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European Union Seventh Framework Programme (FP7/2007–2013); Conservation biological control (CBC) is a sustainable approach to pest management that can contribute to a reduction in pesticide use as part of an Integrated Pest Management (IPM) strategy. CBC is based on the premise that countering habitat loss and environmental disturbance associated with intensive crop production will conserve natural enemies, thus contributing to pest suppression. The abundance and diversity of natural enemies increases in response to a variety of conservation measures, including plant and habitat diversification, a reduction in cropping intensity, and increased landscape complexity. However, the response of natural enemy populations to conservation measures is not consistent; often it fails to translate into pest suppression or improved crop yield, and is seldom utilised in commercial crop production settings. CBC is a complex strategy drawing on a number of ecological and behavioural processes, operating at multiple scales, and mediated by management actions that are, potentially, targeted at a wide range of pest organisms. Given this inherent complexity, it is not surprising that the scientific understanding of CBC is incomplete, or that the design and adoption of reliable CBC prescriptions have proved elusive. To tackle this, we consolidate existing knowledge of CBC using a simple conceptual model that organises the functional elements of CBC into a common, unifying framework. We identify and integrate the key biological processes affecting natural enemies and their biological control function across local and regional scales, and consider the interactions, interdependencies and constraints that determine the outcome of CBC strategies. Conservation measures are often effective in supporting natural enemy populations but their success cannot be guaranteed; the greatest limitation to the development of effective CBC is due to a failure to adequately direct biological control services to achieve suppression of the target pests. By considering the performance of these and other components of CBC within the context of an integrated system, we believe that the limiting factors can be identified, and removed, allowing effective CBC strategies to be implemented.

Sustainable intensification is a process by which agricultural productivity is enhanced whilst also creating environmental and social benefits. We aimed to identify practices likely to deliver sustainable intensification, currently available for UK farms but not yet widely adopted. We compiled a list of 18 farm management practices with the greatest potential to deliver sustainable intensification in the UK, following a well-developed stepwise methodology for identifying priority solutions, using a group decision-making technique with key agricultural experts. The list of priority management practices can provide the focal point of efforts to achieve sustainable intensification of agriculture, as the UK develops post-Brexit agricultural policy, and pursues the second Sustainable Development Goal, which aims to end hunger and promote sustainable agriculture. The practices largely reflect a technological, production-focused view of sustainable intensification, including for example, precision farming and animal health diagnostics, with less emphasis on the social and environmental aspects of sustainability. However, they do reflect an integrated approach to farming, covering many different aspects, from business organization and planning, to soil and crop management, to landscape and nature conservation. For a subset of ten of the priority practices, we gathered data on the level of existing uptake in English and Welsh farms through a stratified survey in seven focal regions. We find substantial existing uptake of most of the priority practices, indicating that UK farming is an innovative sector. The data identify two specific practices for which uptake is relatively low, but which some UK farmers find appealing and would consider adopting. These practices are: prediction of pest and disease outbreaks, especially for livestock farms; staff training on environmental issues, especially on arable farms.

Introduction Collection of volatiles from plant roots poses technical challenges due to difficulties accessing the soil environment without damaging the roots. Objectives To validate a new non-invasive method for passive sampling of root volatiles in situ, from plants grown under field conditions, using solid phase micro-extraction (SPME). Methods SPME fibres were inserted into perforated polytetrafluoroethene (PTFE) tubes positioned in the soil next to broccoli plants for collection of root volatiles pre- and post-infestation with Delia radicum larvae. After sample analysis by gas chromatography-mass spectrometry (GC-MS), principal component analysis (PCA) was applied to determine differences in the profiles of volatiles between samples. Results GC-MS analysis revealed that this method can detect temporal changes in root volatiles emitted before and after Delia radicum damage. PCA showed that samples collected pre- and post-infestation were compositionally different due to the presence of root volatiles induced by D. radicum feeding. Sulphur containing compounds, in particular, accounted for the differences observed. Root volatiles emission patterns post-infestation are thought to follow the feeding and developmental progress of larvae. Conclusion This study shows that volatiles released by broccoli roots can be collected in situ using SPME fibres within perforated PTFE tubes under field conditions. Plants damaged by Delia radicum larvae could be distinguished from plants sampled pre-infestation and soil controls on the basis of larval feeding-induced sulphur-containing volatiles. These results show that this new method is a powerful tool for non-invasive sampling of root volatiles below-ground. Copyright © 2016 John Wiley & Sons, Ltd.

Weeds, pests and diseases in Rubus plantations can have significant economic impact through their negative effects on yield and the costs of implementing control measures. Yield losses can be particularly high for certain pests and diseases, in some cases leading to total plantation losses. While the costs of weed control are rarely quantified, weeds can be a major detriment to profit in Rubus and other perennial fruit production systems. Although chemical control methods can be effective, growers are under increasing pressure to produce fruit sustainably with reduced chemical inputs to mitigate health risks and environmental damage (e.g. Łozowicka et al. 2012). In Europe, this has led to the requirement for each EU Member State to implement a National Action Plan with Integrated Pest Management (IPM; where the term ‘pest’ covers all injurious biotic stressors attacking crop plants) as a central crop protection strategy. Agroecological approaches offer an opportunity to develop sustainable weed, pest and disease management interventions by developing an understanding of the system processes and functions contributing to pest and disease regulation (Birch et al. 2011; Kremen et al. 2012). A framework for adopting an agroecological approach to promote integrated pest and disease management is provided by Birch et al. (2011) and includes (i) use of pest-resistant cultivars, (ii) optimising synthetic pesticide and biopesticide applications, (iii) use of bioactive substances (e.g. pheromones, semiochemicals), (iv) enhancing biocontrol using natural enemies, and (v) ecological engineering of habitats and landscapes to optimise pest and disease suppression. This chapter reports on recent progress and available options for these management measures in Rubus plantations.

Summary Push-pull or stimulo-deterrent cropping systems combine a trap crop or other attractant or arrestant stimulus distant from the crop and a deterrent or repellent near or within the target crop, to divert pests, reducing their populations on the target crop. Although the concept is decades old, there are few successful applications in pest management. In this article, we address this shortcoming by offering a mechanistic conceptual framework of push-pull systems, based on the cues, sensory modalities, pest behaviours and spatial ranges over which they can occur during host selection and that can influence pest distribution. We review published work on push-pull systems in the light of this framework, finding that the literature tends to focus on longer-range stimulo-deterrence strategies rather than the full range of cues involved and modalities that can come into play, with imperfect understanding of cues involved in most systems. The imbalance in research emphasis and incomplete understanding of push-pull mechanisms suggest opportunities to improve and broaden the palette of potential push-pull technologies. The framework also helps clarify other aspects important for achieving success with push-pull methods, including the role of synergy, deployment geometry, intraspecific variability and the wider arthropod community in these systems. Synthesis and applications. A conceptual and mechanistic framework is provided for the development of push-pull or stimulo-deterrent pest management approaches. This framework informs a proposed research agenda for designing push-pull technologies. That agenda involves including all cues and modalities, exploiting synergies, tuning deployment geometry in accordance with these factors. It also considers pest and crop dynamics and the arthropod community of the system. The framework can benefit managers by helping them to consider more fully the behaviour of the target pests when creating crop and non-crop geometries to achieve push-pull benefits. Research-based push-pull systems will be better implemented and modified by producers if they understand how insects respond to sources of push and pull in the system, allowing effective monitoring and fine-tuning to increase effectiveness of this specialized component of integrated pest management.

We consider modelling the movements of larvae using individual bioassays in which data are collected at a high-frequency rate of five observations per second. The aim is to characterize the behaviour of the larvae when exposed to attractant and repellent compounds. Mixtures of diffusion processes, as well as Hidden Markov models, are proposed as models of larval movement. These models account for directed and localized movements, and successfully distinguish between the behaviour of larvae exposed to attractant and repellent compounds. A simulation study illustrates the advantage of using a Hidden Markov model rather than a simpler mixture model. Practical aspects of model estimation and inference are considered on extensive data collected in a study of novel approaches for the management of cabbage root fly.

In legal frameworks worldwide, genetically modified plants (GMPs) are subjected to pre-market environmental risk assessment (ERA) with the aim of identifying potential effects on the environment. In the European Union, the EFSA Guidance Docuinent introduces the rationale that GMPs, as well as their newly produced metabolites, represent the potential stressor to be evaluated during ERA. As a consequence, during several phases of ERA for cultivation purposes, it is considered necessary to use whole plants or plant parts in experimental protocols. The importance of in planta studies as a strategy to address impacts of GMPs tin non-target organislns is demonstrated, to evaluate both effects due to the intended modification in plant phenotype (e.g. expression of Cry proteins) and effects due to unintended modifications in plant phenotype resultihg from the transformation process (e.g. due to somaclonal variations or pleiotropic effects). In planta tests are also necessary for GMPs in which newly expressed metabolites cannot easily be studied in vitro. This paper reviews the scientific literature supporting the choice of in planta studies as a fundamental tool in ERA of GMPs in cultivation dossiers; the evidence indicates they can realistically mimic the ecological relationships occurring in their receiving environments and provide important insights into the biology and sustainable management of GMPs.

The green peach aphid, Myzus persicae (Sulzer) (Homoptera: Aphididae), damages potato worldwide. In this study, we investigated 21 Commonwealth Potato Collection (CPC) accessions from seven wild Solanum species in order to identify sources of resistance against the green peach aphid. Test plants of wild potato species were grown from seed. After 4 weeks, 5 wingless adult aphids were put onto each test plant. The number of aphids was counted after 24 h, 7 and 10 days. At the second screening stage, plants were tested after 4 week’s growth, using the same aphid bioassay as in the first stage screen. Results showed that the most resistant Solanum species to M. persicae were S. trifidum and S. palustre and the most susceptible species tested was S. sanctae-rosae. Stability of the detected aphid resistance during plant development was measured by the correlation of repeated tests S. jamesii (CPC 7166) and S. trifidum (CPC 7123) were significantly more correlated than other accessions tested. The number of glandular hairs on these two resistant species was low and medium respectively. Therefore, resistance of these CPC accessions does not appear to depend on the presence of glandular hairs. Based on glasshouse tests, these two CPC accessions may be useful for novel aphid resistance traits in potato to M. persicae.

Introduction Research on plant root chemical ecology has benefited greatly from recent developments in analytical chemistry. Numerous reports document techniques for sampling root volatiles, although only a limited number describe in situ collection. Objectives To demonstrate a new method for non-invasive in situ passive sampling using solid phase micro extraction (SPME), from the immediate vicinity of growing roots. Methods SPME fibres inserted into polyfluorotetrafluoroethylene (PTFE) sampling tubes located in situ which were either perforated, covered with stainless steel mesh or with microporous PTFE tubing, were used for non-invasive sub-surface sampling of root volatiles from glasshouse-grown broccoli. Sampling methods were compared with above surface headspace collection using Tenax TA. The roots were either mechanically damaged or infested with Delia radicum larvae. Principal component analysis (PCA) was used to investigate the effect of damage on the composition of volatiles released by broccoli roots. Results Analyses by gas chromatography-mass spectrometry (GC-MS) with SPME and automated thermal desorption (ATD) confirmed that sulphur compounds, showing characteristic temporal emission patterns, were the principal volatiles released by roots following insect larval damage. Use of SPME with in situ perforated PTFE sampling tubes was the most robust method for out-of-lab sampling. Conclusion This study describes a new method for non-invasive passive sampling of volatiles in situ from intact and insect damaged roots using SPME. The method is highly suitable for remote sampling and has potential for wide application in chemical ecology/root/soil research. Copyright © 2016 John Wiley & Sons, Ltd.

Collection of volatiles from plant roots poses technical challenges due to difficulties accessing the soil environment without damaging the roots.To validate a new non-invasive method for passive sampling of root volatiles in situ, from plants grown under field conditions, using solid phase micro-extraction (SPME).SPME fibres were inserted into perforated polytetrafluoroethene (PTFE) tubes positioned in the soil next to broccoli plants for collection of root volatiles pre- and post-infestation with Delia radicum larvae. After sample analysis by gas chromatography-mass spectrometry (GC-MS), principal component analysis (PCA) was applied to determine differences in the profiles of volatiles between samples.GC-MS analysis revealed that this method can detect temporal changes in root volatiles emitted before and after Delia radicum damage. PCA showed that samples collected pre- and post-infestation were compositionally different due to the presence of root volatiles induced by D. radicum feeding. Sulphur containing compounds, in particular, accounted for the differences observed. Root volatiles emission patterns post-infestation are thought to follow the feeding and developmental progress of larvae.This study shows that volatiles released by broccoli roots can be collected in situ using SPME fibres within perforated PTFE tubes under field conditions. Plants damaged by Delia radicum larvae could be distinguished from plants sampled pre-infestation and soil controls on the basis of larval feeding-induced sulphur-containing volatiles. These results show that this new method is a powerful tool for non-invasive sampling of root volatiles below-ground. Copyright © 2016 John WileySons, Ltd.

Drivers behind food security and crop protection issues are discussed in relation to food losses caused by pests. Pests globally consume food estimated to feed an additional one billion people. Key drivers include rapid human population increase, climate change, loss of beneficial on-farm biodiversity, reduction in per capita cropped land, water shortages, and EU pesticide withdrawals under policies relating to 91/414 EEC. IPM (Integrated Pest Management) will be compulsory for all EU agriculture by 2014 and is also being widely adopted globally. IPM offers a 'toolbox' of complementary crop- and region-specific crop protection solutions to address these rising pressures. IPM aims for more sustainable solutions by using complementary technologies. The applied research challenge now is to reduce selection pressure on single solution strategies, by creating additive/synergistic interactions between IPM components. IPM is compatible with organic, conventional, and GM cropping systems and is flexible, allowing regional fine-tuning. It reduces pests below economic thresholds utilizing key 'ecological services', particularly biocontrol. A recent global review demonstrates that IPM can reduce pesticide use and increase yields of most of the major crops studied. Landscape scale 'ecological engineering', together with genetic improvement of new crop varieties, will enhance the durability of pest-resistant cultivars (conventional and GM). IPM will also promote compatibility with semiochemicals, biopesticides, precision pest monitoring tools, and rapid diagnostics. These combined strategies are urgently needed and are best achieved via multi-disciplinary research, including complex spatio-temporal modelling at farm and landscape scales. Integrative and synergistic use of existing and new IPM technologies will help meet future food production needs more sustainably in developed and developing countries, in an era of reduced pesticide availability. Current IPM research gaps are identified and discussed.

The European large raspberry aphid Amphorophora idaei Borner (Homoptera: Aphididae) is a virus vector of at least four plant virus complexes making it the most important aphid pest of raspberries in Northern Europe. An approach combining a bottom-up control (plant resistance) and a top-down control (an aphid parasitoid) using Aphidius ervi Haliday (Hymenoptera: Aphidiinae) was investigated in the laboratory. Aphid performance (pre-reproductive period, total reproductive output, lifespan and r m) were compared when reared on both a susceptible cultivar and a resistant cultivar with significantly poorer performance on the resistant cultivar. Parasitoid attack behaviour increased with aphid density on both cultivars, but was significantly lower on resistant plants than susceptible plants. Aphids showed a greater tendency to drop from the plant when feeding on resistant plants compared with susceptible plants. The significance of the results is discussed in the context of possible control of the aphid using these combined methods.

The interactions of genetically modified (GM) crops with soil species and ecosystems is complex, requiring both specific and broad spectrum assessments. In the ECOGEN project we undertook experiments at three scales of increasing complexity, using Bt maize expressing the Cry1Ab protein from Bacillus thuringiensis as an example. Test species were selected for laboratory-scale experiments to represent taxonomic groups that we could also monitor at glasshouse and field scales (e.g., nematodes, protozoa, micro-arthropods, earthworms, and snails). In the laboratory, single species were exposed to purified Cry1Ab protein or to Bt maize leaf powder incorporated into simplified diets under controlled conditions. In the glasshouse, multiple test species and soil microbial communities taken from ECOGEN's field sites were exposed to Bt maize plants growing under glasshouse or mesocosm conditions. In the field, evaluations were conducted on our selected indicator groups over multiple sites and growing seasons. Field evaluation included assessment of effects due to the local environment, crop type, seasonal variation and conventional crop management practice (tillage and pesticide use), which cannot be assessed in the glasshouse. No direct effects of Cry1Ab protein or Bt leaf residues were detected on our laboratory test organisms, but some significant effects were detected in the glasshouse. Total nematode and protozoan numbers increased in field soil under Bt maize relative to conventional maize, whilst microbial community structure and activity were unaffected. Field results for the abundance of nematodes and protozoa showed some negative effects of Bt maize, thus contradicting the glasshouse results. However, these negative results were specific to particular field sites and sampling times and therefore were transient. Taking the overall variation found in maize ecosystems at different sites into account, any negative effects of Bt maize at field scale were judged to be indirect and no greater than the impacts of crop type, tillage and pesticide use. Although the ECOGEN results were not predictive between the three experimental scales, we propose that they have value when used with feedback loops between the scales. This holistic approach can used to address questions raised by results from any level of experimentation and also for putting GM crop risk:benefit into context with current agricultural practices in regionally differing agro-ecosystems.

1. Few entomological studies include soil-dwelling insects in mainstream ecological theory, for example the preference–performance debate. The preference–performance hypothesis predicts that when insect herbivores have offspring with limited capacity to relocate in relation to a host plant, there is a strong selection pressure for the adult to oviposit on plants that will maximise offspring performance. 2. This paper discusses the proposition that insect herbivores that live above ground, but have soil-dwelling offspring, should be included in the preference–performance debate. Twelve relevant studies were reviewed to assess the potential for including soil insects in this framework, before presenting a preliminary case study using the clover root weevil (Sitona lepidus) and its host plant, white clover (Trifolium repens). 3. Maternal S. lepidus preferentially oviposited on T. repens plants that had rhizobial root nodules (which enhance offspring performance) rather than T. repens plants without nodules, despite plants having similar foliar nutritional quality. This suggests that adult behaviour above ground was influenced by below-ground host-plant quality. 4. A conceptual model is presented to describe how information about the suitability for offspring below ground could underpin oviposition behaviour of parental insects living above ground, via plant- and soil-mediated semiochemicals. These interactions between genetically related, but spatially separated, insect herbivores raise important evolutionary questions such as how induced plant responses above ground affect offspring living below ground and vice versa.

We consider a reaction-diffusion system for spatial spread of pest resistance to host plant resistance genes which is based on the Lotka-Volterra predator-prey equations, with logistic growth of the resource level and a diffusion term added to account for spatial spread of the pest. The model is phenotype specific, in which a pest subpopulation's fitness comes down to a balance between its resource assimilation rate and its respiration rate. We derive an expression for the rate of spatial spread of the resistant pest types from an initial point source, and discuss its relevance for adaptive pest resistance management strategies. Using results for an analogous single-species reaction-diffusion model in heterogeneous media, we consider the likely impact of pest-susceptible plant refugia on the speed of the travelling wave of resistant pests, and simultaneously the expected trade-off, in terms of crop yield decrease, when refugia are included. We also explore the possibility that resistance breaking by the pest population is not an inevitable phenomenon, particularly when refugia of the appropriate size are used.

We consider modelling the movements of larvae using individual bioassays in which data are collected at a high-frequency rate of five observations per second. The aim is to characterize the behaviour of the larvae when exposed to attractant and repellent compounds. Mixtures of diffusion processes, as well as Hidden Markov models, are proposed as models of larval movement. These models account for directed and localized movements, and successfully distinguish between the behaviour of larvae exposed to attractant and repellent compounds. A simulation study illustrates the advantage of using a Hidden Markov model rather than a simpler mixture model. Practical aspects of model estimation and inference are considered on extensive data collected in a study of novel approaches for the management of cabbage root fly.

We investigated if the activity of soil invertebrates (protozoa and earthworms) affected the performance of barley and if effects propagated higher up the above-ground food chain into herbivores (cereal aphid, Sitobion avenae). Barley plants were grown individually in microcosms containing defaunated soil and grass residues. Plants were grown in soil containing: a) no added fauna, b) protozoa, c) earthworms, or d) protozoa and earthworms. After 7 weeks growth at 20°C three adult cereal aphids were added to each plant on separate leaves. The aphids were allowed to grow and reproduce for another 2 weeks before the experiment was destructively sampled. Amounts of mineral N in the soil and leached from the microcosms were significantly reduced by the presence of soil animals. Correspondingly plant biomass and total plant N content were increased significantly by soil animals, protozoa in particular. The different mechanisms responsible for changes in nutrient turnover in presence of protozoa and earthworms are discussed. Aphid performance was strongly influenced by the presence of protozoa, but not by earthworms. In the presence of protozoa the numbers and biomass of adult and juvenile aphids were significantly increased. These effects are likely due to an increased N content in barley plants and consequently increased nitrogen availability to aphids. The results underline that the detritivore and herbivore systems are intimately linked.

Transgenic crops genetically engineered for enhanced insect resistance should be compatible with other components of IPM for the pest resistance to be durable and effective. An experimental potato line was genetically engineered to express an anti-aphid plant protein (snowdrop lectin, GNA), and assessed for possible interactions of the insect resistance gene with a beneficial pest predator. These extended laboratory studies are the first to demonstrate adverse tri-trophic interactions involving a lectin- expressing transgenic crop, a target pest aphid and a beneficial aphidophagous predator. When adult 2-spot ladybirds (Adalia bipunctata[L.]) were fed for 12 days on peach-potato aphids (Myzus persicae Sulzer) colonising transgenic potatoes expressing GNA in leaves, ladybird fecundity, egg viability and longevity significantly decreased over the following 2–3 weeks. No acute toxicity due to the transgenic plants was observed, although female ladybird longevity was reduced by up to 51%. Adverse effects on ladybird reproduction, caused by eating peach-potato aphids from transgenic potatoes, were reversed after switching ladybirds to feeding on pea aphids from non-transgenic bean plants. These results demonstrate that expression of a lectin gene for insect resistance in a transgenic potato line can cause adverse effects to a predatory ladybird via aphids in its food chain. The significance of these potential ecological risks under field conditions need to be further evaluated.

The effects of concanavalin A (ConA), a glucose/mannose-specific lectin from jackbean (Canavalia ensiformis), on insect crop pests from two different orders, Lepidoptera and Homoptera, were investigated. When fed to larvae of tomato moth (Lacanobia oleracea) at a range of concentrations (0.02–2.0% of total protein) in artificial diet, ConA decreased survival, with up to 90% mortality observed at the highest dose level, and retarded development, but had only a small effect on larval weight. When fed to peach-potato aphids (Myzus persicae) at a range of concentrations (1–9μM) in liquid artificial diet, ConA reduced aphid size by up to 30%, retarded development to maturity, and reduced fecundity (production of offspring) by >35%, but had little effect on survival. With both insects, there was a poor correlation between lectin dose and the quantitative effect. Constitutive expression of ConA in transgenic potatoes driven by the CaMV 35S promoter resulted in the protein accumulating to levels lower than predicted, possibly due to potato not being able to adequately reproduce the post-translational processing of this lectin which occurs in jackbean. However, the expressed lectin was functionally active as a haemagglutinin. Bioassay of L. oleracea larvae on ConA-expressing potato plants showed that the lectin retarded larval development, and decreased larval weights by >45%, but had no significant effect on survival. It also decreased consumption of plant tissue by the larvae. In agreement with the diet bioassay results, ConA-expressing potatoes decreased the fecundity of M. persicae by up to 45%. ConA thus has potential as a protective agent against insect pests in transgenic crops.

Plants from two cultivars of forage rape and one cultivar of oilseed rape were inoculated with turnip root fly (Delia floralis) eggs at either 4 or 6 weeks prior to harvest, or, alternatively, were artificially damaged by mechanically removing approximately one-third of the root volume. Larval damage increased the total glucosinolate content of the roots. In contrast, artificial damage reduced the total glucosinolate content of the roots, with the levels decreasing as the time interval between damage and harvest lengthened. Turnip root fly larval damage also modified the glucosinolate composition of the roots, with the proportion of indoleglucosinolates increasing significantly. No such changes were observed in the artificially damaged roots. Neither type of damage appeared to affect the total glucosinolate content of foliar samples significantly, when averaged over all cultivars, but it was of interest to note that the proportion of glucobrassicin present in the leaves of the oilseed rape cultivar, Ariana, was consistently greater in both the larval and artificially root damaged plants compared with undamaged plants of the same cultivar. These results are discussed in relation to sulphur availability and the validity of root trimming as a simulation for turnip root fly damage.

Plants produce a wide range of defensive compounds (allomones) to protect themselves from predators and pathogens. Selected allomones have been screened against plant parasitic nematodes for a range of activities such as antihatching, repellent, nematotoxic, anti-feedant or anti-virus vectoring activities and inhibition of female development. Plant-growth stimulation and anti-nematode activities complementary to host-plant resistance were also studied. Examples are presented of ways in which plant-derived compounds can interfere with the life cycles of nematodes and their close relationships with host plants. The potential of plant-derived compounds in future environmentally benign integrated pest management of nematodes is discussed

Three genotypes of forage rape and two of winter oilseed rape (Brassica napus L), grown in a glasshouse, were inoculated with Delia floralis Fall eggs at 5 weeks and their roots were sampled after a further 6 weeks of larval attack. Individual and total glucosinolates were examined in seed and roots using HPLC. No clear relationship was found between seed and root total or individual glucosinolate content. Major differences in glucosinolate composition were found between uninoculated control roots. In two doublezero oilseed rapes, phenylethyl glucosinolate was predominant whereas, in the three forage rapes, 2-hydroxy-but-3-enyl was the major glucosinolate. Attack by D floralis larvae considerably modified both concentrations and relative proportions of individual glucosinolates in roots. The total glucosinolate content decreased for all of the rapes except double-zero oilseed rape WRG35. In all rapes the proportion of aromatic to aliphatic glucosinolates increased after attack, largely due to increased levels of indolebased glucosinolates; 1-methyoxy-3-indole methyl glucosinolate increased by over 88%. The total aliphatic glucosinolate content of all rape roots with the exception of WRG35 was reduced by 39–56% after attack. Possible causes for altered glucosinolate metabolism are discussed in relation to observed differences in levels of susceptibility to turnip root fly attack.

Soils from field sites at Foulum (DK), Narbons (FR) and Varois (FR) planted with genetically modified maize expressing either the insecticidal Bacillus thuringiensis protein (Bt) or herbicide tolerance (HT), as described elsewhere in this volume, were analysed for nematodes, protozoa and microbial community structure. These analyses were mirrored in single-species testing and in mesocosm experiments, and were coordinated with field samples taken for microarthropods, enchytraeids and earthworms so allowing for cross-comparison and a better understanding of the results observed in the field. Over the first 2 years of the field experiments (in 2002 and 2003), the effect of Bt-maize was within the normal variation expected in these agricultural systems. Sampling in 2004 and 2005 was expanded to include the effects of tillage (i.e. reduced tillage versus conventional tillage) and also the use of HT-maize. Tillage had major effects regardless of soil type (Varois or Foulum), with reduced-tillage plots having a greater abundance of microfauna and a different microbial community structure (measured both by phospholipid fatty-acid analysis (PLFA) and by community-level physiological profiling (CLPP)) from conventionally titled plots. Grass, as a contrasting cropping system to maize, also had an effect regardless of soil type and resulted in greater microfaunal abundance and an altered microbial community structure. Differences in crop management, which for the Bt-maize was removal of the insecticide used to control European corn borer and for HT-maize was a change in herbicide formulation, were only tested at single sites. There were differences in microbial community structure (CLPP but not PLFA) and sporadic increases in protozoan abundance under the Bt-crop management. The HT-maize cropping system, which covered a shorter period and only one site, showed little change from the conventional system other than an altered microbial community structure (as measured by PLFA only) at the final harvest. The Bt-trait had a minimal impact, with fewer amoebae at Foulum in May 2003, fewer nematodes at Foulum in May 2004 but more protozoa at Varois in October 2002 and an altered microbial community structure (PLFA) at Foulum in August 2005. These were not persistent effects and could not be distinguished from varietal effects. Based on the field evaluations of microfauna and microorganisms, we conclude that there were no soil ecological consequences for these communities associated with the use of Bt- or HT-maize in place of conventional varieties. Other land management options, such as tillage, crop type and pest management regime, had significantly larger effects on the biology of the soil than the type of maize grown. (C) 2007 Elsevier GmbH. All rights reserved.

The effects of maize (Zea mays L.), genetically modified to express the CrylAb protein (Bt), and an insecticide on soil microbial and faunal communities were assessed in a glasshouse experiment. Soil for the experiment was taken from field sites where the same maize cultivars were grown to allow comparison between results under glasshouse conditions with those from field trials. Plants were grown in contrasting sandy loam and clay loam soils, half were sprayed with a pyrethroid insecticide (deltamethrin) and soil samples taken at the five-leaf stage, flowering, and maturity. The main effect on all measured parameters was that of soil type and there were no effects of Bt trait or insecticide on plant growth. The Bt trait resulted in more soil nematodes and protozoa (amoebae), whereas insecticide application increased plant Bt concentration and altered nematode community structure. The only significant effects on soil microbial community structure, microarthropods, and larvae of a nontarget root-feeding Dipteran, were due to soil type and plant growth stage. The results indicate that, although there were statistically significant effects of the Bt trait on soil populations, they were small. The relative magnitude of the effect could best be judged by comparison with the insecticide treatment, which was representative of current best practice. The Bt trait had no greater effect than the insecticide treatment. Results from this glasshouse experiment were in broad agreement with conclusions from field experiments using the same plant material grown in the same soils.

Under the umbrella of the International Organisation of Biological Control (IOBC), an international working group of public sector scientists entitled on “Transgenic Organisms in Integrated Pest Management and Biological Control” has been organized. The group will develop scientific principles and detailed scientific guidelines for biosafety testing of transgenic crops. The key elements of this project are: (1) An international initiative including expert scientists from leading research institutions in developed and developing countries; (2) coordination of the development and implementation of the guidelines as a dynamic process, which will include scientific and technical capacity building and communication among scientists and between scientists and policy makers; (3) rapid serial publication of sections of the guidelines as they are completed; and (4) rapid and timely revision of previously published sections. The guidelines will be constructed on a case-by-case basis and will have no regulatory legitimacy themselves.

A version of the Lotka-Volterra predator-prey model with logistic crop growth is modified to explore the rate of adaptation of a herbivore to a pest-resistant crop. This provides a phenotypic model for the evolution of resistance in a population comprising three different pest types each defined by differing parameter values for respiration rate and crop palatability. Expressions estimating the rates of increase of the fitter pest types are obtained as a function of the food qualities, and respiration and mortality rates. Potential strategies for delaying the rate of adaptation with regard to the expressions derived above, via the use of pest-susceptible refugia and natural enemies, are discussed. Although the model is formulated as one in which a single gene is the factor conferring resistance it can be interpreted and used independently of this.

Leaf-surface extracts prepared from 18 non-cultivated (wild) plant species, derived from the Capparidaceae, Cruciferae, Resedaceae and Tropaeolaceae were ranked for their ability to stimulate oviposition by the cabbage root fly, and analysed for glucosinolates. A total of 28 different glucosinolates were identified. A clear relationship was detected between the indolyl-, benzyl- and the total glucosinolate composition on the leaf surface and oviposition preference by cabbage root fly females. However, as the results are not fully explained by differences in leaf surface glucosinolates, other important oviposition deterrents and stimuli on the leaf surface of these wild crucifers must also be present.

Epicuticular waxes have been characterised from the flowers of raspberry and hawthorn, on both of which adult raspberry beetles ( Byturus tomentosus ) can feed. The flower wax from both species had similar alkane profiles and also contained long-chain alcohols, aldehydes and fatty acids. The range of the carbon numbers detected for these classes of compounds was broadly similar in both but the relative amounts of each differed between species. Raspberry flower wax also contained fatty acid methyl esters, a group of compounds that has rarely been detected in plant epicuticular waxes, however, these were not observed in hawthorn flower wax. Long-chain alcohol-fatty acid esters with carbon numbers ranging from C36 to C48 were also detected in both plant species. However, an examination of their constituent acids indicated that in hawthorn the esters based on the C16 fatty acid predominated, whilst in raspberry flower wax, esters based on the C20 fatty acid were most abundant. Both species also contained pentacyclic triterpenoids, which accounted for, on average, over 16 and 48% of the total wax extracted from raspberry and hawthorn flowers respectively. In the former, ursolic and oleanolic acids accounted for over 90% of the pentacyclic triterpenes, whilst hawthorn flower wax, in addition to containing these acids, also contained high relative concentrations of both free and esterified α- and β-amyrins.

Under the umbrella of the International Organisation of Biological Control (IOBC), an international working group of public sector scientists entitled on Transgenic Organisms in Integrated Pest Management and Biological Control has been organized. The group will develop scientific principles and detailed scientific guidelines for biosafety testing of transgenic crops. The key elements of this project are: (1) An international initiative including expert scientists from leading research institutions in developed and developing countries; (2) coordination of the development and implementation of the guidelines as a dynamic process, which will include scientific and technical capacity building and communication among scientists and between scientists and policy makers; (3) rapid serial publication of sections of the guidelines as they are completed; and (4) rapid and timely revision of previously published sections. The guidelines will be constructed on a case-by-case basis and will have no regulatory legitimacy themselves. Made available in DSpace on 2017-09-19T00:10:53Z (GMT). No. of bitstreams: 1 CapalboBrazil6377.pdf: 78816 bytes, checksum: 92443267ca790c0875b82a95d3ca13a7 (MD5) Previous issue date: 2006-09-28