism during the post-culmination years. At sites where host abundance increased in the first year of the study, significant differences between the Austrian and the Slovak locality could be ascertained. Mortality was low in the population at the latter site, and host abundance increased to outbreak levels the year after. The population at the Austrian site suffered high parasitism by the tachinids P. silvestris and Blepharipa pratensis and this might have contributed to the prevention of a further increase in L. dispar abundance in this locality. Braconids showed a strong reaction to the local, artificial increase in host density at study plots with innocuous L. dispar populations. Particularly high parasitism by Glyptapanteles liparidis was observed at the Austrian site, but G. porthetriae and Cotesia melanoscela also accounted for significant mortality in both low-density populations. The artificial L. dispar populations were usually eradicated by natural enemies before pupation of the hosts.

Species composition and impact of larval parasitoids during an endemic density phase of a pine forest pest, the common pine sawfly Diprion pini (L.), were investigated by exposure of laboratory-reared larvae of the sawfly to parasitoid attack in natural habitats. Colony-associated host larvae of different instars were exposed continuously from early June until end of September of the years 1994 and 1995 in two pine stands with a different history of pine sawfly outbreaks. Host larvae were exchanged after a defined time interval and those collected up were examined in the laboratory for parasitism. Parasitoid assemblages were shown to be very species poor at both pine stands. The dominant species were the ichneumonid Olesicampe macellator and the tachinid Drino gilva, which reached attack rates on the collected host larvae of 60 and 94%, respectively, during peak activity. The patterns of temporal attack, of multiparasitism, and of superparasitism of these dominant species were studied. In an additional experiment, the response of these species to different host-patch sizes (number of host larvae per colony) were investigated. No aggregative response to higher host-patch densities could be detected. The role and function of these larval parasitoids in the population dynamics of D. pini are discussed.

Biological control of the silkworm pest (Exorista bombycis) was partly successful by using a new hymemopteran biocontrol agent Trichopria khandalus, recovered from the environs of a cocoon market in Hindupur district of Andhra Pradesh (India). T. khandalus is a tiny (1–1.5 mm) endoparasite, the females were found to parasitize the uzifly puparia. The progeny developed inside the uzi pupa, and the adults (140–160 individuals from a single pupa) emerged after about 18–25 days depending on the seasonal extrinsic factors. The lift cycle of T. khandalus averaged 32 days. Due to the favourable sex ratio (2:3 male/female) and high preference to parasitize uzi puparia it is qualified as a good biocontrol agent for the control of E. bombycis. Prospects for utilizing this hyperparasite to manage and eliminate the uzi populations are discussed in the light of its data on biology, and easily manageable mass multiplication in the insectary.

The uzifly, Exorista bombycis, is an endoparasite of the silkworm which causes severe damage to silkworm resulting to economic loss to the silk industry in India. All control methods to bring down the uzi menace have been unsuccessful, hence novel approaches like biological control methods and the use of pheromones and kairomones have been tried. The odoriferous compounds, broadly termed as kairomones, were extracted from the dipteran pest of the silkworms, i.e. the uzifly (Exorista bombycis) pupae. Different solvents like chloroform, methanol, acetone, hexane and dichloromethane were used in order to determine the extractability of the compounds of our interest. As a result of the bioassay experiments against the target insect, i.e. Trichopria khandalus, it was found that the methanol and acetone extracts contained the useful compounds. Results showed that the kairomone blend consisted of organic acids like acetic acid, isobutyric acid, 1-methyl-butanoic acid alcohols and other compounds. To our knowledge this is the first report on extraction and use of kairomones to attract the hyperparasite to its host and its possible utilization to determine the prevalence of the hyperparasite in sericultural pockets by an environmentally friendly method.

This paper presents data on the life history and an analysis of field parasitism, in central Europe, of Ocytata pallipes (Fallen), a tachinid that parasitizes the European earwig, Forficula auricularia. O. pallipes is a species with microtype eggs that are deposited on earwig food plants with feeding marks of the host. In order to develop, the eggs have to be eaten by the host. The larvae hatch in the intestinal tract from where they penetrate the haemocoel. A high reproductive potential with an average of 1040 eggs has been observed. In all areas of Europe, the parasitoid is partially bivoltine. In northern Germany, the adults of the first generation emerge between the end of June to mid July; the second generation emerges from September to the end of October. The winter is passed as second instar larvae in the living host. Reared earwigs collected in a number of regions show parasitization of less than 1 %. This species is more common in maritime areas. Zusammenfassung Zur Biologie und Parasitierungsleistung von Ocytata pallipes (Fallen) (Dipt., Tachinidae), ein Parasitoid des Gemeinen Ohrwurms In dieser Arbeit wird die Biologie und der Parasitierungserfolg von der Tachinide Ocytata pallipes, ein Parasitoid des Gemeinen Ohrwurms (Forficula auricularia) in Europa beschrieben. Ocytata pallipes legt die sehr kleinen, microtypen Eier, die bereits eine fertig entwickelte Erstlarve enthalten, auf die Futterpflanze von F. auricularia ab. Der Ohrwurm nimmt das Ei zusammen mit der Nahrung auf, die Erstlarve schlupft im Vorderdarm und dringt in die Leibeshohle ein. Die potentielle Natalitat der Weibchen betragt im Durchschnitt 1040 Eier. Der Parasitoid ist in allen untersuchten Regionen Europas partiell bivoltin. In Norddeutschland schlupfen die Tachinen der 1. Generation von Ende Juni bis Mitte Juli, und die der 2. Generation von September bis Mitte Oktober. Das 2. Larvenstadium von O. pallipes uberwintert im Wirt. Der Parasitierungserfolg war in allen Regionen Europas sehr gering, nur in den Kustengebieten Norddeutschlands trat der Parasitoid haufiger auf.

Phyllophaga anxia (LeConte), is the most common and destructive species of June beetle in the province of Quebec, Canada. In the course of a systematic 4-year survey in southern Quebec, 29 species (belonging to 13 families in 3 orders) of parasitic and predaceous insects were found associated with the pest. Tachinid flies and tiphiid wasps were the most common parasites. The roles of the parasites and predators of P. anxia are reviewed. The survey showed that these natural enemies had low impact on field populations of the June beetle. Zusammenfassung Parasitoide und rauberische Insekten als Feinde von Phyllophaga anxia (LeConte) (Col., Scarabaeidae) in Quebec, Kanada Phyllophaga anxia ist der haufigste und gefahrlichste Schadling unter den Junikafern in der kanadi-schen Provinz Quebec. Im Verlauf einer 4jahrigen Untersuchung im sudlichen Quebec wurden 29 Arten (aus 13 Familien und 3 Ordnungen) parasitoider und rauberischer Insekten gefunden, die mit dem Schadling assoziiert waren. Davon waren die Tachiniden und Tiphiiden die haufigsten Parasitoiden. Die Rolle der Parasitoiden und Pradatoren bei P. anxia wird zusammenfassend dargestellt. Die Ubersicht zeigt, das diese naturlichen Feinde bei der Regulation der Junikafer-Population nur eine geringe Rolle spielen.

The dispersion patterns of the larval planidia of Ormia depleta was studied in circular arenas. After placing 25 larvae in the center of the arena, their angle of distribution and distance travelled was recorded 15 min later. No innate directional orientations were evidenced, nor was evidence found for either positive or negative orientation to point sound and light sources. In all cases, dispersion was bimodal, with most dispersing only 1 cm, and a much smaller peak found at 10 cm. The bimodality of dispersal distances may be a response to the sexual behavior of its host, mole crickets of the genus Scapteriscus. Zusammenfassung Zur Larvenausbreitung beim Parasitoiden Ormia depleta (Towns.) (Dipt., Tachinidae) Das Ausbreitungsmuster der Larven der Maulwurfsgrillen-Tachine Ormia depleta wurde im Labor auf runden (mit feuchtem Filterpapier bedeckten) Flachen untersucht. Nach Placierung von je 25 Larven im Zentrum der Arena wurden 15 Min. spater der Ausbreitungswmkel und die zuruckgelegte Entfernung registriert. Es wurden weder eine endogene Richtungsorientierung, noch eine positive oder negative Orientierung gegenuber Ton- und Lichtquellen festgestellt. In allen Fallen war die Ausbreitung bimodal mit einem absoluten Ausbreitungsmaximum von nur 1 cm; ein viel geringeres Maximum lag bei 10 cm. Die Bimodalitat der Ausbreitung konnte eine Antwort auf das Sexualverhalten des Wirtes, einer Maulwurfsgrille der Gattung Scapteriscus, sein.

Comparisons are made between different methods of sampling gypsy moths (Lymantria dispar L.) (Lep., Lymantriidae) to evaluate parasitism. Parasitism rates from collections of specific developmental stages were compared with parasitism of weekly collections from foliage, branch- and bole-bands. Data were grouped according to developmental stage or collection date and expressed as average seasonal, peak or aggregate parasitism. Sampling to estimate parasitism by Compsilura concinnata (Meigen) (Dipt., Tachinidae) could be confined to Julian dates 161–182. To estimate field parasitism, we recommend weekly sampling, systematically over an entire study site, regardless of immature developmental stage. Zusammenfassung Untersuchungen zur Erfassung der Parasitoiden einer in Vermehrung begriffenen Schwammspinner-Population (Lymantria dispar L., Lep., Lymantriidae) Es wurden vergleichende Untersuchungen durchgefuhrt uber verschiedene Methoden der Parasitoiden-Erfassung beim Schwammspinner, Lymantria dispar. Dabei wurden die Parasitierungsquoten bestimmter Entwicklungsstadien miteinander und mit den Quoten aus wochentlichen Raupenauf-sammlungen an Blattern, Zweigen und Stammen verglichen. Die Daten wurden nach Entwicklungs-stadium oder Sammlungsdatum gruppiert und als mittlerer, maximaler oder aggressiver Parasitismus deklariert. Das Sammeln zur Einschatzung des Parasitismus durch Compsilura concinnata (Meig.) lies sich auf die julianischen Daten 161–182 begrenzen. Zur Erfassung des Freiland-Parasitismus bei L. dispar wird ein wochentliches Sammeln an einem bestimmten Ort, unabhangig von den Entwick-lungsstadien, empfohlen.

Field and laboratory studies on the parasitoids of Pieris rapae (L.) in winter cabbage season of 1989/90 at Mansoura district were carried out. No parasitoids were emerged from the larvae of the host. Pteromalus puparum (L.), Brachymeria femorata Panz. and Exorista larvarum (L.) (Tachina larvarum) were only emerged from the pupae of the host. General rate of parasitism induced by the three parasitoids together reached 49.69%. The most common parasitoid was P. puparum followed by B. femorata, while E. larvarum considered to be of little importance. The total developmental period of P. puparum lasted 32.57 ± 0.84 and 11.2 ± 0.29 days at 18.6°C and 27°C, respectively. The highest number of adult P. puparum that emerged from a single parasitized host pupa was obtained at 27°C, with the lowest sex ratio of 2.5 females per male. Its lowest number was recorded at 18.6°C, with the highest sex ratio of 7.5 females per male. Survival rate of the adult females of this parasitoid refrigerated at 10°C exceeded 84 % after 14 days and sharply decreased to 4% and 0% after 21 and 28 days, respectively. Zusammenfassung Okologische und biologische Untersuchungen zur Parasitoidenfauna von Pieris rapae (L.) (Lep., Pieridae) an Winterkohl in Mansoura 1989/90 wurden im Distrikt Mansoura Freiland- und Laborversuche zur Parasitoidenfauna von Pieris rapae durchgefuhrt. Aus den Wirtslarven schlupften keine Parasitoide. Ptermalus puparum (L.), Brachymeria femorata Panz. und Exorista larvarum (L.) (Tachina larvarum) schlupften nur aus den Puppen des Wirts. Die Gesamtparasitierungsrate erreichte 49,69%. Der haufigste Parasitoid war P. puparum, gefolgt von B. femorata, wahrend E. larvarum offensichtlich nur eine geringe Bedeutung hatte. Die Gesamtentwicklungsdauer betrug bei P. puparum 32,57 ± 0,84 Tage bei 18,6°C bzw. 11,2 ± 0,29 Tage bei 27°C. Bei einer Temperatur von 27°C schlupften pro Wirtspuppe die meisten P. puparum-Adulten mit dem niedrigsten Geschlechterverhaltnis von 2,5 ♀ ♀: 1 ♂. Die geringste Parasitoidenzahl schlupfte bei 18,6°C; bei dieser Temperatur lag das Geschlechterverhaltnis mit 7,5 ♀ ♀: 1 ♂ am hochsten. Adulte P. puparum-Weibchen uberlebten zu 84% eine 14tagige Kuhlung auf 10°C; nach 21 bzw. 28 Tagen bei 10°C betrug die Uberlebensrate nur noch 4 bzw. 0%.

The effects of strip-cropping haricot bean (Phaseolus vulgaris L.) with maize (Zea mays L.) under weedy and weed-free conditions on the abundance of tachinid parasitoids and a predatory wasp (Tiphia sp. ?sjostedti Cameron) that are associated with African bollworm [Heliothis armigera (Hbn.)] were studied at Awassa, southern Ethiopia, during the 1987 and 1988 crop seasons. Tachinids were more abundant in strip-cropped and weedy plots than in bean monoculture. Strip-cropping had no effect on Tiphia numbers whereas the wasp was 2- to 8-times more abundant in weedy than in weed-free plots. In general, tachinid and Tiphia numbers increased with increasing habitat diversity. Zusammenfassung Zum Einflus von Mischkulturen und Unkrautern auf einige naturliche Feinde von Heliothis armigera Hbn. (Lep., Noctuidae) in Bohnenfeldern In Awassa, Sudathiopien, wurde in den Vegetationsperioden 1987 und 1988 untersucht, welchen Einflus die reihenweise Einbringung von Mais (Zea mays L.) in Bohnenfelder (Phaseolus vulgaris L.) auf die Adundanz von Parasitoiden und Pradatoren von Heliothis armigera hat. Die Untersuchungen wurden in unkrautfreien Feldern und in solchen mit Unkrautwuchs durchgefuhrt. Parasitoide (Tachinen) waren haufiger in Mischkulturen mit Unkrautwuchs festzustellen als in Monokulturen. Die reihenweise Einbringung von Mais hatte keinen Einflus auf die Populationsdichte von Tiphia sp. sjostedti Cameron, dagegen konnte diese rauberische Hymenoptere 2- bis 8mal haufiger in Feldern mit Unkraut als in unkrautfreien Feldern festgestellt werden. Insgesamt konnte beobachtet werden, das die Tachinen- und Tiphia-Anzahl mit zunehmender Diversitat des Habitats zunahm.

Surveys conducted in the Mediterranean parts of Europe, North Africa, and of the Middle East have revealed that M. exigua had, in fact, a much wider distribution range than previously recorded. Eight common species of the genus Sitona are reported here as hosts of the tachinid, which was by far the predominant natural enemy of adult weevils in the Provence (southern France, 61.2% of the entomophagous complex), and in Greece (54.9%). The importance of M. exigua was exceptionally high in southwest Anatolia (Asian Turkey, 94.6 % of the complex of natural enemies), where the fly apparently played a key role in the regulation of the population dynamics of Sitona spp., reaching a parasitization rate of 57.1 % on average for the period 1981–84. Zusammenfassung Zur Verteilung und Bedeutung von Microsoma exigua Mg. (Dipt., Tachinidae) als Parasitoid von imaginalen Sitona-Kafern (Col., Curculionidae) im Mittelmeergebiet Langjahrige Untersuchungen im sudlichen Europa, in Nordafrika und im Nahen Osten haben gezeigt, das M. exigua in dieser Region eine viel weitere Verbreitung hat, als bisher angenommen. Als Wirte der Tachinenart konnen 8 haufige Arten der Gattung Sitona dienen. M. exigua war der weitaus wichtigste naturliche Feind von Sitona-Kafern in der Provence (Sudfrankreich), wo sie 61.2% der Totalparatisierung verursachte, in Griechenland 54.9%, und im sudwestlichen Anatolien (Turkei) 94.6 %. In der letztgenannten Gegend war die Bedeutung der Tachinenfliege auserordentlich hoch, da in den Jahren 1981–1984 durchschnittlich 57.1 % der Sitona-Populationen von M. exigua befallen wurden.

Various stages of Thaumetopoea wilkinsoni Tams were found to be affected by 7 parasitoids, 21 predators and 6 entomopathogenic organisms, the most common being Ooencyrtus pityocampae (Merc.) (Hym., Encyrtidae), Eutetrastichus servadeii Dom. (Hym., Eulophidae) and Beauveria hassiana Vuill. (Fungi imperfecti). The numbers of species parasitizing T. solitaria (Frr.) and T. jordana (Stgr.) are five and three, respectively. Some details of research are reported on O. pityocampae, E. servadeii, Exorista segregata Rond (Dipt., Tachinidae) and B. hassiana. Zusammenfassung Die naturlichen Feinde von Thaumetopoea spp. (Lep., Thaumetopoeidae) in Israel Als naturliche Feinde der verschiedenen Entwicklungsstadien von Thaumetopoea wilkinsoni Tams wurden 7 Parasitoide, 21 Pradatoren und 6 entomopathogene Organismen registriert. Die haufigsten waren Ooencyrtus pityocampae (Merc.) (Hym., Encyrtidae), Eutetrastichus servadeii Dom. (Hym., Eulophidae) und Beauveria bassiana Vuill. (Fungi imperfecti). Von T. solitaria und T. jordana konnten nur 5 bzw. 3 Arten von Parasitoiden festgestellt werden. Nahere Befunde werden zu O. pityocampae, E. servadeii, Exorista segregata Rond. (Dipt., Tachinidae) und B. bassiana mitgeteilt.

The action of the fenoxycarb (an IGR JH mimetic) on the development of the tachinid parasitoid P. nigrolineata was tested by application onto its host O. nubilalis (by dipping larvae into acetone solution at 0 to 5 μg/μl). The duration of the larval development of the parasitoid (from host 4/5 ecdysis to pupariation) increased with the fenoxycarb concentrations from 11 days for control to 19 for 5 μg. The duration of the puparial stage was only slightly affected. Fenoxycarb treatment induced a high mortality of parasitoid instars II and III: 37% with 5 μg vs. 0 with control. The yield in flies was reduced from 49% for controls to 31% for 5 μg. The larval growth was strongly delayed by the IGR: about 50% of “treated” parasitoids were still in instar I, 6 d after 4/5 host ecdysis vs. 5% in controls. Fenoxycarb “treated” larvae stopped their growth especially in instar II, at a weight near 1 mg, such that 50% were still in this state 22 d after 4/5 ecdysis while 92% of control larvae had become pupariae. Contrary to some questionable results previously reported on the benign action of fenoxycarb on different beneficial insects, this IGR appeared harmful for the tachinid larvae tested. This JH mimetic, broadly used especially on orchard pests should be more carefully sprayed with consideration for the natural enemies. Resume Perturbations du developpement du parasitoide Pseudoperichaeta nigrolineata (Dipt., Tachinidae) par le fenoxycarbe, un Regulateur de Croissance d'Insecte, applique sur son hote Ostrinia nubilalis (Lep., Pyralidae) L'action du fenoxycarbe (un RCI mimetique de l'H.J.), sur le developpement du Tachinide parasitoide P. nigrolineata a ete testee par application sur son hote O. nubilalis (trempage des chenilles dans des solutions acetoniques contenant de 0 a 5 μg/μl de fenoxycarbe). La duree du developpement larvaire du parasitoide (de la mue 4/5 de l'hote a la pupaison) augmente avec la concentration en fenoxycarbe: 11 jours pour les temoins et 19j. avec 5 μg. La duree du developpement intrapupaire est legerement reduite avec la concentration maximale. Le traitement au fenoxycarbe induit une forte mortalite des stades larvaires II et III de P. nigrolineata: 37% avec 5 μg contre 0 avec les temoins. Le rendement en mouches par hote est reduit de 49% pour les temoins a 31% avec 5 μg. La croissance larvaire est fortement retardee par le RCI: pres de 50% des parasitoides « traites » sont encore au stade I, 6 j. apres la mue 4/5 de l'hote, contre 5% chez les temoins. C'est en particulier au stade II, a un poids proche de 1 mg, que les larves traitees arretent leur croissance: ainsi a 22 j. apres la mue 4/5, 50% d'entre elles sont encore dans cet etat alors que 92% des temoins sont deja des pupes. Contrairement a certains resultats, souvent discutables, precedemment relates par les auteurs sur l'action du fenoxycarbe sur differents insectes auxiliaires, ce RCI s'est revele nocif pour les larves de Tachinaires testees. Le fenoxycarbe est maintenant assez largement utilise pour controler plusieurs insectes indesirables, notamment en vergers, mais il conviendrait de le repandre avec plus d'Attention en tenant compte de la faune utile. Zusammenfassung Entwicklungsveranderungen des Parasitoiden Pseudoperichaeta nigrolineata (Dipt., Tachinidae) durch Behandlung seines Wirtes, Ostrinia nubilalis (Lep., Pyralidae) mit dem Insektenwachstumsregulator Fenoxycarb Die Einwirkung von Fenoxycarb auf die Tachinenlarve wurde durch Tauchen der Raupe von O. nubilalis in eine Acetonlosung (0 bis 5 μg/μl) des Wachstumhemmstoffes getestet. Die Dauer der Larvenentwicklung des Parasitoiden (von der 4/5 Wirtshautung bis zur Verpuppung) nahm mit der Fenoxycarb-Konzentration von 11 Tagen (Kontrolle) auf 19 Tage (5 μg) zu. Dagegen wurde die Dauer des Puppenstadiums nur leicht beeinflust. Die Fenoxycarb-Behandlung bewirkte eine hohe Mortalitat der Parasitoiden-Larvenstadien 2 und 3, und zwar um 37% gegenuber Kontrolle. Die Schlupfquote der Fliegen aus den Puparien verringerte sich von 49% (Kontrolle) auf 31% (5 μg). Das Larvenwachstum wurde durch Fenoxycarb stark verzogert: etwa 50% der, behandelten” Parasitoide befanden sich nach 6 Tagen, (nach der 4/5 Wirtshautung) noch im Larvenstadium 1 gegenuber nur 5% in Kontrolle. Mit Fenoxycarb, behandelte” Larven stoppten ihr Wachstum speziell im Stadium 2 bei einem Gewicht um 1 mg. Etwa 50% befanden sich 22 Tage nach der Behandlung (nach der 4/5 Wirtshautung) noch in diesem Stadium, wahrend 92% der Kontroll-Larven zu Puppen geworden waren. Im Gegensatz zu einigen fraglichen Ergebnissen, denen zufolge Fenoxycarb bei verschiedenen nutzlichen Insektenarten gunstige Wirkungen hervorgerufen hatte, wirkte sich dieser Wachstumshemmer bei der von uns untersuchten Tachinide ungunstig aus. Es sollte daher mit diesem Wirkstoff, der zur Zeit gegen Obstschadlinge breite Anwendung findet, im Hinblick auf die naturlichen Feinde vorsichtiger umgegangen werden.

Contribution to the biology of primary and secundary parasitoids of Lymantria dispar L. (Lep., Lymantriidae) During an outbreak of the gypsy moth Lymantria dispar L. (Lep., Lymatriidae) near Offenburg, South-west Germany, in 1984 until 1986, the biology and effectivness of several primary and secondary parasitoids were investigated in the postculmination phase 1986. Adults of Parasetigena silvestris R.-D. (Dipt., Tachinidae) were most abundant during the larval period of L. dispar. They attached macrotype eggs on second instar and older larvae. In spite of the fact that 50% of these eggs were lost by molting, parasitism raised up to 97%, superparasitism up to 83%. Last instar larvae were parasitized by an average number of 3 maggots, but only one of them developed. They killed their host immediately before pupation. Adults of Blepharipa schineri Mesnil (Dipt., Tachinidae) were also abundant during the larval period of L. dispar. They preferred leave edges damaged by feeding for deposition of microtype eggs. Third instar and older larvae were parasitized. The parasitism raised up to 96%, superparasitism up to 77%. Last instar larvae were attacked by an average number of more than three maggots. They penetrated ganglions of the nervous system but didn't develop before pupation of the host. Only one maggot per host developed. Compared with P. silvestris and B. schineri, Blepharipa pratensis Meigen (Dipt., Tachinidae), Compsilura concinnata Meigen (Dipt., Tachinidae) and Ceranthia samarensis Villeneuve (Dipt., Tachinidae) were rare. They parasitized fourth and higher instar larvae. Low rates of parasitism occured also by Apanteles melanoscelus Ratzeburg (Hym., Braconidae), Apanteles liparidis Bouche, Apanteles porthetriae Muesebeck and Phobocampe disparis Viereck (Hym., Ichneumonidae) in first till fourth instar larvae. Multiparasitism by P. silvestris and B. schineri, raised up to 92%. Keen competition occured between all species. Species with higher velocity of developement succeded: All Hymenoptera asserted successfully against Tachinidae. Within the Tachinidae C. concinnata and C. samarensis were very successful against P. silvestris, which was also very effective against B. schineri. Planidium larvae of Perilampus spec. penetrated muscular fibres of L. dispar larvae but didn't damage their hosts. Later in the season they attacked primary parasites. A. melanoscelus and A. liparidis were parasitized by Perilampus spec. (Hym., Perilampidae), P. silvestris and B. schineri by Perilampus ruficornis Fabricius. The parasitoids effected the collaps of the gypsy moth population in 1986. Zusammenfassung Wahrend einer von 1984 bis 1986 dauernden Massenvermehrung von L. dispar (Lep., Lymantriidae) im Stadtwald von Offenburg wurden in der Retrogradationsphase 1986 Untersuchungen zur Biologie und Wirksamkeit primarer und sekundarer Parasitoide durchgefuhrt. Sehr zahlreich schwarmten Imagines von Parasetigena silvestris Robineau-Desvoidy (Dipt., Tachinidae). Sie belegten L. dispar-Raupen vom zweiten Larvenstadium an aufwarts mit macrotypen Eiern. Trotz hohem Eierverlust durch Hautungen (ca. 50%) erreichte die Invasionsrate der Wirte 97%, maximal 83% waren superparasitiert. Raupen im letzten Larvenstadium waren durchschnittlich von 3 P. silvestris-Larven befallen, von denen sich meist nur eine vollstandig entwickelte. Der Wirt wurde kurz vor der Verpuppung getotet. Weniger haufig waren Imagines von Blepharipa schineri Mesnil (Dipt. Tachinidae) zu finden. Die Weibchen legen ihre Eier vorzugsweise an angefressene Blattrander. Ab Anfang Juni waren Larven im Wirt nachweisbar. Die Invasionsrate der Wirte erreichte 96%, die Superparasitierung betrug maximal 77%. Verpuppungsreife Raupen waren durchschnittlich von mehr als drei Larven befallen. Im Wirt bohrten sich die Parasitenlarven in die Ganglien des Strickleiternervensystems ein, wuchsen aber erst nach der Verpuppung des Wirtes weiter. Je Wirt entwickelte sich nur eine Larve. Weitaus seltener waren Blepharipa pratensis Meigen, Compsilura concinnata Meigen und Ceranthia samarensis Villeneuve (alle Dipt., Tachinidae). Sie parasitierten Raupen des vierten bis sechsten Larvenstadiums. Bei allen Arten blieb die Invasionsrate unter 6%. Apanteles melanoscelus Ratzeburg, Apanteles liparidis Bouche, Apanteles porthetriae Muesebeck (Hym., Braconidae) und Phobocampe disparis Viereck (Hym., Ichneumonidae) parasitierten in geringem Mase Jungraupen des ersten bis vierten Larvenstadiums. Am wirksamsten war P. disparis mit einer Invasionsrate von max. 6%. Bis 92% der Raupen wurden von P. silvestris und B. schineri multiparasitiert. Bei diesen und anderen Fallen interspezifischer Konkurrenz setzten sich die Arten mit schnellerer Entwicklung durch: Alle Hymenopteren waren Tachiniden konkurrenzuberlegen. Innerhalb der Tachinidae setzte sich C. samarensis und C. concinnata gegen P. silvestris durch, die wiederum in hohem Mase B. schineri konkurrenzuberlegen war. Planidiumlarven von Perilampus spec. (Hym., Perilampidae) befielen L. dispar und lebten zuerst in Muskelfasern der Raupen, ohne jedoch den Wirt zu schadigen, spater bohrten sie sich in primare Parasitoide ein. A. melanoscelus und A. liparidis wurden von Perilampus spec., P. silvestris und Blepharipa spec. durch P. ruficornis Fabricius hyperparasitiert. Die Parasitoidengilde fuhrte 1986 den vollstandigen Zusammenbruch der Schwammspinnergradation herbei.

Biological and morphological studies on Elodia morio (Fall.) (Dipt., Tachinidae) The biology of Elodia morio, a parasite of the codling moth (Laspeyresia pomonella [L.]) was studied under laboratory conditions. For this purpose a method for artificial infection was developed. Unknown larval stages are described. E. morio was found to lay its eggs into the entrance holes of the codling moth. The eggs are swallowed by the host and the larvae hatch in the gut. One day later they can be found in the muscles of the body wall. The 2nd larval stage lives freely in the mixocoel and pierces a breathing hole when the host larvae pupates. The duration of the larval stages was determined. For better estimation of the success of parasitation, the resistance of the microtypical eggs of E. morio to desiccation was determined. Zusammenfassung Die erfolgreiche Zucht des Parasiten Elodia morio auf seinem Wirt, dem Apfelwickler (Laspeyresia pomonella [L.]) ermoglichte es, bisher unbekannte Larvenstadien zu beschreiben und die Biologie von Imagines und Larven aufzuklaren. Die Eiablage der Fliegenweibchen erfolgt an die Einbohroffnungen der Apfelwicklerraupen in die Frucht und konnte experimentell durch Kotkrumel der Wirtsraupen ausgelost werden. Die Wirtsraupen nehmen die Eier oral auf; nach dem Schlupfen im Magensaft durchdringt die Larve im ersten Stadium (LI) die Darmwand der Wirtsraupe und bohrt sich in ein Muskelbundel der Korperwand ein. Die LII lebt frei in der Leibeshohle und legt eine sekundare Atemoffnung an, sobald sich der Wirt verpuppt hat. Auch die Dauer der Larvenstadien wurde ermittelt. Die Austrocknungsresistenz der mikrotypen Eier wurde unter verschiedenen Feuchtigkeitsbedingungen untersucht.

The life-cycle of T. ampelophaga has been observed in 3 vineyards in Umbria (Central Italy) for 9 years (1976–1984) in the field and in the laboratory in order to compare the results of both. A summary is also given on world distribution, of this insect and in particular have been studied natural enemies and abiotic factors (meteorological and summer spraying), which are supposed to be dangerous to this insect. The results show the following: - the insect has only one generation per year and overwintering takes place in the bark of the vine and in stubs as larvae of second instar; - six species of parasites were found, that is 2 Chalcididae (Brachymeria intermedia Nees and Hocheria unicolor Walk.), 1 Braconidae (Apanteles ultor Reinh.), 2 Tachinidae (Zenillia libatrix [Panzer] and Exorista sp.) and 1 Trichogrammatidae (Trichogramma evanescens Westw.). The percentage of parasites is not very high so that they are not able to control the infestation of T. ampelophaga; — rainfalls, winds and high temperatures kill the pre-adult instar of T. ampelophaga but fungicide and insecticide commonly sprayed in summer are more dangerous for the insect than the previous ones. Zusammenfassung Beitrage zur Biologie und zum Massenwechsel von Theresimima ampelophaga Bayle-Barelle (Lep., Zygaenidae) Es wurden Biologie und Ethologie von T. ampelophaga sowie die klimatischen Faktoren hinsicht-lich der Sterblichkeit der larvalen Stadien dieser Art in 3 verschiedenen Weinbergen (Mittelitalien) von 1976-1984 untersucht. Es konnte gezeigt werden, das T. ampelophaga jahrlich eine Generation bildete, deren Larven im 2. Stadium unter der Baumrinde und am Sporn der Schnittstellen des vergangenen Jahres uberwinterte. Die Forschungen uber T. ampelophaga ergaben 6 Arten von naturlichen Feinden der Eier, Larven und Puppen, die wegen ihrer geringen Dichte jedoch kein wesentliches Element zur Reduktion von T. ampelophaga bildeten. Die 6 Arten sind: Tricho-gramma evanescens Westw. (Hym., Trichogrammatidae), Brachymeria intermedia Nees und Hocheria unicolor Walk. (Hym., Chalcididae), Apanteles ultor Reinh. (Hym., Braconidae). Zenillia libatrix (Panzer) und Exorista sp. (Dipt., Tachinidae). Die wichtigsten Faktoren, die den Befall durch T. ampelophaga verminderten, waren hohe Temperaturen, Regen und Wind sowie Fungizid- und Insektizid-Ausbringungen in den Weinbergen.

Overwintered larvae, and pupae of the codling moth were scraped from apple tree trunks in spring 1981–1984 and investigated for parasites and pathogenes. The total mortality ranged from 49.6 to 77.8 %. Elodia morio Fall. (Tachinidae) was the most common species among the parasites that emerged during the years (50.6 %). Possible reasons why a higher percentage of E. morio were found in this investigation as compared with other european countries are discussed. Pristomerus vulnerator Panz. (Ichneumonidae) and Ascogaster quadridentatus Wesm. (Braconidae) were the second most common (22.9 and 14.7 %, respectively). Of the cadavers collected in 1981–1982, the fungal pathogenes Beauveria bassiana (Bals.) Vuill. and Paecilomyces farinosus (Dicks, ex Fr.) Brown et Smith, accounted for an infection rate of 34.4 and 29.5 %, respectively. Totally 26.2 % of the experimentally exposed overwintering codling moth larvae were taken by birds. Although based on a small number of samples, birds showed a clear tendency to density-dependent predation. Zusammenfassung Die naturlichen Feinde des Apfelwicklers (Laspeyresia pomonella L.) (Lep., Tortricidae) und ihr Einflus auf uberwinternde Populationen in Sudschweden Uberwinterte Larven sowie Puppen des Apfelwicklers wurden 1981–1984 im Fruhling von Apfelbaumstammen geschabt und auf Parasiten und Pathogene untersucht. Die Gesamtmortalitat lag zwischen 49,6 und 77,8 %. Elodia morio Fall. (Tachinidae) war die haufigste Art unter den im Verlauf der Jahre schlupfenden Parasiten (50,6 %). Die moglichen Grunde, weshalb in dieser Untersuchung ein hoherer Prozentsatz von E. morio als in anderen europaischen Landern gefunden wurde, werden diskutiert. Pristomerus vulnerator Panz. (Ichneumonidae) und Ascogaster quadridentatus Wesm. (Braconidae) waren die nachsthaufigsten Arten (22,9 bzw. 14,7 %). In 1981 und 1982 eingesammelten, abgestorbenen Exemplaren wurden die Pilze Beauveria bassiana (Bals.) Vuill. und Paecilomyces farinosus (Dicks. ex Fr.) Brown et Smith, mit 34,4 bzw. 29,5 % gefunden. Von experimentell ausgebrachten, uberwinternden Apfelwicklerlarven wurden insgesamt 26,2 % von Vogeln gefressen. Trotz der geringen Probenzahl liesen Vogel eine deutliche Tendenz zur dichteabhangigen Pradation erkennen.

Nosema lymantriae (Protozoa, Microsporidia) was used in an experimental plot in oak grove for control of Lymantria dispar, with dosage 107 spores/m2 mainly on L3 in a density of 153 larvae/1000 leaves. Reductions of different instars reached 37.15% of larvae, 33.20% of pupae and 6.72% of emerging adults. The infection did not interfere with development of parasites (Tachinidae mainly), in contrary, the increasing immobilization of infected animals increased the attacks of parasites and predators. Including the number of hatching eggs in the next generation, the population was reduced by the infection to 1/10 of the control. Zusammenfassung Freilandversuche zum Einsatz von Nosema lymantriae gegen den Schwammspinner, Lymantria dispar L. Die Mikrosporidie Nosema lymantriae (Protozoa, Microsporidia) wurde auf einer Versuchsflache in einem Eichenbestand zur Bekampfung des Schwammspinners getestet. L3-Raupen wurden bei einer Besatzdichte von 153 Tieren/1000 Blattern mit einer Dosis von 107Keimen/m2 (in wassriger Suspension) behandelt. Die Reduktion der einzelnen Entwicklungsstadien erreichte bei den Raupen 37,15%, bei den Puppen 33,20% und bei den schlupfenden Faltern 6,72%. Die Erkrankung beeintrachtigte die Entwicklung von Tachinen nicht; im Gegenteil, die steigende Immobilitat befallener Tiere erleichterte die Angriffe der Parasiten und Pradatoren. Unter Berucksichtigung der Anzahl schlupfender Eier in der folgenden Generation, wurde durch die Mikrosporidien-Infektion eine Reduktion von 10% im Vergleich zur unbehandelten Kontrollpopulation bewirkt.