The influence of host food plants on host recognition by four aphidiine parasitoids (Hymenoptera: Braconidae)

1991 ◽  
Vol 81 (4) ◽  
pp. 449-453 ◽  
Author(s):  
W. Powell ◽  
A.F. Wright
Keyword(s):  
Attack Rate ◽  
Aphid Species ◽  
Food Plants ◽  
Host Recognition ◽  
Aphidius Ervi ◽  
Plant Leaves ◽  
Host Preferences ◽  
Aphid Parasitoids ◽  
Laboratory Populations

AbstractThe attack rate of four parasitoids against different aphid species was investigated in the absence and presence of leaves from aphid food plants. The parasitoids used, Aphidius ervi Haliday, A. rhopalosiphi De Stefani, A. picipes (Nees) and Ephedrus plagiator Nees, varied in the extent of their host ranges. The presence of plant leaves significantly influenced the attack rate of A. ervi and A. rhopalosiphi, the two parasitoids with the most restricted host ranges, but did not appear to affect attack rates by the more polyphagous A. picipes and E. plagiator. Consideration of these results together with those from previous studies on the host preferences of laboratory populations of A. ervi and A. rhopalosiphi leads to the conclusion that genotype is probably determining the responses of individual parasitoids to semiochemicals involved in host recognition. It is proposed that field populations of oligophagous aphid parasitoids consist of a mixture of specialist and generalist individuals.

scholarly journals Rapid responses of winter aphid-parasitoid communities to climate warming

2018 ◽  
Author(s):  
K. Tougeron ◽  
M. Damien ◽  
C. Le Lann ◽  
J. Brodeur ◽  
J. van Baaren
Keyword(s):  
Aphid Species ◽  
Aphidius Ervi ◽  
Parasitoid Species ◽  
Metopolophium Dirhodum ◽  
Aphid Parasitoid ◽  
Rapid Responses ◽  
Aphid Parasitoids ◽  
Change Context ◽  
Cereal Fields ◽  
Trophic Webs

AbstractConsequences of environmental fluctuations, including those associated with climate changes, can have a knock-on effect from individual to community scale. In particular, changes in species seasonal phenology can modify the structure and composition of communities, with potential consequences on their functioning and the provision of ecosystem services. In mild climate areas, aphids can be present in cereal fields throughout the winter, which allows aphid parasitoids to remain active. Using a nine-year dataset of aphid-parasitoid winter trophic webs in cereal fields of Western France, we report that the community structure and composition that prevailed before 2011 have recently shifted toward a more diversified community, with the presence of two new braconid parasitoid species (Aphidius ervi and Aphidius avenae), a few hyperparasitoid species and one aphid species (Metopolophium dirhodum). Increases in minimal winter temperatures and the frequency of frost events across the years partially explain observed community changes. Strong bottom-up effects from the relative abundances of aphid species also determine the relative abundance of parasitoid species each winter. Strong compartmentalization in parasitoid preference for host is reported. We suggest the recent modifications in parasitoid community composition to be linked to shifts in diapause expression (reduction or arrest of the use of winter diapause) and to host availability throughout the year. We highlight the implications for natural biological control in cereal fields. Perspectives are proposed to predict the composition of future host-parasitoid communities in the climate change context.

Host recognition and acceptance behaviour in two aphid parasitoid species: Aphidius ervi and Aphidius microlophii (Hymenoptera: Braconidae)

1994 ◽  
Vol 84 (1) ◽  
pp. 57-64 ◽  
Author(s):  
F. Pennacchio ◽  
M.C. Digilio ◽  
E. Tremblay ◽  
A. Tranfaglia
Keyword(s):  
Acyrthosiphon Pisum ◽  
Selection Process ◽  
Host Choice ◽  
Aphid Species ◽  
Host Recognition ◽  
Aphidius Ervi ◽  
Aphid Parasitoid ◽  
Host Aphid ◽  
Close Range

AbstractThe host preference and acceptance behaviour of populations of Aphidius ervi Haliday and A. microlophii Pennacchio & Tremblay from southern Italy was investigated. In no host-choice conditions, A. ervi females showed significantly higher attack and oviposition rates on the natural host Acyrthosiphon pisum (Harris) than on the non-host aphid Microlophium carnosum (Buckton)(Homoptera: Aphididae). In contrast, A. microlophii, which specifically parasitizes M. carnosum in the field, attacked both aphid species. However, dissections showed that oviposition of A. microlophii occurred only in a few of the attacked Acyrthosiphon pisum and was significantly less frequent than in M. carnosum. These results were confirmed in experimental host-choice conditions, suggesting that Aphidius microlophii oviposition is possibly regulated by a host haemolymphatic kairomone. Hybrids obtained by crossing A. ervi females with A. microlophii males attacked and oviposited in both aphid species, suggesting that these behavioural events have a strong genetic basis. The oviposition into host or non-host aphids did not elicit an immune defence reaction. The presence of the host's food-plant had no evident close-range effects on parasitoid attack and oviposition in non-host aphids. Aphidius microlophii reared on the non-host aphid Acyrthosiphon pisum produced a significant higher number of mummies after a few generations, suggesting a possible role of larval and early adult conditioning in the host selection process. These results, together with those from previous studies, suggest that Aphidius ervi is best considered as a complex of differentiated populations, characterized by a varying degree of genetic divergence.

scholarly journals Fungal grass endophytes, grass cultivars, nitrogen deposition and the association with colonising insects

2007 ◽  
Vol 13 ◽  
pp. 53-57
Author(s):  
J. Krauss ◽  
S.A. Härri ◽  
L. Bush ◽  
S.A. Power ◽  
C.B. Müller
Keyword(s):  
Field Experiment ◽  
Nitrogen Deposition ◽  
Fungal Endophytes ◽  
Nitrogen Addition ◽  
Aphid Species ◽  
Specific Response ◽  
Cereal Aphid ◽  
Pasture Grasses ◽  
Aphid Parasitoids ◽  
Endophyte Infection

Fungal endophytes associated with pasture grasses can have community-wide effects on insect consumers. Here we asked the question to what degree endophyte infection, simulated nitrogen deposition and grass cultivar influence the abundance of colonising herbivores and their natural enemies. In a fully randomised field experiment, consisting of four Lolium perenne monocultures of known endophyte infection status and a nitrogen addition treatment, we determined the abundance of colonising aphids, their parasitoids and predators, and other grass herbivores. The three colonising cereal aphid species did not respond to endophyte infection, possibly because peramine concentrations were relatively low (3.9 μg/g). There was a significant interaction between nitrogen addition and plant cultivar on the abundance of Sitobion avenae, suggesting a cultivar-specific response to nitrogen addition. Aphid predators were affected by an interaction between endophyte and plant cultivar, but abundance of aphid parasitoids and other grass herbivores was not affected by any treatment. The fungus Claviceps purpurea naturally infected our experimental plants and infection rates differed among cultivars and were more likely to occur on endophyte-infected plants, in particular on wild-type Samson. We conclude that strong effects of endophytes on insect abundance may not occur in systems built upon L. perenne because overall peramine levels rarely reach threshold levels for insect toxicity. Keywords: fungal endosymbionts, multitrophic interactions, field experiment, insect food webs, alkaloids

scholarly journals Emergence sexual maturation and oviposition of Aphidius ervi (Hymenoptera Aphidiidae)

2004 ◽  
Vol 57 ◽  
pp. 214-220 ◽  
Author(s):  
X.Z. He ◽  
Q. Wang ◽  
D.A.J. Teulon
Keyword(s):  
Biological Control ◽  
Life Cycle ◽  
Sexual Maturation ◽  
Acyrthosiphon Pisum ◽  
Aphid Species ◽  
Pea Aphid ◽  
Aphidius Ervi ◽  
Oviposition Period ◽  
Courtship Display ◽  
Dark Conditions

Aphidius ervi Haliday is an important parasitoid of several aphid species and information is needed for the development of massrearing techniques and better understanding of biological control ecology The emergence sexual maturation and oviposition of A ervi on pea aphid Acyrthosiphon pisum (Harris) was studied in the laboratory at 201deg;C and 6070 RH with 168 h lightdark About 95 of parasitoids emerged during the photophase Females needed a significantly longer time than males to complete their life cycle Newly emerged males were able to perform their courtship display but failed to mate until they were 4 h old; newly emerged females were able to respond to males courtship display and mate Females attacked aphids in both light and dark conditions The number of eggs laid and parasitism (number of aphids parasitised) per oviposition bout (2 h oviposition period) were significantly greater in the photophase than in the scotophase

scholarly journals Expression differences in Aphidius ervi (Hymenoptera: Braconidae) females reared on different aphid host species

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3640 ◽  
Author(s):  
Gabriel I. Ballesteros ◽  
Jürgen Gadau ◽  
Fabrice Legeai ◽  
Angelica Gonzalez-Gonzalez ◽  
Blas Lavandero ◽  
...  
Keyword(s):  
Host Plant ◽  
Differentially Expressed Genes ◽  
Host Species ◽  
Host Plants ◽  
Molecular Mechanisms ◽  
Aphid Species ◽  
Differentially Expressed ◽  
Aphidius Ervi ◽  
Host Acceptance ◽  
Aphid Host

The molecular mechanisms that allow generalist parasitoids to exploit many, often very distinct hosts are practically unknown. The wasp Aphidius ervi, a generalist koinobiont parasitoid of aphids, was introduced from Europe into Chile in the late 1970s to control agriculturally important aphid species. A recent study showed significant differences in host preference and host acceptance (infectivity) depending on the host A. ervi were reared on. In contrast, no genetic differentiation between A. ervi populations parasitizing different aphid species and aphids of the same species reared on different host plants was found in Chile. Additionally, the same study did not find any fitness effects in A. ervi if offspring were reared on a different host as their mothers. Here, we determined the effect of aphid host species (Sitobion avenae versus Acyrthosiphon pisum reared on two different host plants alfalfa and pea) on the transcriptome of adult A. ervi females. We found a large number of differentially expressed genes (between host species: head: 2,765; body: 1,216; within the same aphid host species reared on different host plants: alfalfa versus pea: head 593; body 222). As expected, the transcriptomes from parasitoids reared on the same host species (pea aphid) but originating from different host plants (pea versus alfalfa) were more similar to each other than the transcriptomes of parasitoids reared on a different aphid host and host plant (head: 648 and 1,524 transcripts; body: 566 and 428 transcripts). We found several differentially expressed odorant binding proteins and olfactory receptor proteins in particular, when we compared parasitoids from different host species. Additionally, we found differentially expressed genes involved in neuronal growth and development as well as signaling pathways. These results point towards a significant rewiring of the transcriptome of A. ervi depending on aphid-plant complex where parasitoids develop, even if different biotypes of a certain aphid host species (A. pisum) are reared on the same host plant. This difference seems to persist even after the different wasp populations were reared on the same aphid host in the laboratory for more than 50 generations. This indicates that either the imprinting process is very persistent or there is enough genetic/allelic variation between A. ervi populations. The role of distinct molecular mechanisms is discussed in terms of the formation of host fidelity.

scholarly journals Host specialization of parasitoids and their hyperparasitoids on a pair of syntopic aphid species

2013 ◽  
Vol 103 (5) ◽  
pp. 530-537 ◽  
Author(s):  
Sämi Schär ◽  
Christoph Vorburger
Keyword(s):  
Population Genetic ◽  
Aphid Species ◽  
Aphis Fabae ◽  
Host Specialization ◽  
Dispersal Ability ◽  
Population Genetic Analysis ◽  
Aphid Parasitoids ◽  
Limited Dispersal ◽  
Males And Females ◽  
Lysiphlebus Cardui

AbstractParasitoids of herbivorous insects have frequently evolved specialized lineages exploiting hosts occurring on different plants. This study investigated whether host specialization is also observed when closely related parasitoids exploit herbivorous hosts sharing the same host plant. The question was addressed in economically relevant aphid parasitoids of theLysiphlebus fabarumgroup. They exploit two aphid species (Aphis fabae cirsiiacanthoidesandBrachycaudus cardui), co-occurring in mixed colonies (syntopy) on the spear thistle (Cirsium vulgare). Two morphologically distinguishable parasitoid lineages of the genusLysiphlebuswere observed and each showed virtually perfect host specialization on one of the two aphid species in this system. FromA. f. cirsiiacanthoides, only females emerged that morphologically belonged toLysiphlebus cardui, while males and females belonging toL. fabarumhatched fromB. cardui. Microsatellite analyses indicated clear genetic differentiation ofL. fabarumandL. cardui. L. carduicomprised only two distinct asexual lineages, one of which predominated throughout the area investigated. Population genetic analysis of sexualL. fabarumshowed evidence for relatively strong spatial structuring and limited dispersal ability. Hyperparasitoids emerged from a large proportion of aphid mummies. One species,Pachyneuron aphidis, was significantly associated withB. cardui/L. fabarummummies, indicating that host specialization may even extend to the trophic level above parasitoids.

scholarly journals Hymenopteran parasitoids (Hymenoptera: Aphidiidae) of cereal aphids (Sternorrhyncha: Aphidoidea) in winter wheat crops in Slovakia

2011 ◽  
Vol 39 (No. 3) ◽  
pp. 97-102 ◽  
Author(s):  
J. Praslička ◽  
S. Al Dobai ◽  
J. Huszár
Keyword(s):  
Winter Wheat ◽  
Aphidius Ervi ◽  
Cereal Aphids ◽  
Aphidius Rhopalosiphi ◽  
Aphid Parasitoids ◽  
Hymenopteran Parasitoids

During 1997–1999, occurrence of hymenopteran parasitoids of cereal aphids was observed in different localities in Slovakia. Altogether, seven species of aphid parasitoids were recorded. The total numbers of particular species over the last three years were as follows: Aphidius uzbekistanicus (160 individuals – 42.4%), Aphidius ervi (83 individuals – 22.0%), Aphidius rhopalosiphi (66 individuals – 17.5%), Ephedrus plagiator (40 individuals – 10.6%), Praon volucre (26 individuals – 6.9%), P. gallicum (1 individual – 0.3%), and Aphidius picipes (1 individual – 0.2%). The abundance of the parasitoids in each year was: 185 individuals (49.1%) in 1999, 122 individuals (32.4%) in 1998, and 70 individuals (18.6%) in 1997.  

A review of Aphidius Nees (Hymenoptera: Braconidae: Aphidiinae) in Iran: host associations, distribution and taxonomic notes

Zootaxa ◽  
2008 ◽  
Vol 1767 (1) ◽  
pp. 37 ◽  
Author(s):  
EHSAN RAKHSHANI ◽  
ALI ASGHAR TALEBI ◽  
PETR STARÝ ◽  
ŠELJKO TOMANOVIÇ ◽  
NICKOLAS G. KAVALLIERATOS ◽  
...  
Keyword(s):  
Species Identification ◽  
Identification Key ◽  
Food Plants ◽  
Plant Associations ◽  
Aphid Parasitoids ◽  
Host Associations

A survey of aphid parasitoids belonging to Aphidius Nees was conducted in several parts of Iran, and 17 species were identified between 2001 and 2005. Parasitoids were reared from field-collected aphids, and the tritrophic associations of parasitoids, their aphid hosts, and the respective food plants were determined. The species of Aphidius parasitoids are listed with their distribution and aphid-plant associations. An illustrated key for species identification is presented. Ambiguity of some characters is discussed, and the more reliable characters are indicated and used for the identification key.

Sign in / Sign up

Export Citation Format

Share Document