Note: Tachinid parasitoids (Diptera: Tachinidae) of<Emphasis Type="Italic">Mythimna (Acantholeucania) loreyi</Emphasis> in the southeast Anatolian region of Turkey

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.     

Egg and larval parasitoids of the beet armyworm<Emphasis Type="Italic">Spodoptera exigua</Emphasis> on maize in Turkey

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.     

The parasitoid complex ofLiriomyza cicerina on chickpea (Cicer arietinum)

Liriomyza cicerina (Diptera: Agromyzidae) is an important pest on chickpea in Turkey. The objective of this study was to determine the parasitoids and rates of parasitism ofL. cicerina on chickpea (Cicer arietinum L.) during the 2005 and 2006 seasons in ?anl?urfa province, Turkey. Leaves with mines were sampled weekly and kept in the laboratory to observe and count emerging leafminer and parasitoid adults. Eight parasitoid species were collected: the braconidsOpius monilicornis Fischer andOpius tersus Foerster and the eulophidsDiaulinopsis arenaria (Erdös) andNeochrysocharis formosa (Westwood), which occurred in both the winter and summer seasons;Diglyphus crassinervis Erdös,Neochrysocharis ambitiosa Hansson,Neochrysocharis sericea (Erdös) andPediobius metallicus (Nees), which occurred only in the summer growing areas.Diaulinopsis arenaria was the predominant parasitoid with 4–7.7% parasitism rate whileN. ambitiosa andO. monilicornis were the second and third most predominant species. The results of these trials show that sinceDia. arenaria occurred throughout every season, it could potentially be used for control of the leafminerL. cicerina.     

Contribution of Biological Control to Integrated Pest Management of Tephritid Fruit Flies in the Tropics and Subtropics

The biological control of pest tephritid flies using parasitoids has been successful in relatively few subtropical and tropical regions. The best documented successes were in Hawaii and Florida, USA, Fiji and southern Europe. There were relatively limited successes in Australia, Costa Rica and Mexico. With the accidental establishment of new pest tephritids, such as Bactrocera latifrons (Hendel) in Hawaii or Bactrocera papayae Drew and Hancock in Australia, foreign exploration for new parasitoids is essential. A renewal of interest in classical biological control has recently occurred, although not at the same level as in the 1940s and 1950s. New parasitoid species are currently being obtained for several tephritids, such as Ceratitis capitata (Weidemann), B. latifrons and Anastrepha suspensa (Loew). The advances in mass rearing and quality control technology for parasitoids has enabled researchers to perform large-scale field testing of these parasitoids to determine the potential of augmentative releases. Numerous studies on the augmentative release of parasitoids have been done. Historically, the larval—pupal parasitoid Diachasmimorpha longicaudata (Ashmead) has been the most frequently studied parasitoid, due to the ease of rearing this species. However, recent successes in rearing other species with different biologies, e.g. the egg—pupal parasitoid Biosteres arisanus (Sonan), the gregarious eulophid, Tetrastichus giffardianus (Silvestri) and the pupal parasitoid, Coptera sp., will enable researchers to broaden the repertoire of parasitoid species for the future. Both successes and failures in augmentative releases have occurred. Without knowledge of the behavioural ecology of parasitoids, the reasons for success or failure can only be surmised. Recent research on the dispersal and host habitat finding of tephritid parasitoids will provide insights into improving augmentation and conservation strategies. The integrated pest management (IPM) of tephritid flies in the tropics has been less well-developed than research and programmes for tephritids in temperate zones. Significant emphasis is now being placed on the development of quarantine treatment methods that are environmentally sound; thus IPM will take a larger role. Several existing pest management strategies are reviewed which show the potential for compatibility with the activities of tephritid parasitoids. These include trap cropping, insecticides with selective toxicity to the target pests, mass trapping with parapheromones, the sterile insect technique and field sanitation.     

Distribution and relative importance of lepidopteran cereal stemborers and their parasitoids in Uganda

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.     

Note:Cnaemidophorus rhododactyla, a NewRosa spp. Pest for Turkey, and its new parasitoids, a NewRosa spp. Pest for Turkey, and its new parasitoids

In the present study,Cnaemidophorus rhododactyla (Denis & Schiffermüller) (Lepo Pterophoridae) was noted for the first time as a pest ofRosa spp. in Turkey. The larva ofC. rhododactyla makes a cavity by feeding in the flower-bud and destroys at least 60% of the mass of the flower-bud. There are approximately 12 species ofRosa in Erzurum and Kars provinces, butRosa dumalis Bechst. andR. subcanina L. suffered more damage than the otherRosa species. One species of Tachinidae (Diptera) —Pseudoperichaeta palesoidea (Robineau-Desvoidy), and two species of Ichneumonidae (Hymenoptera) —Sinophorus turionus (Ratz.) andScambus brevicornis Gravenhorst, were reared as larval parasitoids ofC. rhododactyla. C. rhododactyla is a new host record for these parasitoids. Additionally,S. turionus is a new record for the Turkish fauna.     

The profitability of maize–haricot bean intercropping techniques to control maize stem borers under low pest densities in Ethiopia

Lepidopteran stem borers are the main pests of cereals in Ethiopia. In recent years, habitat management techniques, which aim at increasing plant biodiversity through mixed cropping, have gained increased attention in stem borer control. In the present study, the profitability of mixed cropping of maize with haricot beans at different ratios and the effect on infestation of maize by stem borers, yield and borer parasitism were studied in Melkassa and Mieso, Ethiopia, in a field experiment under natural infestation. In Melkassa, pest infestations were too low for the cropping system to affect pests, plant damage and yields significantly, whereas in Mieso, where the pest densities were high, intercropping of maize with beans at ratios of 1:1 to 2:1 significantly decreased borer densities compared with pure maize stands. Chilo partellus (Swinhoe) and Cotesia flavipes. (Cameron) were the major stem borer and parasitoid species, respectively, recorded both at Melkassa and Mieso. Borer parasitism was higher at Mieso than at Melkassa and tended to increase with the increase of the haricot bean ratio in the intercropping system. Land equivalent ratios of >1 indicated higher land use efficiency in mixed compared with sole cropping, even if pest densities were low.     

Bark-Beetle Parasitoids Population Surveys Following Storm Damage in Spruce Stands in the Vosges Region (France)

This paper presents the results of a long-term study designed to follow the population dynamics of hymenopteran parasitoids associated with Ips typographus L. (Coleoptera: Scolytidae) in northeastern France (Alsace and Vosges) in spruce stands devastated by the December 1999 storms. Population densities were estimated by periodic samplings in the pre-emerging insect populations developing under the bark of attacked trees. Data were collected between July 2000 and October 2001. I. typographus population density (per m²) increased respectively by 28%, 105%, and 212% in one year in the three sites surveyed. Six hymenopteran ectoparasitoids were found: Coeloides bostrichorum Giraud and Dendrosoter middendorffi Ratzeburg (Hymenoptera: Braconidae); Rhopalicus tutela (Walker), Roptrocerus xylophagorum (Ratzeburg), Roptrocerus mirus (Walker) and Dinotiscus eupterus (Walker) (Hymenoptera: Pteromalidae). After two years, the parasitoid populations increased in terms of average density but parasitism rates remained at a relatively low level, ranging from 0% to 40%, with 60% of the trees having a parasitism rate below 5%. Data outlined the recurrent coexistence of competing parasitoid species.     

Aphid parasitoids (Hymenoptera: Braconidae: Aphidiinae) on citrus: Seasonal abundance, association with the species of host plant, and sampling indices

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     

Natural enemies of the pear psylla<Emphasis Type="Italic">Cacopsylla pyri</Emphasis> in treated<Emphasis Type="Italic">vs</Emphasis> untreated pear orchards in Antalya,Turkey

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.     

Parasitoid complex of<Emphasis Type="Italic">Cameraria ohridella</Emphasis> (lepidoptera: Gracillariidae) in Serbia

Fourteen species in two families of the order Hymenoptera: Ichneumonidae (1 sp.) and Eulophidae (13 spp.), were recorded during the study ofCameraria ohridella parasitoids at eight localities in Serbia. Among the observed parasitoids, the most significant species wereMinotetrastichus frontalis, Pediobius saulius, Pnigalio agraules andClosterocerus trifasciatus. In addition, at some localities the speciesMinotetrastichus platanellus andCirrospilus talitzkii were also significant. The parasitoids do not have a significant effect on the abundance ofC. ohridella because in the majority of study samples parasitism levels did not exceed 20%. http://www.phytoparasitica.org posting Feb. 23, 2004.     

Parasitoids Associated with <Emphasis Type="Italic">Mussidia</Emphasis> spp. (Lepidoptera: Pyralidae) in Kenya

The pyralid Mussidia nigrivenella, a pest of cotton, maize and Phaseolus bean in West Africa, has never been reported as a crop pest in East and Southern Africa, although reportedly it exists in the wild. It is hypothesized that the difference in pest status of M. nigrivenella between western and eastern Africa was either due to differences in natural enemy compositions or that there exist several populations and/or species of Mussidia, which vary in their host plant range. Thus, a catalogue of parasitoids of Mussidia spp. was established through surveys in mid-altitude and coastal Kenya, between 2006 and 2007. Mussidia spp. eggs, larvae and pupae were collected from fruits of plants known to host Mussidia spp. and were examined for parasitoid-related mortality. The trichogrammatid Trichogrammatoidea sp. nr. lutea was obtained from eggs of Mussidia fiorii. A braconid egg-larval parasitoid, Phanerotoma sp., was reared from the larvae of unknown species of Mussidia (which we are referring to as Mussidia “madagascariensis”, Mussidia “quanzensis”) and M. fiorii, while the bethylid Goniozus sp. and the braconid Apanteles sp. were obtained from Mussidia nr. nigrivenella. Moreover, the ichneumonid larval parasitoid Syzeuctus sp. was obtained from M. fiorii, while the tachinid Leskia sp. was obtained from Mussidia “madagascariensis”. Overall, mortality caused by parasitoids was negligible; hence they were not considered key mortality factors in the population dynamics of the Mussidia spp. in Kenya.     

Natural parasitism of<Emphasis Type="Italic">Chrysoperla carnea</Emphasis> by hymenopterous parasitoids in cotton-growing areas of Çukurova,Turkey

A 4-year study of parasitoids attackingChrysoperla carnea (Stephens) in the cotton fields of Çukurova, Turkey, revealed the activities of three principal taxa:Telenomus sp. nr.suvae attacks the eggs ofC. carnea: Catolaccus sp. andBaryscapus sp. are larval and pupal parasitoids, respectively. In general, percent egg parasitism increased starting from the second half of June and into July, then decreased until the beginning of August before rising again at the end of growing season. During the early season, weekly parasitism was found to be as high as 94%. Overall, seasonal egg parasitism varied between 13.6% and 62.0% among all study sites. According to the results of a one-year field study at Hac?ali, total larval and pupal parasitism was found to be 12.5% and 55.6%, respectively. Therefore, different factors influencing the effectiveness of the generalist predatorC. carnea against cotton pests, and the differential effects of cotton treatments on both host and parasitoids, need to be evaluated.     

Effect of different hosts onThaumetopoea pityocampa populations in northeast Portugal

A study was carried out at the Natural Park of Montesinho, NE Portugal, in order to evaluate the effect of different pine species (Pinus pinaster Ait.,P. nigra Arn. andP. sylvestris L.) onThaumetopoea pityocampa populations. The structure of the egg batches, the impact of the egg parasitoids on natural mortality of the pest and the species of parasitoids present, as well as their emergence dynamics, were analyzed. The length of the egg batches varied among pine species with the longest ones onP. nigra. The mean number of eggs per batch differed betweenP. sylvestris and the two other hosts studied, with fewer eggs per batch on the first. No differences were found in the size of eggs among pine species. The egg mortality varied between 25.8% and 33.0%, with no differences among hosts. Parasitism was the main cause of death.Baryscapus servadeii (Mercet.) was the most abundant parasitoid species, followed byOoencyrtus pityocampae (Dom.) andTrichogramma embryophagum Htg.B. servadeii dominated in the egg batches collected fromP. pinaster andP. nigra, whereasO. pityocampae was most frequent onP. sylvestris. The emergence ofB. servadeii started in the middle of March and continued until August, with the emergence peak at the end of May. The emergence ofO. pityocampae started at the end of April and continued throughout September, with maximum values in June. http://www.phytoparasitica.org posting Sept. 20, 2006.     

Factors associated with mortality of the overwintering generation of<Emphasis Type="Italic">Sesamia nonagrioides</Emphasis> under field conditions

Factors affecting overwintering mortality in the Mediterranean corn stalk borer,Sesamia nonagrioides Lefebvre (Lepidoptera: Noctuidae), were investigated under field conditions in the southeast Mediterranean region of Turkey. During two consecutive years larvae and pupae were sampled from December to April in maize plots sown on three different dates. Field-collected larvae and pupae were reared and the emerged parasitoids were recorded. An effect of sowing date on total numbers ofS. nonagrioides was found with reduced populations in the early sown plots. Larval parasitism did not significantly affect overwintering mortality.Habrobracon hebetor (Say) (Hymenoptera: Braconidae) caused 11% parasitism and was found only in the first year of the study. Pupal parasitoids were predominantlyIchneumon sarcitorius caucasicus Meyer,Barichneumon sp. andPimpla spuria Gravenhorst (Hymenoptera: Ichneumonidae) and the parasitism level was 11% in both years of the study.     

基于DNA条形码对粘虫四种近缘种的鉴定与亲缘关系分析

为开发快速、准确的粘虫Myth imna separata (Walker)近源种鉴定技术,通过线粒体COI基因DNA条形码技术对在野外采集的4种粘虫近缘种——白点粘夜蛾Leucania loreyi、淡脉粘夜蛾L.roseilinea、瘠粘夜蛾 L.pallidior和虚研夜蛾Aletia pseudaletiana的COI基因片段进行序列分析,并对4种粘虫近缘种同粘虫和GenBank中其它6种粘虫近缘种之间的亲缘关系进行了分析.结果表明,克隆得到白点粘夜蛾、淡脉粘夜蛾、瘠粘夜蛾和虚研夜蛾大小为658 bp的COI基因片段,与粘虫COI基因片段的核苷酸序列同源性依次为93.31％、92.86％、91.95％和90.88％,遗传距离分别为0.067、0.071、0.081和0.091;所编码的219个氨基酸序列同源性依次为100.00％、100.00％、99.09％和99.09％.与其它6种粘虫近缘种的COI基因片段序列分析中,白点粘夜蛾和淡脉粘夜蛾与粘虫、一点粘虫Mythimna unipuncta、仿劳粘夜蛾L.insueta、白脉粘夜蛾L.venalba聚为1个亚群,亲缘关系较近;瘠粘夜蛾和虚研夜蛾与白杖研夜蛾A.lalbum、角线研夜蛾A.conigera、秘夜蛾M.turca聚为1个亚群,亲缘关系较近.表明4种近缘种与粘虫的亲缘关系由远到近依次为白点粘夜蛾、淡脉粘夜蛾、粘瘠粘夜蛾和虚研夜蛾.     

Species composition, structure and impact of larval parasitoids of poplar twig borer,Gypsonoma aceriana (Dup.) (Lepidoptera, Tortricidae), on poplar ornamental trees in Sofia

Studies on the species composition and structure of parasitoid complex of poplar twig borer,Gypsonoma aceriana (Dup.), on poplar ornamental trees in Sofia and their role in reducing the number of this pest have been conducted during the period 1990–1997. Six larval parasitoids—Bracon variator Nees,Orgilus obscurator (Nees),Microdus tumidulus Nees,Apanteles erevanicus Tob. (Braconidae),Pristomerus rufiabdominalis Ucida andPristomerus vulnerator (Panz.) (Ichneumonidae) were identified. Most numerous wereM. tumidulus (41.0%),A. erevanicus (30.6%) andP. rufiabdominalis (19.1%).A. erevanicus andM. tumidulus were dominating during the different years. The parasitoids ofG. aceriana were solitary, asB. variator is an ektoparasite, and the rest—endoparasites. They attack young host larvae and emerge at the end of the pupal stage. The life cycle of parasitoids, that have double generation, are well synchronised with the pest development. This was expressed in the high levels of parasitism, which in some cases reached 61.5%, and as a whole for the different generations they were 5.9–44.4%.A. erevanicus andM. tumidulus were the most important in reducing the number of the pest.     

Studies on Aleurothrixus floccosus (Maskell) (Homoptera, Aleyrodidae) and its parasitoid, Cales noacki Howard (Hymenoptera, Aphelinidae) in the East Mediterranean Region of Turkey

Survey studies of Aleurothrixus floccosus (Maskell) (Homoptera, Aleyrodidae) and its parasitoid Cales noacki Howard (Hymenoptera, Aphelinidae) were made in 4 provinces; namely Adana, Mersin, Hatay and Osmaniye, which are the main citrus growing areas of the East Mediterranean region of Turkey. Inoculative parasitoid releases were made in regions where no or low natural parasitism occurred after obtaining preliminary results on presence of the parasitoid. The population dynamics of A. floccosus and C. noacki were examined in Silifke (Mersin), Dörtyol (Hatay) and Yüreir (Adana), where the A. floccosus population was remarkably high at the beginning of the study in 1999. However, after parasitoid release, the pest population declined in all the sites and did not attain the same high levels again. Five predators, three parasitoids and one entomopathogen species were determined as natural enemies of A. floccosus. In addition, seven plant species, six of them belong to Rutaceae, were found as host plants for A. floccosus.     

两种蚜小蜂对烟粉虱MED隐种的田间笼罩控效评价

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。     

Ecological data on predators ofParlatoria pergandii on sour orange trees in southern Greece

The present study was carried out in southern Greece during 1993-1995 on sour orange trees infested with the diaspididParlatoria pergandii Comstock. The activity of the natural enemies of the scale, the composition of their population during the year as well as their relation with hymenopterous parasitoids of coccinellids, were studied.P. pergandii was parasitized by a hymenopterous endoparasite of the genusEncarsia and the extent of parasitization ranged between 5.2% and 14.1%. The observed predators were the coccinelidsChilocoms bipustulatus Linnaeus andRhyzobius lophanthae Blaisdell and the nitidulidCybocephalus fodori Endrödy-Younga. The predominant predator wasR. lophanthae (84.3% of the larvae and 73.3% of the adults), which was active throughout the whole year in all of its developmental stages. Second most abundant was the predatorC. bipustulatus (15.7% of the larvae and 20% of the adults) and third the predator C.fodori (6.7% of the adults). Larvae ofC. bipustulatus were observed to be parasitized by the hymenopterous parasitoidsHomalotylus flaminius Dalman (Encyrtidae) andTetrastichus coccinellae Kurdjumov (Eulophidae). The parasitization percentage increased gradually from 4% in mid June to 94% around the end of September. Laboratory tests confirmed that the above mentioned parasitoids cannot infest larvae or nymphs ofR. lophanthae.