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2. Chemical cues mediating aphid location by natural enemies
- Creator:
- Michaud, J.P., Hatano, Eduard, Kunert, Grit, and Weisser , W.
- Type:
- article, model:article, and TEXT
- Subject:
- Aphid, natural enemies, host selection, semiochemicals, and infochemical
- Language:
- English
- Description:
- There is increasing evidence that chemical cues play a pivotal role in host selection by the natural enemies of aphids. We use Vinson's (1976) division of the host selection process into habitat location, host location and host acceptance for both parasitoids and predators and review what is known about the role of semiochemicals in aphid selection by natural enemies. For habitat location (i.e. detection of the host plant), volatiles emitted by plants after aphid attack have been described for a number of plant-aphid interactions. These synomones indicate not only the presence of an aphid host plant to the predator or parasitoid, but also the presence of aphids. Volatiles emitted from undamaged host plants are often attractive to aphid parasitoids, but less so for predators. Host location by the natural enemy on the food plant is guided by semiochemicals that mostly originate from the aphids, in particular aphid alarm pheromone, honeydew, or the smell of the aphid itself. Host acceptance is guided by contact chemicals for both predators and parasitoids. In parasitoids, host recognition may be based on visual cues or on contact chemicals on the aphid's cuticle, whereas host acceptance is ultimately based on as yet unknown substances within the aphid's hemolymph. While it appears that many predators and parasitoids are attracted to the same semiochemicals, synergistic and antagonistic interactions among chemical substances have only rarely been investigated. More research into model systems is needed, not only to identify important semiochemicals, but also to determine their range of attraction. Recent progress in the development of analytical techniques has created new opportunities to improve our understanding of the chemical ecology of aphid-natural enemy interactions in the coming years.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3. Dinocampus coccinellae (Hymenoptera: Braconidae) utilizes both Coccinellini and Chilocorini (Coleoptera: Coccinellidae: Coccinellinae) as hosts in Kashmir Himalayas
- Creator:
- Maqbool, Amir, Ahmed, Imtiaz, Kiełtyk, Piotr, and Ceryngier, Piotr
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- blanokřídlí, lumčíkovití, brouci, slunéčkovití, Hymenoptera, Braconidae, beetles, Coccinellidae, Dinocampus coccinellae, Coleoptera, Oenopia conglobata, Priscibrumus uropygialis, parasitoid, host selection, host suitability, 2, and 59
- Language:
- English
- Description:
- Dinocampus coccinellae is a parasitoid wasp usually parasitizing ladybird beetles of the tribe Coccinellini. A field survey conducted between March and November 2016 revealed three hosts of this parasitoid in the Srinagar district of the Indian state of Jammu and Kashmir: two members of the Coccinellini (Oenopia conglobata and Coccinella undecimpunctata) and one of the Chilocorini (Priscibrumus uropygialis). Proportion of the latter (atypical) host that were parasitized was 0.09 and intermediate between that recorded for C. undecimpunctata (0.06) and O. conglobata (0.14). A series of laboratory experiments revealed that while a member of Coccinellini (O. conglobata) was more often attacked by D. coccinellae than a member of Chilocorini (P. uropygialis), the proportions of each species from which parasitoids emerged did not differ significantly. There were no significant differences between D. coccinellae females bred from O. conglobata and P. uropygialis, with respect to selection of the two host species and their suitability for the development of the parasitoid. However, members of the Chilocorini other than P. uropygialis (Chilocorus infernalis and Simmondsius pakistanensis) were rarely attacked by D. coccinellae and parasitoid larvae did not emerge from any of those attacked. The results of our experiments indicate that in Kashmir Himalayas D. coccinellae is adapted to parasitize hosts belonging to both Coccinellini and Chilocorini., Amir Maqbool, Imtiaz Ahmed, Piotr Kiełtyk, Piotr Ceryngier., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
4. Effect of female size on host selection by a koinobiont insect parasitoid (Hymenoptera: Braconidae: Aphidiinae)
- Creator:
- Lykouressis, Dionyssios, Garantonakis, Nikolaos, Perdikis, Dionyssios, Fantinou, Argyro, and Mauromoustakos, Andronikos
- Type:
- article, model:article, and TEXT
- Subject:
- Hymenoptera, Braconidae, Aphidius colemani, Hemiptera, Aphis gossypii, Myzus persicae, aphid, body size, and host selection
- Language:
- English
- Description:
- Body size is a main fitness component of insect parasitoids. We assessed the potential influence of maternal size of the parasitoid wasp Aphidius colemani Viereck (Hymenoptera: Braconidae: Aphidiinae) on its ability to parasitize the different instars of Aphis gossypii Glover (Hemiptera: Aphididae) on eggplant and cucumber. In the experiments "small" vs "large" parasitoid females were used. Females oviposited in all instars but more of the smaller hosts were parasitized. Host selection was affected by female size and the larger hosts were more frequently mummified by the large than the small females. Thus, parasitoid female size influenced host selection. This could affect the potential of the parasitoid to exploit populations of aphids that differ in their size structure. The importance of these results in terms of the ecological adaptations of the parasitoid and their implication for biological control are discussed.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
5. Effect of host egg age on preference, development and arrestment of Telenomus remus (Hymenoptera: Scelionidae)
- Creator:
- Penafor, Maria Fernanda Gomes Villalba, Sarmento, Mariana Montagne de Moraes, Bezerra da Silva, Cherre Sade, Werneburg, Andrea Graf, and Bento, José Maurício Simoes
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Hymenoptera, Scelionidae, Telenomus remus, egg parasitoid, Noctuidae, Spodoptera frugiperda, fall armyworm, host selection, egg age discrimination, behaviour, developmental biology, 2, and 59
- Language:
- English
- Description:
- Age of host eggs can be a limiting factor for egg parasitoids. It is expected that old eggs are less preferred by egg parasitoids, which can discriminate between eggs of different ages by using chemical cues. The objective of this study was to determine the preference, development and arrestment of Telenomus remus Nixon (Hymenoptera: Scelionidae) parasitizing Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) eggs of different ages. This egg parasitoid preferred to parasitize 1- and 2-day-old eggs rather than 3-day-old eggs in choice and no-choice assays. However, although the percentage emergence of parasitoids is significantly lower from 2- and 3-day-old eggs, the sex ratio and developmental time are unaffected. Parasitoids spent longer searching substrates impregnated with extracts of 1- and 2-day old eggs than 3-day-old eggs. Our results reveal that T. remus is able to distinguish the most suitable (1-day-old) from the least suitable (3-day-old) host eggs, but unable to recognize the unsuitability of intermediate aged eggs. Egg arrestants may be responsible for the preference of T. remus for ovipositing in 1- and 2-day old eggs., Maria Fernanda Gomes Villalba Penaflor ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
6. Kairomone involvement in the host specificity of the egg parasitoid Trissolcus basalis (Hymenoptera: Scelionidae)
- Creator:
- Salerno, Gianandrea, Conti, Eric, Peri, Ezio, Colazza, Stefano, and Bin, Ferdinando
- Type:
- article, model:article, and TEXT
- Subject:
- Scelionidae, Trissolcus basalis, egg parasitoid, Pentatomidae, kairomone, host selection, and host specificity
- Language:
- English
- Description:
- This paper reports the results of a comparative laboratory analysis of the behavioural responses of the egg parasitoid Trissolcus basalis (Wollaston) (Hymenoptera: Scelionidae) to semiochemical cues from four species of pentatomid bugs, Nezara viridula (L.), Eurydema ventrale Klt., Murgantia histrionica Hahn. and Graphosoma semipunctatum F. (Heteroptera: Pentatomidae). In a Y-tube olfactometer, T. basalis was attracted by volatile chemicals from N. viridula, but not from other pentatomid species. In an open arena, the parasitoid reacted to chemical trails left on filter paper by all the species but most intensely to those left by N. viridula. However, upon encountering pentatomid eggs, T. basalis examined more intensely and probed more frequently the eggs of G. semipunctatum than those of the other species. The parasitoid only parasitized and emerged from eggs of G. semipunctatum and N. viridula; those of the other species were unsuitable. Therefore N. viridula is semiochemically confirmed to be a coevolved host (old association) of T. basalis, whereas G. semipunctatum may be a potential non-coevolved host (new association). The utility of these tests for defining a parasitoids' host specificity and in assessing the risk of non-target effects in biological control is discussed.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
7. Maladaptive host choice by an alien leaf miner Phyllonorycter leucographella (Lepidoptera: Gracillariidae) has the potential to limit its invasiveness
- Creator:
- Walczak, Urszula, Bogdziewicz, Michał, Żytkowiak, Roma, Karolewski, Piotr, and Baraniak, Edward
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- motýli, vzpřímenkovití, butterflies, Gracillariidae, Lepidoptera, Phyllonorycter leucographella, invasive species, alien leaf miner, host selection, specific leaf area, infestation rate, insect development, 2, and 59
- Language:
- English
- Description:
- Alien phytophagous insects are often introduced along with their host plants, creating opportunities for troublesome invasions. Yet, not all of them are able to successfully colonize novel host plants. In this study, we investigated host selection by the alien leaf miner Phyllonorycter leucographella (Zeller, 1850) on both its original host and novel host plants in the insect's alien range. We predicted that this insect's percentage infestation of the original host would be positively related to its specific leaf area (SLA), because high-SLA leaves are nutritious and have thin cuticles, traits related to high offspring developmental success. We further hypothesized that this host selection process would apply in the selection of novel host plants. Our results show that this leaf miner selects leaves of its original host plant, Pyracantha coccinea, according to their SLA values. The SLA value was also positively related to the probability of P. leucographella infesting and successfully developing on novel host plants. The selection of high-SLA plants by the moth leads to a high developmental success on novel host plants in the first (summer) generation, but it is likely to be maladaptive in the second (overwintering) generation, because in temperate Europe, high SLA values are associated with deciduous plants that shed their leaves in autumn. It is likely that the apparent maladaptive selection of novel host plants by P. leucographella reduces the invasiveness of this pest by preventing its establishment on native plants., Urszula Walczak, Michał Bogdziewicz, Roma Żytkowiak, Piotr Karolewski, Edward Baraniak., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public