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We report the results of a structured expert elicitation to identify the most likely types of potential food system disruption scenarios for the UK, focusing on routes to civil unrest. We take a backcasting approach by defining as an end-point a societal event in which 1 in 2000 people have been injured in the UK, which 40% of experts rated as “Possible (20–50%)”, “More likely than not (50–80%)” or “Very likely (>80%)” over the coming decade. Over a timeframe of 50 years, this increased to 80% of experts. The experts considered two food system scenarios and ranked their plausibility of contributing to the given societal scenario. For a timescale of 10 years, the majority identified a food distribution problem as the most likely. Over a timescale of 50 years, the experts were more evenly split between the two scenarios, but over half thought the most likely route to civil unrest would be a lack of total food in the UK. However, the experts stressed that the various causes of food system disruption are interconnected and can create cascading risks, highlighting the importance of a systems approach. We encourage food system stakeholders to use these results in their risk planning and recommend future work to support prevention, preparedness, response and recovery planning.

Increasing concerns about global environmental change and food security have focused attention on the need for environmentally sustainable agriculture. This is agriculture that makes efficient use of natural resources and does not degrade the environmental systems that underpin it, or deplete natural capital stocks. We convened a group of 29 ‘practitioners’ and 17 environmental scientists with direct involvement or expertise in the environmental sustainability of agriculture. The practitioners included representatives from UK industry, non-government organizations and government agencies. We collaboratively developed a long list of 264 knowledge needs to help enhance the environmental sustainability of agriculture within the UK or for the UK market. We refined and selected the most important knowledge needs through a three-stage process of voting, discussion and scoring. Scientists and practitioners identified similar priorities. We present the 26 highest priority knowledge needs. Many of them demand integration of knowledge from different disciplines to inform policy and practice. The top five are about sustainability of livestock feed, trade-offs between ecosystem services at farm or landscape scale, phosphorus recycling and metrics to measure sustainability. The outcomes will be used to guide on-going knowledge exchange work, future science policy and funding.

We wish to place on record the rearing of a single female specimen of Brachymeria tibialis (Walker) on 13 July 2009 from a cocoon of Zygaena filipendulae (L.) collected on 5 June 2009 by one of us (RC) at Denbies Landbarn, Surrey, TQ 135499, a National Trust chalk downland site. This is the third recent specimen of this large and conspicuous chalcidoid noted in southern England (Jones, 2008; Beavis, 2009), and the first British rearing record. The specimen was determined by MRS and is deposited in the National Museums of Scotland. Askew & Shaw (2001) give morphological grounds for suspecting that two sibling species might be confused under the name B. tibialis in the Western Palaearctic, one associated with Zygaena species and the other more generalised. The presence of an evidently well-distributed British population provides entomologists living in southern England with a good opportunity to investigate this possibility through experimental rearings, by exposing a suitable selection of Lepidoptera prepupae and pupae to adult females reared from Zygaena species. We are indebted to the National Trust for permission to collect these insects at Denbies Landbarn and the Centre for Ecology and Hydrology Environmental Change Integrating Fund for support.

Previous European guidance for environmental risk assessment of genetically modified plants emphasized the concepts of statistical power but provided no explicit requirements for the provision of statistical power analyses. Similarly, whilst the need for good experimental designs was stressed, no minimum guidelines were set for replication or sample sizes. Furthermore, although substantial equivalence was stressed as central to risk assessment, no means of quantification of this concept was given. This paper suggests several ways in which existing guidance might be revised to address these problems. One approach explored is the ‘bioequivalence’ test, which has the advantage that the error of most concern to the consumer may be set relatively easily. Also, since the burden of proof is placed on the experimenter, the test promotes high-quality, well-replicated experiments with sufficient statistical power. Other recommendations cover the specification of effect sizes, the choice of appropriate comparators, the use of positive controls, meta-analyses, multivariate analysis and diversity indices. Specific guidance is suggested for experimental designs of field trials and their statistical analyses. A checklist for experimental design is proposed to accompany all environmental risk assessments.

Background/Question/Methods Pathogens play an important role for many host organisms, ranging from population regulation to species invasion, which in turn, have applications for issues such as disease control, pest control and biodiversity. However, much of our empirical understanding of host-pathogen ecology and evolution is derived from scenarios where the host is infected by a single pathogen or parasite. Molecular techniques have revealed that many infections in insect hosts are caused by several pathogen genotypes which differ phenotypically in their interaction with the host. This raises the question of how competing genotypes co-exist in the field. The simplest assumption would be that competition between genotypes within a host is a race to gain the greatest share of resources (host tissues), as in the tragedy of the commons. However, this would act to reduce genetic diversity rather than to maintain it. Results/Conclusions In this talk we aim to build upon recent developments in the literature by conducting single infection bioassays to obtain data on within-host growth and fitness parameters for phenotypically different and similar strains of nucleopolyhedroviruses in the Lepdipoteran host Spodoptera exigua. Using these data, a simple mechanistic mathematical model (a coupled system of differential equations) is derived and fitted. Predictions from this model agree with empirical findings, such as increased virus doses leading to decreased virus yields. Extending the single infection model, we assume that in mixed infections viruses compete for host resources, but otherwise act independently. The outcome of these simple assumptions leads to multiple infections producing some non-intuitive outcomes. For example, we predict that multiple infections can lead to significantly increased or decreased virus yield when compared to single infections. This resource mediated competitive synergistic or antagonistic relationship depends crucially on the composition of

The majority of studies on the regulation of insect populations by entomopathogenic fungi have been in the context of pest control, whereas there has been little research into how they may impact on natural populations of insects. The Adonis Blue (Polyommatus bellargus) and Chalkhill Blue (Polyommatus coridon) butterflies are species of Lepidoptera with particular conservation interest in the UK. Both of these species exist on the most northern edge of their climatic range in populations that are restricted to fragmented chalk grassland habitats in the South of England. Larvae of both butterflies feed on the same single host plant species (Hippocrepis comosa) and can be found in the soil during their development. It is therefore reasonable to assume that larvae will be exposed to soil entomopathogenic fungi. Polyommatus bellargus are bivoltine, and the distribution of early season larvae is very closely linked to warmer temperatures in sheltered microhabitats. The use of turf height and shelter category can accurately predict the occupancy of sites across a landscape for P. bellargus and define optimal and sub-optimal habitats, and it is thought a similar relationship exists for P. coridon. A combination of host- and habitat- selection could result in local adaptation of entomopathogenic fungi. Because shelter category is a proxy for temperature, it is possible that one of the driving selectors is the ability of fungi to operate at certain temperatures. Soil was collected from these habitats and turf height and shelter category was recorded. A total of 130 entomopathogenic fungi were extracted from 144 soil samples using Galleria melonella as bait. The in vitro growth of 40 of these isolates was investigated at a range of four different temperatures between 10 and 25ºC. The in vitro growth of a number of selected isolates was then profiled at a wider range of temperatures.

The analysis of multiple dose-response assays usually focuses on overall response patterns of synergism or antagonism. It is rare that more complex response patterns are described that incorporate dose-level or dose-dependent specific synergism and antagonism. We will present an example where we have adapted models from recently developed ecotoxicological mixture dose-response analysis to specifically describe the mortality response of cabbage moth larvae Mamestra brassicae exposed to combinations of pathogens and toxins. This forms part of a larger study investigating whether baculoviruses can be combined with other entomopathogens to achieve improved biological control of insect pests. Larvae of M. brassicae were exposed in the laboratory to a closely related nucleopolyhedrovirus Panolis flammea NPV (PaflNPV) or a homologous baculovirus Autographa californica NPV (AcalNPV) in mixtures with either Bacillus thuringiensis subsp. kurstaki (Btk), the pesticide Spinosad (active ingredients Spinosyns A & D) or the chemical Diethyldithiocarbamic acid (DETC) a sodium salt which has known suppression effects of the host immune system. To account for the antifeedant activity of Btk and Spinosad, the pathogen concentration received by each larva was adjusted relative to food consumption. Mortality of larvae due to each pathogen/toxin was assessed in each assay for 64 treatment combinations. Both PaflNPV and AcalNPV interacted in a similar way in mixtures with Btk and displayed a significant level of synergism across several of the doses tested. The interaction between Spinosad/PaflNPV and DETC/PaflNPV was more complex but was described by the adapted ecotoxicology independent action model. The use of such models enables us to identify doses at which synergy with another pathogen or toxin can increase baculovirus mortality in a Lepidopteran host.

Human activities have fundamental impacts on the distribution of species through altered land use, but also directly by dispersal of propagules. Rare long-distance dispersal events have a disproportionate importance for the spread of species including invasions. While it is widely accepted that humans may act as vectors of long-distance dispersal, there are few studies that quantify this process. We studied in detail a mechanism of human-mediated dispersal (HMD). For two plant species we measured, over a wide range of distances, how many seeds are carried by humans on shoes. While over half of the seeds fell off within 5m, seeds were regularly still attached to shoes after 5km. Semi-mechanistic models were fitted, and these suggested that long-distance dispersal on shoes is facilitated by decreasing seed detachment probability with distance. Mechanistic modelling showed that the primary vector, wind, was less important as an agent of long-distance dispersal, dispersing seeds less than 250m. Full dispersal kernels were derived by combining the models for primary dispersal by wind and secondary dispersal by humans. These suggest that walking humans can disperse seeds to very long distances, up to at least 10km, and provide some of the first quantified dispersal kernels for HMD.

1. Spatial habitat structure can influence the likelihood of patch colonisation by dispersing individuals, and this likelihood may differ according to trophic position, potentially leading to a refuge from parasitism for hosts. 2. Whether habitat patch size, isolation, and host-plant heterogeneity differentially affected host and parasitoid abundance, and parasitism rates was tested using a tri-trophic thistle–herbivore–parasitoid system. 3. Cirsium palustre thistles (n = 240) were transplanted in 24 blocks replicated in two sites, creating a range of habitat patch sizes at increasing distance from a pre-existing source population. Plant architecture and phenological stage were measured for each plant and the numbers of the herbivore Tephritis conura and parasitoid Pteromalus elevatus recorded. 4. Mean herbivore numbers per plant increased with host-plant density per patch, but parasitoid numbers and parasitism rates were unaffected. Patch distance from the source population did not influence insect abundance or parasitism rates. Parasitoid abundance was positively correlated with host insect number, and parasitism rates were negatively density dependent. Host-plant phenological stage was positively correlated with herbivore and parasitoid abundance, and parasitism rates at both patch and host-plant scales. 5. The differential response between herbivore and parasitoid to host-plant density did not lead to a spatial refuge but may have contributed to the observed parasitism rates being negatively density dependent. Heterogeneity in patch quality, mediated by variation in host-plant phenology, was more important than spatial habitat structure for both the herbivore and parasitoid populations, and for parasitism rates.

Vaccines that target blood-feeding disease vectors, such as mosquitoes and ticks, have the potential to protect against the many diseases caused by vector-borne pathogens. We tested the ability of an anti-tick vaccine derived from a tick cement protein (64TRP) of Rhipicephalus appendiculatus to protect mice against tick-borne encephalitis virus (TBEV) transmitted by infected Ixodes ricinus ticks. The vaccine has a “dual action” in immunized animals: when infested with ticks, the inflammatory and immune responses first disrupt the skin feeding site, resulting in impaired blood feeding, and then specific anti-64TRP antibodies cross-react with midgut antigenic epitopes, causing rupture of the tick midgut and death of engorged ticks. Three parameters were measured: “transmission,” number of uninfected nymphal ticks that became infected when cofeeding with an infected adult female tick; “support,” number of mice supporting virus transmission from the infected tick to cofeeding uninfected nymphs; and “survival,” number of mice that survived infection by tick bite and subsequent challenge by intraperitoneal inoculation of a lethal dose of TBEV. We show that one dose of the 64TRP vaccine protects mice against lethal challenge by infected ticks; control animals developed a fatal viral encephalitis. The protective effect of the 64TRP vaccine was comparable to that of a single dose of a commercial TBEV vaccine, while the transmission-blocking effect of 64TRP was better than that of the antiviral vaccine in reducing the number of animals supporting virus transmission. By contrast, the commercial antitick vaccine (TickGARD) that targets only the tick's midgut showed transmission-blocking activity but was not protective. The 64TRP vaccine demonstrates the potential to control vector-borne disease by interfering with pathogen transmission, apparently by mediating a local cutaneous inflammatory immune response at the tick-feeding site