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2. Abundance and host associations of parasitoids attacking frugivorous drosophilids on Iriomote-jima, a subtropical island of Japan
- Creator:
- Novkovic, Biljana, Oikawa, Ayako, Murata, Yusuke, Mitsui, Hideyuki, and Kimura, Masahito T.
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Hymenoptera, Braconidae, Asobara, Figitidae, Leptopilina, Diptera, Drosophilidae, Drosophila, parasitoid, host association, resistance, virulence, 2, and 59
- Language:
- English
- Description:
- To understand the factors governing the diversity, abundance and host associations of parasitoids attacking frugivorous drosophilid flies on Iriomote-jima, a subtropical island of Japan, we monitored parasitism on several occasions over the period 2003–2009. Fifteen drosophilid and 12 parasitoid species were recorded. Three species of Drosophila, D. bipectinata, D. albomicans and D. takahashii, bred abundantly in banana baits, though their abundance varied between years and seasons. Frequent parasitoid species were Asobara japonica, A. pleuralis (Braconidae), Leptopilina ryukyuensis and L. pacifica (Figitidae). L. victoriae was recorded only in December 2003. In addition, host acceptance and host suitability of the four most frequently recorded parasitoid species were studied in the laboratory. Most parasitoid and drosophilid species showed species-specific associations with more than one antagonist species, suggesting that they have been subjected to complex coevolutionary interactions. In addition, host range of most of the parasitoid species included one of the three major Drosophila species, suggesting that the abundance of potential hosts is one of the factors determining the evolution of parasitoid host use., Biljan Novkovic ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3. Ant diversity (Hymenoptera: Formicidae) and predation by ants on the different stages of the sugarcane borer life cycle Diatraea saccharalis (Lepidoptera: Crambidae)
- Creator:
- Oliveira, R.D.F, Almeida, L.C.D., Souza, D.R.D., Munhae, C.B., Bueno, O.C., and Morini, M.S.C
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Hymenoptera, Formicidae, biological control, Diatraea saccharalis, mechanical cultivation, 2, and 59
- Language:
- English
- Description:
- The sugarcane borer Diatraea saccharalis is an important pest of sugarcane and ants are one of its main predators. The practice of burning sugarcane straw in situ after harvest has been gradually replaced in Brazil by other practices. However, it is unknown whether ants can control the abundance of this borer in the presence of straw. In this study, we assessed the diversity and species composition of ants attacking different stages of the pest’s life cycle. Specifically, we asked whether the species richness and abundance of ants varies during the course of day and a year. We established one-hectare plots at random locations in a sugarcane plantation. Once a month, we collected 20 samples of each stage of the D. saccharalis life cycle and randomly distributed these samples as bait on plants spaced 20 m apart within a plot. Ants were collected daily in the morning and afternoon over a period of 12 months. We identified several aspects of ant feeding behaviour that may affect their biological control of the borer: (1) the greatest number of ants were collected from baits consisting of the immature stages of the sugarcane borer, (2) ants were most active in the morning and (3) their activity varied from month to month. Solenopsis saevissima and morphotypes of Crematogaster sp.7 and Pheidole sp.35 are potentially important predators of borers in sugarcane crops in which the straw is not burnt., Roseli de Fatima de Oliveira ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
4. Biology of the conifer needle scale, Nuculaspis abietis (Hemiptera: Diaspididae), in northern Iran and parasitism by Aspidiotiphagus citrinus (Hymenoptera: Aphelinidae)
- Creator:
- Rasekh, Arash, Michaud, J. P., and Varandi, Hassan Barimani
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, Írán, Iran, Nuculaspis abietis, Diaspididae, Hemiptera, Aspidiotiphagus citrinus, Aphelinidae, Hymenoptera, Picea abies, Norway spruce, development, host range, parasitism, 2, and 59
- Language:
- English
- Description:
- The conifer needle scale, Nuculaspis abietis (Schrank) emerged as an important pest of conifers in the Kelardasht region of Mazandaran province, Iran, in the late 1990's. This pest feeds on conifer needles and twigs causing needle drop and branch desiccation. Its discovery in Kelardasht in Mazandaran Province necessitated a local quarantine of conifers in the genera Picea, Abies, and Pinus. We studied the life history and ecology of this scale on Norway spruce, Picea abies, under laboratory and natural field conditions. The complete life cycle of females required 206.4 ± 5.7 days in the laboratory (25 ± 1°C, 65-75% RH, 14L : 10D) and 315.7 ± 9.3 days under field conditions. In Kelardasht, numbers of adult males and females peaked in mid-June and early May, respectively, and numbers of first and second instar nymphs in mid-July and early September. Lifetime fecundity was estimated to be 57.3 ± 5.1 eggs and 54.0 ± 4.4 nymphs per female under laboratory conditions. The sex ratio ranged from 59% female for second instar nymphs to 71% female for adults. Aspidiotiphagus citrinus (Crawford) (Hymenoptera: Aphelinidae) was found naturally parasitizing the scale and overwintering in the larval stage on second instar nymphs. First generation adult wasps emerged in spring from overwintered second instar nymphs to parasitize 64.75% of first instar scales. Second generation wasps emerged from early September to mid-October and parasitized 19.75% of second instar scales, for a cumulative parasitism rate of 84.5%. and Arash RASEKH, J.P. MICHAUD, Hassan BARIMANI VARANDI.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
5. Bumblebee (Hymenoptera: Apidae) sample storage for a posteriori molecular studies: interactions between sample storage and DNA-extraction techniques
- Creator:
- Moreira, António S., Horgan, Finbarr G., Murray, Tomás E., and Kakouli-Duarte, Thomas
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Hymenoptera, Apidae, Bombus terrestris, acetone, commercial kit, DNA quality, entomological pins, freezing, phenol-extraction, 2, and 59
- Language:
- English
- Description:
- A global decline in pollinator abundance and diversity has demanded increased research attention to the ecology and genetics of bumblebees. However, as progressively more restrictions are placed on sampling for insects, researchers are increasingly obliged to use archival specimens collected for purposes other than genetic analyses. In this study we assessed the suitability, for population genetic studies, of popular, low-cost methods for preservation and storage of bumblebee specimens. Specimens of Bombus terrestris L. were held under six storage regimes for up to two years. DNA was extracted from the samples using three extraction protocols and the quality of the DNA was examined using PCR amplification of a mitochondrial and a nuclear gene. All extraction and storage methods provided sufficient DNA for successful PCR amplification. However, samples preserved in acetone or at freezing temperatures yielded the highest DNA concentrations. DNA yields from pinned specimens at room temperature declined over time, particularly when using standard extraction techniques. DNA concentrations were significantly lower from specimens preserved in 70% ethanol compared to all other extraction techniques and declined linearly over the two years of storage. These results indicate that two of the most popular insect storage methods (pinning and storage in ethanol) should be avoided for the long-term preservation of genetic material for future studies. We suggest that optimal insect preservation methods should be incorporated into research protocols in order to best capitalise on limited collection opportunities., António S. Moreira ... []., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
6. Causes of polymorphic melanism and its thermoregulatory function in a parasitoid wasp Meteorus pulchricornis (Hymenoptera: Braconidae)
- Creator:
- Abe, Yosuke, Nishimura, Takuma, and Maeto, Kaoru
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, entomology, Hymenoptera, Braconidae, Meteorus pulchricornis, parasitic wasp, body colour variation, thermal melanism hypothesis, reaction norm, solar radiation, body temperature, flight activity, 2, and 59
- Language:
- English
- Description:
- We investigated the variation in body colour and its thermoregulatory function in Meteorus pulchricornis (Wesmael) (Hymenoptera: Braconidae), a parasitoid wasp of Spodoptera and other free-living lepidopteran larvae. We show that the body colour of adult wasps darkens when cocoons are kept at low temperatures. The range in the variation in colour, however, differs for different parts of the body and among uniparental (thelytokous) strains. This melanism enables these wasps to attain a body temperature in sunshine up to 2°C. Moreover, this small gain in body temperature can markedly increase the flight activity of wasps at low ambient temperatures. We conclude that the variation in body colour that resulted from rearing the cocoons at different temperatures enable the wasps to adapt to changing thermal environments. The ecological significance of the difference in the degree of melanism of the different strains is discussed., Yosuke Abe, Takuma Nishimura, Kaoru Maeto., and Seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
7. Cold storage affects mortality, body mass, lifespan, reproduction and flight capacity of Praon volucre (Hymenoptera: Braconidae)
- Creator:
- Lins Jr, Juracy Caldeira, Bueno, Vanda Helena Paes, Sidney, Livia Alvarenga, Silva, Diego Bastos, Sampaio, Marcus Vinicius, Pereira, Janser Moura, Nomeliny, Quintiliano Siqueira Schroden, and Van Lenteren, Joop C.
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Hymenoptera, Braconidae, Praon volucre, biological control, storage, Macrosiphum euphorbiae, 2, and 59
- Language:
- English
- Description:
- The possibility of storing natural enemies at low temperatures is important for the mass production of biological control agents. We evaluated the effect of different periods of cold storage on immature mortality, mummy body mass, lifespan, reproduction and flight capacity of the parasitoid Praon volucre (Haliday). One-day-old mummies of the aphid Macrosiphum euphorbiae (Thomas) containing pre-pupae of P. volucre were stored in a climatic chamber at 5°C and 70 ± 10% RH in the dark for different periods of time (5, 10, 15 and 20 days). The control consisted of mummies kept at 22 ± 1°C, 70 ± 10% RH and a 12 h photophase. Percentage adult emergence, mummy body mass, flight capacity and number of eggs in the ovarioles of P. volucre females decreased with increase in the period of storage, while the longevity of females was only slightly affected. Fat content of mummies, percentage of parasitized aphids and survival of progeny to emergence decreased with increase in the period of storage. Storage of P. volucre pre-pupae for up to 5 days at 5°C did not affect any of the above mentioned parameters. The fact that P. volucre pre-pupae can be stored for 5 days without loss of quality and for 10 days with only a slight loss facilitates the planning of mass production and shipment., Juracy Caldeira Lins, Jr. ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
8. Comparative analysis of maternal and grand-maternal photoperiodic responses of Trichogramma species (Hymenoptera: Trichogrammatidae)
- Creator:
- Voinovich, Natalia D., Vaghina, Nina P., and Reznik, Sergey Ya.
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Hymenoptera, Trichogrammatidae, Trichogramma, diapause, photoperiod, temperature, maternal effect, grand-maternal effect, comulative photoperiodic effect, 2, and 59
- Language:
- English
- Description:
- 1_Maternal and grand-maternal photoperiodic responses of Trichogramma buesi, T. embryophagum, T. evanescens, T. piceum, T. principium, and T. telengai were investigated in laboratory conditions. During the experiment, grand-maternal and maternal generations developed at 20°C and one of the 4 photoperiodic regimes: L : D = 12 : 12, 14 : 10, 16 : 8, and 18 : 6 (in total, 16 combinations) while the progeny developed at L : D = 12 : 12 and one of the 3 thermal regimes: 13, 14, and 15°C. The proportion of diapausing individuals in the progeny of all the studied species was significantly dependent on the direct influence of temperature and on the maternal photoperiodic response. The influence of the photoperiodic conditions during development of the grand-maternal generation was statistically significant in 5 of the 6 studied species, being relatively weak in T. embryophagum and T. telengai, whose geographical ranges extend up to north-western regions of Europe (possibly, these wasps enter diapause so early that the grand-mothers of the diapausing generation develop under long day conditions). Comparative analysis showed that the thresholds of the maternal and grand-maternal photoperiodic responses coincided or almost coincided. The grand-maternal effect was stronger in the progeny of maternal females which developed under short day conditions than in those that developed under long day conditions. This pattern of interaction probably synchronizes the life cycle with seasonal changes because diapause is induced under decreasing day length and thus mothers of diapausing individuals develop at shorter daylength than do grand-mothers., 2_We conclude that the grand-maternal and the maternal effects on Trichogramma progeny diapause are based on one and the same photoperiodic response. In nature, the grand-maternal effect increases the proportion of diapausing individuals in the progeny of females which have developed under short day conditions during two generations, thus achieving a "cumulative" photoperiodic effect., Natalia D. Voinovich, Nina P. Vaghina, Sergey Ya. Reznik., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
9. Cytogenetic characterization of Diachasmimorpha longicaudata (Hymenoptera: Braconidae), a parasitoid wasp used as a biological control agent
- Creator:
- Carabajal Paladino, Leonela, Papeschi, Alba, Lanzavecchia, Silvia, Cladera, Jorge, and Bressa, María José
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Hymenoptera, Braconidae, Diachasmimorpha longicaudata, karyotype, C-banding, heterochromatin, Ag-NOR, FISH, rDNA, 2, and 59
- Language:
- English
- Description:
- Diachasmimorpha longicaudata (Hymenoptera: Braconidae) is a parasitoid wasp widely used in the biological control of fruit flies. In this paper, we present a detailed analysis of the karyotype of this species based on the results of classical and molecular cytogenetic techniques. The cytogenetic analysis confirmed the male and female chromosome numbers previously reported (n = 20, 2n = 40). The entire short arm of most chromosomes is made up of a large constitutive heterochromatic segment. The high heterochromatin content differentiates D. longicaudata from other braconid species. Fluorescence in situ hybridization (FISH) using autologous 18S rDNA probes revealed six clusters of rDNA, i.e. six nucleolar organizer regions (NORs), in the heterochromatic short arms of different chromosomes in the haploid male karyotype. This number is exceptionally high for Hymenoptera, which usually have two NORs in the diploid complement. It is noteworthy that these rDNA-FISH experiments represent the first use of this technique on a braconid species using autologous probes. Since Ag-NOR-bands were coincident with C-positive bands on metaphase chromosomes, it was not possible to identify active nucleoli. The physical characteristics of the D. longicaudata karyotype, especially the content and distribution of heterochromatin and the number and location of rDNA clusters, contribute to a better understanding of the structure and organization of braconid chromosomes and provide a basis for genomic and evolutionary studies., Leonela Carabajal Paladino ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
10. Does the decline of red wood ants after clear-cutting favour epigeic arthropods?
- Creator:
- Żmihorski, Michał
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, Hymenoptera, Formica, predation, competition, forest management, clear-cuts, intra-guild predation, 2, and 59
- Language:
- English
- Description:
- In forest ecosystems in the temperate and boreal zones in Europe, red wood ants (RWA, Formica rufa group) have a significant affect as predators and competitors in communities of ground-dwelling arthropods. Therefore, the spatiotemporal distribution and abundance of RWA affect the distribution of many other species. The hypothesis that a reduction in the abundance of RWA in clear-cut areas enables other arthropods to increase in abundance was tested. The study was conducted in NW Poland in 2007 and 2008. A total of 276 1×1 m plots were sampled and 1,696 individuals recorded. The probability of the occurrence of RWA decreased significantly towards the center of clear-cut areas and increased with increasing plant cover. The frequency of Lasius platythorax, Formica fusca and spiders in the plots significantly increased towards the edge of a clear-cut area. Moreover, the occurrence of L. platythorax was negatively associated with the presence of RWA, while that of the Myrmica species was positively associated. The effect of the distance to the edge of a clear-cut area seems to be much more pronounced than the effect of RWA. This suggests that the arthropods studied prefer habitats close to the edge that are utilized by RWA than RWA-free sites located in the centre of clear-cut areas. and Michal Zmihorski.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
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