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1.
Parasitoids are known to be an important factor in the population density regulation of bark beetles. In our study of the parasitoid complex of spruce bark beetles in 2011 and 2012, we collected bark samples from trees infested with I. typographus from spruce stands in the altimontane belt of Slovenia. The samples were taken at different altitudes: 450, 700 and 1230 m above sea level. A total of 9 bark beetle species and 12 parasitoid species was found. Ips typographus was most abundant, with 93% of all species of scolytids. The parasitoid species that were found belonged mainly to the Pteromalidae and Braconidae families. By far the most abundant and frequent species was Roptrocerus xylophagorum, which represented 84% of all parasitoids and was present in all study samples. Differences in species composition, parasitoid species diversity, species abundance and parasitism rate were confirmed between locations and also between both years of our study.  相似文献   

2.
The Eucalyptus gall wasp Ophelimus maskelli (Hymenoptera: Eulophidae) and its parasitoid Closterocerus chamaeleon (Hymenoptera: Eulophidae) were observed for the first time in Portugal, in 2006 and 2007, respectively. Data on the distribution of O. maskelli in Portugal, differences in the susceptibility of two host species, Eucalyptus globulus and Eucalyptus camaldulensis, and parasitism by C. chamaeleon are given.  相似文献   

3.
The loreyi leaf worm,Mythimna (Acantholeucania) loreyi Duponchel (Lepidoptera, Noctuidae), is a pest of gramineous crops and causes significant economic damage to maize. In field surveys on maize to determine the parasitoid community and its impact on the pest in the eastern Mediterranean region of Turkey, nine parasitoid species were found associated with immature stages ofM. loreyi: The hymenopteran (Braconidae and Ichneumonidae) parasitoidsCotesia (=Apanteles) ruficrus (Haliday),Chelonus oculator Panzer,Meteorus ictericus Nees,Hyposoter didymator (Thunberg),Sinophorus sp.; and the dipteran (Tachinidae) parasitoidsPseudogonia rufifrons Wiedeman,Exorista rossica Mesnil,Gonia picea (Robineau-Desvoidy) andLinnaemya vulpina (Fallen) — the last three recorded for the first time as parasitoids ofM. loreyi in Turkey.C. ruficrus was the dominant parasitoid species, being recovered from 38.5% of the larvae collected and was also the most prevalent species, existing in 91.0% of the fields in whichM. loreyi was found. Total parasitism levels achieved by braconid species was 41.4%, by ichneumonid parasitoids 4.8%, and by tachinid parasitoids 1.9%. In a separate field experiment, seasonal population fluctuations and natural efficiency ofC. ruficrus onM. loreyi were found to be 35.1% and 42.4%, respectively. Population levels ofC. ruficrus were closely related to fluctuations in the population ofM. loreyi, with parasitism ranging between 0 and 77.3% during the study. http://www.phytoparasitica.org posting Aug. 28, 2005.  相似文献   

4.
Notes on pistachio seed wasps from two locations in the east Mediterranean   总被引:1,自引:0,他引:1  
Two seed wasps, Eurytoma plotnikovi Nikol’skaya. (Hymenoptera: Eurytomidae) and Megastigmus pistaciae Walker (Hymenoptera: Torymidae), were collected from pistachio nuts, Pistacia vera (Anacardiaceae), in Gaziantep province in Turkey and in El Harub, Judean Hills, Palestinian Authority. E. plotnikovi was clearly identified for the first time in Turkey among the reared materials, but in the past it had been recorded there by several authors under different names. The percentages of fruit infestations by these wasps in untreated pistachio orchards in Gaziantep province and in one orchard in El Harub were 69% and 81%, respectively. Gugolzia karadagae Doğanlar (Hymenoptera: Pteromalidae) was responsible for 2.2–17.5% parasitism of E. plotnikovi in Gaziantep province. So far, G. karadagae was not found in any other part of Turkey, nor in El Harub or Israel.  相似文献   

5.
为明确烟粉虱Bemisia tabaci MED隐种优势寄生蜂海氏桨角蚜小蜂Eretmocerus hayati ZolnerowichRose与浅黄恩蚜小蜂Encarsia sophia GiraultDodd对其控制效果的影响,在棉田尼龙纱网笼罩中释放烟粉虱之后,再分别单独释放海氏桨角蚜小蜂、浅黄恩蚜小蜂以及二者以不同比例组合(1∶1、1∶3、3∶1)释放,定期调查统计2种蚜小蜂对烟粉虱的寄生量和烟粉虱的种群动态。结果表明,相对于不放蜂对照,自首次放蜂后40 d开始,所有放蜂处理均能显著降低烟粉虱若虫种群密度,每100 cm~2叶片上均少于1.00头,但各处理间的烟粉虱种群密度无显著差异;海氏桨角蚜小蜂和浅黄恩蚜小蜂以3∶1比例组合释放的处理中对烟粉虱的寄生量最高,每100 cm~2棉花叶片上能达到4.25头。表明在棉田中对烟粉虱进行生物防治时,以初级寄生蜂海氏桨角蚜小蜂与复寄生蜂浅黄恩蚜小蜂为3∶1的比例释放,可以到达较好的控制效果。  相似文献   

6.
Ceutorhynchus obstrictus (Marsham) (Coleoptera: Curculionidae) is a major pest of oilseed rape in Europe and North America. The last decade has seen growing interest in the occurrence, importance and efficiacy of its parasitoids as biocontrol agents. The infestation of pods by C. obstrictus larvae and their parasitism rates were assessed in a total of nine commercially-grown crops and fifteen experimental plots of winter oilseed rape in 2004–2007. Pod samples were collected at the pod maturation stage and incubated in emergence traps. Emerged larvae, their exit holes and parasitoids were counted and identified; the percentage of infested pods and parasitism rates were calculated. Pod infestation by larvae increased continuously over the study period. The parasitism level was lowest in 2005 and increased thereafter up to 96%. The most abundant parasitoid was Trichomalus perfectus (Walker), but Mesopolobus morys (Walker) and Stenomalina gracilis (Walker) (Hymenoptera: Pteromalidae) were also reared from host larvae. This study showed that naturally-occurring ectoparasitoids of C. obstrictus were capable of becoming established as viable populations and have the potential to contribute to biological control of C. obstrictus.  相似文献   

7.
Populations of pear psylla,Cacopsylla pyri (L.) (Rhynchota: Psyllidae), and its natural enemies were sampled on pears in Antalya province during the years 2000–2002. Thirty-two species of predators and three species of parasitoids were detected to be associated withC. pyri in Antalya province. The heteropterans (especially anthocorid species) were the most abundant predator group. Among the anthocorids,Anthocoris nemoralis (Fabricius) (Heteroptera: Anthocoridae), whose population was closely related to the dynamics of the pear psylla population, was generally the principal antagonist ofC. pyri. Other species recorded during the study were the miridDeraeocoris spp., the chrysopidChrysoperla carnea L., and many coccinellid species. Although these predators are polyphagous, as are theOrius species, their populations were related to the psylla fluctuations. Among the parasitoid complex belonging to the order Hymenoptera, the encyrtidTrechnites psyllae (Ruschka) was the only primary parasitoid. Two hyperparasites,viz., Syrphophagus mamitus (Walker) andPachyneuron aphidis (Bouché) (Encyrtidae and Pteromalidae, respectively), were detected in the surveys. Also, this study revealed new information concerning the pear psylla parasitoid complex in Turkey. WhileT. psyllae andS. mamitus are new records to Turkish parasitoid fauna,C. pyri is a new host record forP. aphidis. The population development and abundance of pear psylla and its natural enemies, as well as the parasitization rates in treated and untreated pear orchards, are presented here. http://www.phytoparasitica.org posting May 6, 2004.  相似文献   

8.
Infestation levels and parasitism of lepidopteran stemborers on maize were assessed in four agroecological zones (AEZ) in Uganda. The indigenous noctuidBusseola fusca Fuller (Noctuidae) and the invasiveChilo partellus Swinhoe (Crambidae) were the most important stemborers recorded.C. partellus represented 77% of the stemborers in the Eastern AEZ whileB. fusca was dominant in the other AEZs, accounting for 60–79%. The proportion of infested plants was between 16% and 45% and borer density between 0.2 and 1.0 borers per plant. There was no clear relationship between damage and stem tunneling, which is often used to estimate yield loss.Telenomus busseolae Gahan (Scelionidae), the only egg parasitoid recovered, caused parasitism of up to 46% onB. fusca eggs. Several larval and pupal parasitoid species were recorded. The most common were the indigenous braconidCotesia sesamiae and the introducedCotesia flavipes, which are larval parasitoids ofB. fusca andC. partellus, respectively. Mean parasitism by the indigenousC. sesamiae ranged between 2.0% and 29.4% onB. fusca and from 0 to 13% onC. partellus. C. flavipes was recovered at most locations with parasitism of 0–30.5% onC. partellus and 0–12% onB. fusca; the latter was probably the result of multiparasitism as laboratory studies have shown that it was not a suitable host forC. partellus. Results indicated further that the parasitoid has not attained equilibrium 5 years after its introduction. http://www.phytoparasitica.org posting Nov. 20, 2006. Teddy Matama-Kauma died suddenly in an accident on Dec. 10, 2006, while this paper was in press.  相似文献   

9.
Five populations of the crambid stemborerChilo partellus (Swinhoe) and one of the noctuid borerBusseola fusca (Fuller) from Zimbabwe were evaluated for their suitability for immature development of the exotic braconid larval parasitoidCotesia flavipes Cameron. Successful parasitoid development occurred only onC. partellus but parasitism as well as egg-to-adult development time did not vary among the five populations. Smallest parasitoid broods, and sex ratios as the proportion of female offspring, however, were produced withC. partellus from the Muzarabani area of Zimbabwe.Co. flavipes became successfully established in five out of eight locations, where it had been released in July 1999 and the 2004/05 summer season. Its spread and impact, however, still need to be assessed. http://www.phytoparasitica.org posting March 10, 2008.  相似文献   

10.
The species of the genus Yponomeuta Latreille (Lepidoptera: Yponomeutidae) are known as ermine moths and can be found on various host plant species, sometimes appearing as pests. They are attacked by a wide range of parasitoids. We studied parasitoid complexes of several communities in Austria, Poland, Serbia, Slovenia and Sweden during 2014–2018. From four species, Yponomeuta cagnagella (Hübner), Yponomeuta evonymella (Linnaeus), Yponomeuta malinellus Zeller and Yponomeuta padella (Linnaeus), we reared 15 parasitoid species of seven hymenopteran and one dipteran family. In this study, the family Ichneumonidae is the most numerous, while Ageniaspis fuscicollis (Dalman) (Hymenoptera: Encyrtidae) was found in all four Yponomeuta species. Within reared parasitoids, A. fuscicollis is new record for Slovenia and Austria, Baryscapus evonymellae (Bouché) (Hymenoptera: Eulophidae) and Diadegma armillatum (Gravenhorst) (Hymenoptera: Ichneumonidae) are new records for Slovenia and Agrypon canaliculatum (Ratzeburg) (Hymenoptera: Ichneumonidae), Dolichogenidea dilecta (Haliday) (Hymenoptera: Braconidae), Elasmus steffani Viggiani (Hymenoptera: Eulophidae), Herpestomus brunnicornis (Gravenhorst) (Hymenoptera: Ichneumonidae), Trieces tricarinatus (Holmgren) (Hymenoptera: Ichneumonidae) and Mesochorus nuncupator (Panzer) (Hymenoptera: Ichneumonidae) are new records for Serbia. Also, Yponomeuta cagnagella is a new host record for Pteromalus semotus (Walker) (Hymenoptera: Pteromalidae) and Y. padella for E. steffani. Finally, we reviewed parasitoids of European Yponomeuta species and their associated host plants. In total 154 species are recorded from nine hymenopteran and one dipteran family.  相似文献   

11.
The present study was conducted to determine egg and larval parasitoids of the beet armywormSpodoptera exigua Hübner (Lepidoptera: Noctuidae), which is an important but sporadic pest in Turkey. High beet armyworm population levels were recently observed in fields of first and second crop maize in the southeast Mediterranean region of Turkey. The parasitoid species complex and its impact on the pest were analyzed in a 4-year study in first and second crop maize. The braconid larval parasitoidsMicroplitis rufiventris Kokujev,M. tuberculifer Wesmael,Meteorus ictericus Nees,Chelonus obscuratus (Herrich Schäffer) (an egg-larval parasitoid),Apanteles ruficrus (Haliday); the ichneumonid larval parasitoidsHyposoter didymator (Thunberg) andSinophorus xanthostomus Gravenhorst; and the egg parasitoidTrichogramma evanescens (Westwood) were found to be the natural enemies attacking the pest. Among the parasitoid species the solitary endoparasitoidH. didymator was the most prevalent species, being reared from 40.5% of the parasitized larvae found. Higher parasitism rates were recorded on first crop than on second crop maize in every year. Possible reasons for this difference in larval parasitism between two growing seasons include lower population of the pest and reduced insecticide applications in first crop maize fields which permitted higher parasitism. However, parasitoid activity was insufficient to counterbalance the population growth of the pest on subsequent second crop maize.  相似文献   

12.
The loreyi leaf worm,Mythimna (Acantholeucania) loreyi (Duponchel) (Lepidoptera: Noctuidae), is a serious pest of gramineous crops and reduces yields in maize plantations. This study was undertaken to determine the tachinid parasitoid complex ofM. loreyi in the southeast Anatolian region of Turkey. Four tachinid species were found:Pseudogonia rufifrons (Wiedemann),Exorista larvarum (Linnaeus),Drino imberbis (Wiedemann) andLinnaemya neavei Curran were reared from field-collectedM. loreyi larvae. Of the four tachinid speciesM. loreyi is a new host record forE. larvarum andD. imberbis. L. neavei was recorded for the first time in Turkey and was the most frequently encountered parasitoid in this study. Total parasitism level was 7.1% in 2003 and 15.5% in 2004. http://www.phytoparasitica.org posting Jan. 16, 2007.  相似文献   

13.
We first discuss the diversity of fruit fly (Diptera: Tephritidae) parasitoids (Hymenoptera) of the Neotropics. Even though the emphasis is on Anastrepha parasitoids, we also review all the information available on parasitoids attacking flies in the genera Ceratitis, Rhagoletis, Rhagoletotrypeta, Toxotrypana and Zonosemata. We center our analysis in parasitoid guilds, parasitoid assemblage size and fly host profiles. We also discuss distribution patterns and the taxonomic status of all known Anastrepha parasitoids. We follow by providing a historical overview of biological control of pestiferous tephritids in Latin American and Florida (U.S.A.) and by analyzing the success or failure of classical and augmentative biological control programs implemented to date in these regions. We also discuss the lack of success of introductions of exotic fruit fly parasitoids in various Latin American countries. We finish by discussing the most pressing needs related to fruit fly biological control (classical, augmentative, and conservation modalities) in areas of the Neotropics where fruit fly populations severely restrict the development of commercial fruit growing. We also address the need for much more intensive research on the bioecology of native fruit fly parasitoids.  相似文献   

14.
Abstract The parasitoid complex of Dasineura saliciperda (Dufour) (Diptera, Cecidomyiidae) on Salix fragilis L. was studied in 1997 and 2002 in two localities in Bulgaria. As a result, 5 species from 3 families of Chalcidoidea (Hymenoptera) were reared from pest galls: Eurytoma afra Boheman, Eurytoma salicis Walker (Eurytomidae), Torymus microcerus (Walker) (Torymidae), Gastrancistrus sp. and Mesopolobus sp. (Pteromalidae). E. afra and T. microcerus are new species for the fauna of Bulgaria, and E. salicis – a new parasitoid of the host. Total parasitism of D. saliciperda in the studied years ranged between 44.1 and 53.5 %. E. afra was the most important, destroying 21.9-53.5 % of the pest.  相似文献   

15.
Bactra venosana Zeller (Lepidoptera: Tortricidae) is the predominant natural enemy ofCyperus rotundas L. in Bangalore, India. Although the insect was found to have potential, it was incapable of suppressing the weed due to low incidence. Laboratory studies involving field-collected insect stages revealed that heavy parasitism of eggs byTrichogrammatoidea bactrae Nagaraja (Hymenoptera: Trichogrammatidae) was the most important mortality factor suppressing its potentiality.  相似文献   

16.
Recognizing the potential significance of using nuclear techniques in biological control, investigations were conducted on the rearing of parasitoids of the peach fruit-fly, Bactrocera zonata (Saunders) (Diptera: Tephritidae) to lead to a greater flexibility in the use of irradiated hosts. For improving mass production of the biological control agents, the use of irradiated fruit-fly larvae at the dose of 15 Gy proved useful for enhancing the parasitism and adult emergence of the larval parasitoid, Trybliographa daci (Weld) (Hymenoptera: Eucoilidae) due to no negative repercussions on parasitoid development. Overall, parasitism by the parasitoid increased with age of the host larvae; however, significantly higher parasitism occurred on 4 d-old irradiated larvae of B. zonata compared to those aged 5 d. The female parasitoids preferred the irradiated larvae, and significantly higher numbers of larvae were parasitized compared with non-irradiated larvae. There was no significant difference in adult parasitoid emergence with respect to the sex of the host. A radiation level of 80 Gy was the best dose for rearing of the pupal parasitoid, Dirhinus giffardii (Silvestri) (Hymenoptera: Chalcididae) owing to broad tolerances in the use of irradiation for the rearing of fruit-fly's parasitoids. Percentage parasitism by D. giffardii varied with host pupal age, and the preference of the female parasitoid was lower on 48 h old host pharate pupae due to optimum size and mass of host. Present findings further revealed that the 24 h old host pupae of B. zonata were relatively more suitable for the maximum parasitism and progeny production of D. giffardii. Parasitisms by D. giffardii and T. daci were significantly higher on B. zonata host when parasitoids were released at a density of 3000 individuals per acre (7500 per hectares) than the other release rates of parasitoids for the management of fruit-flies in mango orchards. The implementation of these findings ought to help improve the mass production of parasitoids and the effectiveness of releases of biocontrol agents for control of B. zonata in mango plantations.  相似文献   

17.
Samples were collected from southern Greece during 1996–2000 in order to investigate the presence of parasitoids onAphis gossypii Glover infesting several citrus species. The species of aphidiines found to have a significantly different preference forA. gossypii wereAphidius colemani Viereck,Aphidius matricariae Haliday,Diaeretiella rapae (M’Intosh),Ephedrus persicae Froggat,Lysiphlebus testaceipes (Cresson),Binodoxys acalephae (Marshall) andBinodoxys angelicae (Haliday). In another sampling experiment, the relative abundance of aphidiine parasitoids on aphids infesting orange and tangerine trees was studied in southern Greece (Nea Kios) in 1996 and 1997.A. gossypii constituted the largest part of the aphid population and was the only species parasitized.B. angelicae andA. colemani were the most abundant parasitoid species. The parasitization rate differed among the parasitoid species.B. angelicae had the highest colonization rate in centrally located and large host (A. gossypii) groups, whereasA. colemani was found in more isolated and relatively small host groups. The percentage of parasitism byB. angelicae was high mainly in large host groups, whenB. angelicae was the only parasitoid present. However, in cases of coexistence ofB. angelicae withA. colemani with hyperparasitoids, in the same sampling unit, the percentage of parasitism was relatively low. http://www.phytoparasitica.org  相似文献   

18.
The effectiveness of inundative releases of four strains of the egg parasiteTrichogramma (Hymenoptera, Trichogrammatidae) to control five lepidopterous species infesting Brussels sprouts crops in the Netherlands was examined in small-scale field experiments in 1982–1985. Strains were selected on the basis of behavioural characteristics investigated in laboratory experiments, i.e. parasitization activity at low temperature and host-species preference.Mamestra brassicae (Noctuidae) was the most abundant host species. Its density usually averaged between 0.5 and 2.0 eggs/plant throughout most of the season (June–September). A very high peak density of 12 eggs/plant occurred in 1982. In other years the peak was below 2.5 eggs/plant.Correspondence between the observed patterns of parasitism and behavioural characteristics of the strains was in general present. A strain ofT. evanescens (no. 57), with a high activity at 12°C, performed best againstM. brassicae. However, even its highest rate of parasitism (52%) was not sufficiently effective. A strain ofT. maidis (no. 11) performed best againstPieris brassicae andP. rapae (Pieridae), but parasitism remained low (<30%) and was generally limited to peak densities (<0.5 eggs plant) occurring in 1982 and 1985.Plutella xylostella (Yponomeutidae) was an abundant species in some years, but parasitism of its eggs was never observed. Egg densities ofEvergestis forficalis (Pyralidae) remained low in all years. The relationship between parasitims and host density and the influence of the parasite-release rate are discussed. Low host densities may have been a limiting factor for effective parasitism.Samenvatting In spruitkool kan schade veroorzaakt worden door rupsen van vijf soorten Lepidoptera. Inundatieve biologische bestrijding met de eiparasietTrichogramma (Hymenoptera, Trichogrammatidae) zou een alternatief kunnen zijn voor intensieve chemische gestrijding. In veldexperimenten (1982–1985) is de effectiviteit van vierTrichogramma spp. stammen vergeleken om de uitkomsten van laboratoriumonderzoek naar criteria voor de selectie van geschikte natuurlijke vijanden te evalueren. Selectiecriteria zijn gebaseerd op eigenschappen van het zoek- en parasiteringsgedrag van de parasieten, o.a. parasiteringsactiviteit bij lage temperatuur en gastheer-preferentie. Mamestra brassicae (Noctuidae) was de talrijkste gastheersooort, met een gemiddelde dichtheid van 0,2–2,0 eieren/plant gedurende een groot deel van het seizoen (juni–september). Een extreem hoge piekdichtheid (12 eieren/plant) deed zich voor in 1982. In andere jaren was de piekdichtheid ongeveer 2,5 eieren/plant. Eieren vanM. brassicae werden het meest geparasiteerd door stam 57 (T. evanescens), maar zelfs het hoogste gemiddelde seizoenspercentage parasitisme (52%) was niet voldoende voor een effectieve bestrijding. EenT. maidis stam (11) gaf de beste resultaten tegenPieris brassicae enP. rapae (Pieridae), maar parasitisme was laag (<30%) en vrijwel beperkt tot piekdichtheden hoger dan 0,5 eieren/plant, die voorkwamen in 1982 en 1985.Plutella xylostella (Plutellidae) was soms talrijk, maar eiparasitisme leek niet voor te komen. De dichtheid vanEvergestis forficalis (Pyralidae) was gering in alle jaren.Relatief lage gastheerdichtheden kunnen een beperkende factor geweest zijn voor het optreden van een effectieve percentages eiparasitisme. De resultaten tonen aan dat er een overeenstemming is tussen selectiecriteria die in het laboratorium zijn onderzocht en de effectiviteit van geselecteerde stammen in het veld.  相似文献   

19.
The first parasitoid species reared from a population of the cedar aphid,Cinara cedri Mimeur, 1935 (Hemiptera: Aphididae), from the peninsula of Anatolia in Turkey is described.Pauesia anatolica (Hymenoptera: Braconidae, Aphidiinae) is closely related to some species of thelaricis group ofPauesia from which it differs in the number of antenomers, the propodeum and features of the female genitalia. Its potential use as a natural enemy in areas where the aphid has been introduced is discussed. http://www.phytoparasitica.org posting Aug. 28, 2005.  相似文献   

20.
A new hymenopteran aphid parasitoid species (Praon uroleucon sp. n.) fromUroleucon sp. infestingCarduus acanthoides L. is described from Yugoslavia. It is diagnosed and illustrated with scanning electron microscope photographs and line drawings. The new species is placed in thePraon dorsale species group, and a key to species of that group is provided. http://www.phytoparasitica.org posting Dec. 9, 2002.  相似文献   

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