Aphidius ervi

Several other examples of host plant recognition by hymenopteran parasitoids have been described recently. Six species of aphid parasitoids, Aphidius ervi, Trioxys sp., Praon sp., Aphelinus flavus, Lysiphlebus fabarum, and Aphidius rophalosiphi were most strongly attracted to their host aphid in combination with the damaged host plant [62]. For A. rhopalosiphi, three wheat volatiles were... 

Aphidius ervi Aphid sp. (Aphidinae) Host sex pheromone [attraction, increased parasitization] (4aS,7S,7aR)-Nepetalactone 26 (lR,4aS,7S,7aR)-nepetalactol 27 [77,78]... 

Aphidius ervi Acyrthosiphon pisum Broad bean + Du et al., 1996 Powell et al., 1998... 

Learning is not required for the aphid parasitoid Aphidius ervi to recognize pea plants that are damaged by its specific host, the pea aphid Acyrthosiphon pisum (Du et al, 1998 Powell et al., 1998). This parasitoid is far more attracted by pea plants infested by this host than by pea plants infested by a non-host, Aphis fabae. Implicated in the specificity of the signal is 6-methyl-5-hepten-2-one, a substance that was only detected in the odor profile of plants infested by A. pisum (Wadhams et al., 1999) the pure compound was found to be highly attractive to A. ervi (Du etal., 1998). 

Du, Y. J., Poppy, G. M. and Powell, W. (1996). Relative importance of semiochemicals from first and second trophic levels in host foraging behavior of Aphidius ervi. Journal of Chemical Ecology 22 1591-1605. 

Identification of semiochemicals released during aphid feeding that attract parasitoid Aphidius ervi. Journal of Chemical Ecology 24 1355-1368. 

Powell, W., Pennacchio, F., Poppy, G. M. and Tremblay, E. (1998). Strategies involved in the location of hosts by the parasitoid Aphidius ervi Haliday (Hymenoptera Braconidae Aphidiinae). Biological Control 11 104-112. 

Variability in induced plant volatiles complicates the reliance of natural enemies on these cues. One way of dealing with variability is through associative learning, which may allow parasitoids to learn which cues are most likely to lead them to suitable hosts at a particular time in a particular area. Moreover, recent studies suggest that plant volatile blends alone carry specific information on the herbivores by which they are attacked. For example, predatory mites can distinguish between the blends of apple trees infested by two herbivores species (20). Du et al. (21) showed that different aphid species elicit different volatile blends in bean plants and that the aphid parasitoid, Aphidius ervi, can use these differences to distinguish plants infested by its host. Aphis pisum from those infested by a nonhost. Aphis fabae... 

Du Y, Poppy GM, Powell W, Pickett JA, Wadhams LJ, Woodcock CM. Identification of semiochemicals released during aphid feeding that attract parasitoid Aphidius ervi. J. Chem. Ecol. 1998 24 1355-1368. 

Safari A, Hance T, Leroy PD, Frere I, Haubmge E, Destain J, Compde P, Thonart P. Placenta-like stmcture of the aphid endoparasitic Aphidius ervi a strategy of optimal resources acquisition. PLoS One. 2011 6(4) el8847. doi 10.1371/journal. pone.0018847. 

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