The Effect of Host-Plant Phylogenetic Isolation on Species Richness, Composition and Specialization of Insect Herbivores: A Comparison between Native and Exotic Hosts

Many studies have investigated the mechanisms behind the structure of arboreal ant assemblages. In this study, the objective was to evaluate the effect of availability of honeydew-producing colonies ofCalloconophora pugionata(Membracidae) on the structure of ant assemblages associated with the host plantMyrcia obovata(Myrtaceae) in an Atlantic forest of Minas Gerais (Brazil). Our experiment consisted in a gradual exclusion of hemipteran colonies out of the host plant crown and further record of the ant assemblage response (species richness, composition, and occurrence) to the presence and density of treehopper colonies. The hypothesis was that an increase in the number of trophobiont herbivores results in an increase in tending ant occurrence but a reduction in ant species diversity. Results corroborated our main hypothesis: membracids had a positive effect on the occurrence of ants but negative on species richness. Overall insect occurrence was also reduced with increasing inC. pugionatacolonies, probably due to strengthening dominant ant species territory sizes and intensification of patrolling.

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Interaction between bracken and its insect herbivores

Proceedings of the Royal Society of Edinburgh Section B Biological Sciences ◽

10.1017/s0269727000008046 ◽

1985 ◽

Vol 86 ◽

pp. 125-131

Author(s):

J. H. Lawton ◽

M. MacGarvin

Keyword(s):

Host Plant ◽

Natural Enemies ◽

Host Plants ◽

Insect Species ◽

Insect Herbivores ◽

The World ◽

Below Ground ◽

One Year ◽

The Impact ◽

Typical Site

SynopsisBracken in Britain is a host for 27 species of insect herbivores, with a further 11 species that either feed below ground (and are poorly studied), or appear to be only rarely associated with the plant. A typical site in northern England has an average of 15–16 of these species in any one year. Compared with perennial herbaceous angiosperms with similar wide distributions, bracken is not noticeably depauperate in the number of insect species that feed upon it. Bracken in others parts of the world is attacked by a wide variety of insects, with more species present in the geographical areas where bracken is most common.The ‘feeding niches’ of some of these insects are reviewed. Most are very rare relative to the biomass of their host plants, probably because of the impact of natural enemies; the effect of most of the insects upon their host-plant is consequently negligible.Reverse effects, of host-plant upon the insects, are subtle but poorly understood. Experiments to elucidate these effects are briefly outlined.

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Multi-scale patterns in the host specificity of plant-dwelling arthropods: the influence of host plant and temporal variation on species richness and assemblage composition of true bugs (Hemiptera)

Journal of Natural History ◽

10.1080/00222933.2011.597522 ◽

2011 ◽

Vol 45 (41-42) ◽

pp. 2577-2604 ◽

Cited By ~ 7

Author(s):

Melinda L. Moir ◽

Karl E.C. Brennan ◽

Murray J. Fletcher ◽

Jonathan D. Majer ◽

John M. Koch

Keyword(s):

Species Richness ◽

Temporal Variation ◽

Host Plant ◽

Host Specificity ◽

Assemblage Composition ◽

True Bugs ◽

Multi Scale

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The bigger the better? Vigour of the exotic host plant Calotropis procera (Apocynaceae) affects herbivory

Neotropical Biology and Conservation ◽

10.3897/neotropical.15.e55148 ◽

2020 ◽

Vol 15 (3) ◽

pp. 359-366

Author(s):

Geraldo Wilson Fernandes ◽

Jarcilene Silva de Almeida ◽

Maria Fernanda Vicente Rodrigues-Menelau ◽

Lucas Arantes-Garcia ◽

Samuel Novais

Keyword(s):

Host Plant ◽

Leaf Area ◽

Regional Scale ◽

Calotropis Procera ◽

Insect Herbivores ◽

Plant Vigour ◽

Seasonally Dry ◽

Shoot Size ◽

Vigorous Plant ◽

Leaf Herbivory

The Plant Vigour Hypothesis states that herbivores preferentially feed on the most vigorous plants within a plant population and/or the most vigorous modules within a plant. The goal of this study was to evaluate how shoot size (as an indication of module vigour) affects leaf herbivory in the host plant Calotropis procera, an exotic xerophyte perennial milkweed shrub. We predicted that the proportion of leaf area removed by insect herbivores would be positively related to shoot size. Eight patches were selected containing a varied number of C. procera individuals (5, 8, 29, 31, 55, 79, 116, and 172 individuals/patch) in the Brazilian seasonally dry vegetation (Caatinga), of which five individuals were randomly selected for further analysis. From each individual, three to six shoots were randomly selected, measured and had their leaves collected, for a total of approximately 200 leaves per patch. At the regional scale, the proportion of leaf area removed was positively affected by shoot size. In addition, this pattern was also found for the majority of the studied patches (29, 31, 55, 116, and 172 individuals/patch). Among the insect herbivores associated with C. procera, larvae of Danaus spp. (Lepidoptera: Nymphalidae) were commonly observed feeding on all patches. These herbivores present a specialized behaviour to circumvent the presence of latex in the host leaves. Although more vigorous plant modules should be better defended compared with the less vigorous modules, Danaus species were able to bypass host defences, and feed on healthy, rapidly growing and vigorous plant modules of C. procera, hence causing more damage to these modules.

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