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Arbuscular mycorrhizal fungi (AMF) are known to reduce the growth of generalist root-feeding insects, but whether the same is true for a specialist insect is unknown. White clover (Trifolium repens) was inoculated with the AM fungi Glomus fasciculatum and Glomus mosseae individually and in combination, and larvae of the clover root weevil (Sitona lepidus) reared on mycorrhizal and non-mycorrhizal plants. On emergence, adult weevils were weighed and the percentage of larvae surviving to adulthood was calculated for each treatment. Larval survival to adulthood was increased by both species of fungi, but weight was unaffected. Larval feeding reduced foliar biomass, but had no effect when two fungi colonized the root system. Although larval survival was greatest in the dual fungal treatment, the proportion of grazed root nodules was lower, suggesting that AMF may improve root quality for the herbivore. Root feeding caused an increase in arbuscular colonization in the dual fungal treatment, and this may have enabled plants to tolerate herbivory, through enhanced mycorrhizal benefit. We conclude that a specialist root feeder is less affected by the presence of AMF than are generalist species. However, AMF enable a plant to tolerate the effects of root loss, and this is dependent on the number of mycorrhizal species in the root system.

Non‐indigenous, invasive invertebrate pests have a detrimental effect on the New Zealand economy through impacts on pasture and forage production. Estimates of the economic impact have varied from $800 million to $2 billion. This paper reviews the literature on plant biosecurity concerns in New Zealand, and examines five of the major invasive pests in pastoral agriculture: clover root weevil (Sitona lepidus Gyllenhal), Argentine stem weevil (Listronotus bonariensis Kuschel), lucerne weevil (Sitona discoideus Gyllenhal), and the lucerne aphids (Acyrthosiphon kondoi Shinji and Mac‐rosiphum pisi Shinji). The difficulties in assessing risk impact, and the limited value of extrapolation from results from other countries are discussed, as is the potential for using computer models in assessing potential impact. Recommendations for research approaches for the future are made.

The impact of a range of simulated pasture management options on damage to white clover resulting from the presence of the clover root weevil was evaluated in a glasshouse experiment. Pasture management options included were irrigation, cutting regime, cultivar, soil fertility (Olsen P) level, and nitrogen application. Two different soil types were used. White clover growth was significantly enhanced by moist soil conditions, as were clover root weevil (CRW) larval numbers recovered per plot. Few (

Self-reporting cameras have the potential to revolutionise the trapping networks utilised in pest management and biosecurity. A study was carried out to determine whether commercially available self-reporting camera systems that use Wi-Fi™ and GSM to transmit images to secure websites could be incorporated into trapping networks. Of 45 systems initially examined, one, the RedEye security camera, was laboratory tested. Tests showed that the standard optics package was incapable of distinguishing between clover root weevil (Sitona lepidus) and Argentine stem weevil (Listronotus bonariensis). An upgrade of the camera's optics enabled it be used to successfully monitor porina (Wiseana spp.) flight activity. While this result was encouraging, more research is needed before the technology can be incorporated into trapping networks. In particular, further thought is needed as to the level of image resolution that is required to ensure that the system is relevant to all pest management and biosecurity practitioners.

A biochemical viability assay was recently developed to quickly and easily assess the viability of small immobile arthropods including eggs intercepted on plant products On finding a viable specimen species identification often becomes the next hurdle This paper demonstrates that amplifiable DNA is present in a used biochemical viability assay solution and can be used for making taxonomic identifications Cryptically labelled heattreated and untreated eggs of three weevil species (Listronotus bonariensis Sitona lepidus and S discoideus) were first tested for viability then a 1135 bp fragment of the cytochrome c oxidase I gene was amplified from each viability assay solution in the presence of a fluorescent dye SYBR Green Melt curve analysis of the amplicons (n36) revealed three distinct melt profiles that correctly corresponded to each of the three weevil species This shows that the biochemical viability assay is compatible with the application of subsequent molecular identification methods which will facilitate the appropriate management response

The effect of clover root weevil (Sitona lepidus) (CRW) larval feeding on subterranean, suckling, striated and clustered clovers was compared with white clover in a glasshouse experiment. Growth of suckling, striated, and clustered clover was significantly reduced by CRW, approaching the levels of damage recorded in white clover. N fixation in suckling and clustered clovers was also reduced. Growth and nitrogen fixation of two subterranean clovers (cv. Denmark, cv. Leura) were changed relatively little by CRW larval feeding. The relatively high level of the isoflavonoid biochaninA that was present in subterranean clover roots may explain the species' tolerance of CRW. These results suggest that CRW may not pose a major threat to dryland farming systems based on subterranean clover. Keywords: annual clover, clover root weevil, roots, Trifolium dubium, Trifolium glomeratum, Trifolium striatum, Trifolium subterraneum