Host phylogeny and specialisation in parasitoids

Abstract

The host range of insect parasitoids and herbivores is influenced by both preference-related traits which mediate host choice behaviour, and performance-related traits which mediate the physiological suitability of the consumer-resource interaction. In a previous study, we characterised the influence of preference- and performance-related traits on the host range of the aphid parasitoid Binodoxys communis (Hymenoptera: Braconidae) and herein we build upon those data sets by mapping a series of these traits onto the phylogeny of the (aphid) host species. We found a strong effect of host phylogeny on overall parasitoid reproduction on the 20 host species tested, but no effect of the phylogeny of host plants of the aphids. We found an effect of aphid phylogeny on host acceptance and sting rates (related to preference) from behavioural observations and for pupal survivorship (related to performance), showing that both classes of traits show phylogenetic conservatism with respect to host species.

Assessing European Egg Parasitoids as a Mean of Controlling the Invasive South American Tomato Pinworm Tuta absoluta

“…It has been shown that Trichogramma parasitoids prefer hosts with relatively big eggs [34] but the eggs of T. absoluta are, by comparison, three times smaller than the eggs of E. kuehniella used in the rearing. Furthermore, we found a positive relationship between the number of parasitized eggs and the proportion of females accepting T. absoluta as host, demonstrating that parasitism levels were directly linked to the willingness of females to attack the host (as demonstrated in other parasitoid systems [25], [32], [35], [36]). Second, low parasitism may result not only from rejection of T. absoluta eggs as host but rather from the poor capacity of some Trichogramma species/strains to cope with specific tomato plant characteristics.…”

“…The low parasitism recorded for some strains may be attributed to two factors. First, in parasitoids, host specificity is mediated in part by host recognition and acceptance by the adult female parasitoid [25], [32], [33]. It has been shown that Trichogramma parasitoids prefer hosts with relatively big eggs [34] but the eggs of T. absoluta are, by comparison, three times smaller than the eggs of E. kuehniella used in the rearing.…”

Weevils as Targets for Biological Control, and the Importance of Taxonomy and Phylogeny for Efficacy and Biosafety

“…This principle is well accepted and tested in weed biological control [80,81]. Insect biological control is complicated by an extra trophic level (host food plant), not to mention the much larger number of potential non-target hosts, and although studies have shown that host phylogeny is often a strong factor in host selection by parasitoids and indeed parasitoid performance in a host (e.g., [82]), host ecology can also be a determinant of host selection. For example, host use by parasitoids of leaf-mining insects was shown to be capable of spanning several orders of insects [83].…”

Identification of Top-Down Forces Regulating Cotton Aphid Population Growth in Transgenic Bt Cotton in Central China

“…When considering Aphidiine parasitoids, L. japonica proved to be a key natural enemy of cotton aphid in Northern China [44], [48]. This species is also a natural enemy of phylogenetically closely related aphid species [49] e.g. the soybean aphid Aphis glycines Matsumura in Japan and Indonesia [50] and the brown citrus aphid Toxoptera citricida Kirkaldy [51], [52].…”