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1.
The ability of female parasitoids (Chelonus insularis Cresson,Telenomus heliothidis Ashmead, andTrichogramma pretiosum Riley) to distinguish between parasitized and unparasitized tobacco budworm,Heliothis virescens (F.), eggs was determined in laboratory studies. All 3 species were relatively efficient at detecting eggs that were previously parasitized by conspecific females.T. heliothidis andT. pretiosum were able to discriminate on the basis of external examination of host eggs, whereasC. insularis appeared to examine hosts internally as well as externally. In interspecific tests, no species readily rejected eggs parasitized by the other 2 species.  相似文献   

2.
Rami Kfir 《BioControl》1983,28(4):345-353
The effect of host density on parasitism byTrichogramma pretiosum Riley was studied by exposing groups of 150, 300, 600 or 1200 eggs of potato tuber moth to 2, 4 or 8 female parasites per group. The parasite exhibited a type 2 functional response. As host density increasedT. pretiosum parasitised more hosts, but at a decreasing rate. The attack coefficient (a′) decreased as parasite density increased, whereas the handling time (T h ) remained almost constant. The search rate (a) decreased with increasing host density.T. pretiosum responded to increasing host density by increasing the number of its encounters with hosts and the number of hosts it parasitised only up to host density of 300 when the parasite density was 2 and up to host density of 600 when the parasite densities were greater and then remained almost constant. The observed incidence of parasitism was higher than that expected on the assumption that the parasites behaved the same at higher host densities as at the lowest. When parasite density was raised from 2 to 8 females per group the percentage of female progeny fell from about 73 to about 48%. A 2-fold increase in the number of female progeny was observed when parasite density was reduced from 8 to 2 and also when the host density was raised from 150 to 1200 eggs.  相似文献   

3.
SubgenusLathromeromina nov. of the genusLathromeromyia with a type speciesLathromeromyia (Lathromeromina) tingiphaga sp. nov. has been described and illustrated. Four species of Tingid hosts and their host plants are recorded.  相似文献   

4.
SubgenusEpoligositina nov. of the genusEpoligosita with a type speciesEpoligosita (Epoligositina) duliniae sp. nov., a new record as egg parasite of the morinda Tingid,Dulinius conchatus Dist. has been described and illustrated.  相似文献   

5.
J. H. Brower 《BioControl》1983,28(4):355-361
Eggs were collected fromAnagasta küehniella (Zeller),Ephestia cautella (Walker),E. elutella, (Hübner),E. figulilella (Gregson), andPlodia interpunctella (Hübner) and exposed to adults of the egg parasite,Trichogramma evanescens Westwood, in a free choice experiment. Host eggs were ranked by decreasing percentages of parasitization as follows:E. elutella > E. cautella > E. figulilella > A. küehniella > P. interpunctella. Differences in percent parasitization were not significant betweenEphestia spp., butA. küehniella andP. interpunctella were parasitized significantly less often. Average percentage egg hatch after exposure toTrichogramma ranged from 5.0 to 9.3%, except forPlodia where it averaged 33.3%. It appears that inundative releases ofTrichogramma into commodity storages could play an important role in suppression of stored-product moth populations.  相似文献   

6.
An account is given of 4 new species ofMirufens Girault:M. brevifuniculata Khan & Shafee, M.albiscutellum Khan & Shafee,M. magniclavata Khan & Shafee andM. longiclavata Khan & Shafee. A key to Indian species of the genusMirufens is also provided.  相似文献   

7.
The exotic root weevil egg parasite,Tetrastichus haitiensis Gahan, imported from Puerto Rico and released in Florida between 1969 and 1971, was found established on citrus root weevil egg masses in 1978 near Oakhill, Florida. It was also recovered there from field-collected weevil egg masses from June to August 1978 and from citrus bouquets containing egg masses placed in the grove during July and August 1978. In addition, a new species ofTrichogramma was discovered. In the laboratory, this species parasitized egg masses of 4 species of weevils that attack citrus in Florida. These areDiaprepes abbreviatus (L.),Pachnaeus litus (Germar),P. opalus (Olivier) andArtipus floridanus Horn.  相似文献   

8.
In the greenhouse, rates of parasitization ofAnagasta kuehniella (Zeller) eggs byTrichogramma pretiosum (Riley) were significantly increased when treated with water extracts of the weed,Amaranthus retroflexus L.: 1) Parasitization rates appeared to be dose dependent with greatest percentage parasitization obtained fromVicia faba L. plants sprayed with 2.5 ml of the extract, 2) Parasitization rates increased with an exposure time of 24 h, and 3) Plants sprayed withA. retroflexus in mosaic patterns interspersed with 2 additional plant extracts (Chenopodium album L. andPortulaca oleracea L.) did not show a total increase of parasitization over control plants treated with water.  相似文献   

9.
Sensory receptors of the ovipositor ofTrichogramma maidis are described. Sense organs are found on the 2nd valvifers (1 type), on the tip of the 3rd valvulae (2 types) and on the 1st valvulae (4 types). The nature and possible functions of these sensilla are discussed.   相似文献   

10.
M. W. Brown 《BioControl》1984,29(3):249-265
Literature onOoencyrtus kuvanae (Howard) from throughout the world is reviewed. References from Asia, Japan, Europe, Africa, and North America, covering the years 1900–1983, are included. The information is divided into the following subject areas: taxonomy, host range, distribution and introductions, biology and life history, host suitability, behavior and spatial distribution, effectiveness, and population dynamics. Suggestions for future research are presented.  相似文献   

11.
ME, PGM and PGI electrophoretic banding patterns in 20 laboratory cultures representing 14 species ofTrichogramma were studied. Variations in PGM were found inT. exiguum, T. marylandense, andT. pretiosum. PGI also showed variation inT. exiguum, T. marylandense, T. minutum, andT. parkeri. However, ME variations were found only inT. pretiosum. Based on progeny analyses, we concluded that ME is a tetramer inTrichogramma with fast and slow alleles at a single locus, and that both PGM and PGI have a single locus and each has four alleles. PGM is a monomer, but PGI is a dimer.
Résumé Les bandes électrophorétiques de l'enzyme malique, de la P.G.M. et de la P.G.I. ont été étudiées chez 20 souches de laboratoire représentant 14 espèces deTrichogramma. Des variations de la P.G.M. ont été trouvées chezT. exiguum, T. marylandense etT. pretiosum. La. P.G.I. montre aussi des variations chezT. exiguum, T. marylandense, T. minutum etT. parkeri. Par contre, des variations de l'enzyme malique ne sont trouvées que chezT. pretiosum. En nous basant, sur l'analyse de progénitures, nous avons conclu que l'enzyme malique est un tétramère chezTrichogramma comprenant un allèle “lent” et un alléle “rapide”, à un seul locus, et que la P.G.M. et la P.G.I. ont chacune un seul locus à quatre allèles. La P.G.M. est un monomère mais la P.G.I. est un dimère.
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12.
Trichogramma brassicae Bezdenko is used throughout Europe as an effective biological control agent against the European corn borer (Ostrinia nubilalis Hübner). However, in certain climatic regions, the biological control exerted by this parasitoid is less effective. High temperatures inside the released capsules are suspected to have a negative influence on the parasitoids. To simulate these adverse conditions, we applied heat shocks (35°C and 44°C) for 6 hours to pupae ofTrichogramma brassicae at two periods: white pupae and melanized pupae. The results showed the susceptibility of both the white pupae and melanized pupae, especially at 44°C. At this temperature, the adults (G0 generation) derived from pupae treated at any age showed reduced longevity and fecundity. Moreover, those descended from treated melanized pupae showed an emergence rate lower than that of the control. These effects reduced to half and more the parasitic efficiency of the G0 generation. For the progeny (G1 generation), we observed a decrease of the female ratio: 38% for the progeny of adults derived from treated melanized pupae; 88% for the progeny of those derived from treated white pupae. In that condition, the G1 generation, almost totally male, could not have any parasitic activity.  相似文献   

13.
Inundative releases of the egg parasitoidTrichogrammatoidea cryptophlebiae Nagaraja were made againstCryptophlebia leucotreta (Meyrick) on 5 commercial citrus farms in the western Cape Province, South Africa, over 2 successive seasons. A target release volume of 80 000 parasitoids ha−1 week−1 was established for releases over 29 and 33 weeks during the 2 seasons. Total seasonal volumes reached an equivalent of 2.3 and 3.8 million parasitoids ha−1 respectively. Compared with check treatments on each farm, larval population size was reduced in the release areas by 54% in the 1st and by almost 60% in the 2nd season. Percentage crop loss was reduced by 49.4±12.4 and 61.1±8.3% respectively. Treatment effects were clearly related to increases in rate of parasitism measured in both artificially-placed and in nativeC. leucotreta egg populations. Treatment efficacy is similar to that obtained with applications of chitin synthesis inhibitors but parasitoid production costs are 30% of insecticide costs. Manual distribution of parasitoids is labour intensive, however, and further studies should investigate whether inoculative releases at higher rates per week over a shorter period, are effective.   相似文献   

14.
Two new species ofTrichogramma from the U.S.A. are described.T. parkeri sp. n., a morphologically distinct species, was reared from an egg ofHeliothis zea (Boddie), whileT. platneri sp. n. which is morphologically indistinguishable fromT. minutum Riley, was reared from eggs ofCydia pomonella (L.). Reproductive incompatibility ofT. platneri andT. minutum is discussed.  相似文献   

15.
Among 6 laboratory hosts tested, the egg-larval parasitoidChelonus blackburni Cameron completed its development in only 3;Corcyra cephalonica Stainton,Phthorimaea operculella (Zeller) andAchroia grisella (Fabricius). The parasitoid failed to develop inSpodoptera litura (Fabricius),Galleria mellonella L. andSitotroga cerealella (Olivier). The development period of the parasitoids obtained from permissive hosts correspond to the development period of their hosts. Development period ofP. operculella, A grisella andC. cephalonica were 24.7±2.0, 39.5±2.1 and 50.5±4.1 days respectively while the development period of the parasitoid reared from these hosts were 25.8±1.6, 36.4±3.5 and 42.5±3.5 days respectively. The fecundity of the parasitoids reared onA. grisella, P. operculella andC. cephalonica were 365.2±52.8, 287.9±101.9 and 248.7±50.8 respectively. The size of the parasitoids reared from the above 3 hosts also followed the similar trend. However, no significant difference was observed on the percent parasitism and the longevity of the parasitoids reared on different hosts. This study was conducted at a temperature of 24±2°C and 60±5% RH. Contribution No 46001 of Biological Control Centre (NCIPM), Bangalore.  相似文献   

16.
R. J. Dysart 《BioControl》1990,35(3):307-313
Anaphes diana (Girault) (=Patasson lameerei Debauche), a mymarid egg parasite ofSitona spp., was introduced from Europe beginning in 1976 and is now tentatively established in the United States. Techniques are described for the separation of eggs ofSitona spp. from soil, using a series of fine-mesh sieves, water, and a saturated salt solution. Data from 9 years of sampling in an alfalfa field at Newark, Del. (>19,300 host eggs extracted), showed that the mean peak density of viable overwintering eggs ofSitona hispidulus (F.) was 14.6 per 100 cm3 of 1 cm deep surface soil. At the study site,Sitona egg densities consistently increased during the fall as a result of oviposition, peaked during January and February and decreased during the spring as a result of egg hatch. Although the incidence of parasitism byA. diana remained surprisingly low (0.29%), the fact that the species was recovered during 3 years and up to 7 years after the last release, indicates that it has colonized at the Delaware release site.   相似文献   

17.
Résumé L'étude des croisements entre 2 souches de trichogrammes proches a montré que 2 espèces jumelles étaient confondues:T. evanescens Westwood etT. maidis n. sp. La première parasite surtout des œufs de lépidoptères du chou tandis que le deuxième parasite les œufs d'Ostrinia nubilalis Hubn. (Lep.: Pyralidae). T. evanescens est redécrit etT. maidis n. sp. décrit, les principales différences portant sur l'échancrure de la lame dorsale des génitalia males et sur le nombre de soies des antennes des 2 sexes.
Summary The crossing study between 2 very similars strains ofTrichogramma indicates that 2 sibling species were confused:T. evanescens Westwood andT. maidis n. sp. The first parasitizes mainly Lepidopterous eggs on cabbage while the second parasitizesOstrinia nubilalis Hubn. (Lep.: Pyralidae) eggs.T. evanescens is redescribed andT. maidis n. sp. described. The chief differences relate to the notch of the dorsal expansion of gonobase in the male genitalia and to the number of antennal bristles in the two sexes.


Avec la collaboration technique deM. Babault et deJeannine Pizzol.  相似文献   

18.
Progeny production ofBiosteres (Opius) longicaudatus Ashmead, a larvalpupal parasite of the Caribbean fruit fly,Anastrepha suspensa (Loew) was affected by host availability, previous ovipositional experience, and parasite density and age. Parasitization rates were evaluated in 24.5 cm3 ovipositional cages at parasite densities of 25, 125, and 250 male-female pairs by exposingB. longicaudatus adults to (a) 500A. suspensa larvae for a 24 h period or (b)ad libitum host larvae for each of the 14 days following eclosion. The mean numbers of parasite progeny produced at the 25, 125, and 250 densities were 1076, 1896, and 2038, respectively. The number of progeny produced per surviving female parasite was inversely proportional to the adult parasite density and relatively more female progeny were produced as the adult parasites aged. Host mortality was significantly higher among parasitized larvae. Maximum rearing efficiency was achieved at the 125 density.  相似文献   

19.
Résumé Euselasia eucerus Hewitson est un ravageur de l'eucalyptus au Brésil. Certains aspects de sa biologie et de son éthologie ont été abordés sur le terrain et au laboratoire — Une analyse de la distribution verticale des chrysalides et des pontes montre que 80% de la nymphose se fait dans le sous-bois (jusqu'à 1 m de hauteur) et que les 20% restants se fait sur les eucalyptus (de 14 m de hauteur en moyenne). De ces 20%, 90% se fixent jusqu'à 6 m de hauteur. Quant à la ponte, elle se fait sur les feuilles d'eucalyptus, avec 75% entre 2 et 8 m. 31,6% des œufs observés entre 0 et 10 m sont parasités parTrichogramma sp., ce pourcentage diminuant à 12% au-dessus de 10 m. Ce niveau élevé de parasitisme dans la nature nous suggère l'utilisation du trichogramme pour combattre ce défoliateur.
Summary Some biological and ecological aspects ofEuselasia eucerus Hewitson, an eucalyptus pest in Brazil, under field and laboratory conditions are presented. The study of its eggs and pupae revelaed that 80% of pupation occur in the undergrowth (up to 1 m high) and 20% in the eucalyptus (14 m high), 90% of which occurred up to a height of 6 m. Eggs are laid only on the eucalyptus leaf, and most or them (75%) are found between the heights of 2 and 8 m. Between 0 and 10 m, 31.6% of the eggs were parasited byTrichogramma sp., and above 10 m the parasitism lowered to 12%. Such a high degree of parasitism in natural conditions suggests the utilisation ofTrichogramma to combat that pest.
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20.
Biological studies withChrysocharis parksi Crawford, a parasite of agromyzid leafminers, were conducted.C. parksi successfully parasitized the following species in the genusLiriomyza Mik.,L. huidobrensis (Blanchard),L. sativae Blanchard,L. trifolii (Burgess), andL. trifoliearum Spencer. Successful parasite development was recorded from 8 plant families and 16 genera. Host plants which were suitable for leafminer development to the adult stage were also suitable for parasite development. Mean immature developmental period (egg to adult, usingL. trifolii as the host) at 21.1°, 26.7°, and 32.2° C was (for both sexes) 23, 14, and 14 days, respectively. Longevity of females provided only water was inversely related to temperature; significantly longer survival occurred at 21.1° C (5.0 days) compared to 26.7° C and 32.2° C (3.2 and 2.1 days, respectively). The addition of honey to the diet significantly improved longevity of both sexes at all temperatures. Adult female parasites which were provided an average of 33.0L. trifolii larvae per day produced an average of 135 offspring at a constant 26.7° C.C. parksi host-fed on ca. 3.7 leafminer larvae per day over an 11-day adult lifespan.   相似文献   

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