Classical and augmentative biological control of insect pests and weeds has enjoyed a long history of successes. However, biocontrol practices have not been as universally accepted or optimally utilised as they could be. An International Organisation for Biological Control (IOBC) initiative brought together practitioners and researchers from widely diverse fields to identify the main limitations to biocontrol uptake and to recommend means of mitigation. Limitations to uptake included: risk averse and unwieldy regulatory processes; increasingly bureaucratic barriers to access to biocontrol agents; insufficient engagement and communication with the public, stakeholders, growers and politicians of the considerable economic benefits of biocontrol; and fragmentation of biocontrol sub-disciplines. In this contribution we summarise a range of recommendations for the future that emphasise the need for improved communication of economic, environmental and social successes and benefits of biological control for insect pests, weeds and plant diseases, targeting political, regulatory, grower/land manager and other stakeholder interests. Political initiatives in some countries which augur well for biocontrol in the future are discussed.

Quality assessment of entomophagous arthropods used in augmentative biological control is one of the main concerns after their mass production. The quality-testing procedures for natural enemies reared on artificial diets largely remain to be defined. As a first approach, comparisons of some relevant parameters between in vivo- and in vitro-reared entomophages are presented in this chapter. Results from experiments with different kinds of diets with or without insect components, developed for parasitoids and predators, are examined. Morphological traits as well as development and reproduction parameters used for comparisons between in vivo- and in vitro-grown arthropods are discussed. Morphological characters include body size and weight and the occurrence of abnormalities. Immature development is assessed by measuring duration and survival rates of the different stages. Sex ratio and symbiont association, fecundity-fertility and longevity are compared as reproduction parameters. It is important to consider biochemical parameters, such as protein, lipid and carbohydrate content, for quality control. These parameters may also indicate the deficiency or excess in a particular nutritional component. Behavioural and genetic parameters are considered as well. The establishment of relationships between certain parameters, e.g. between body size and fecundity or longevity, may help in simplifying quality control procedures. The ultimate quality criterion for an artificially reared natural enemy is its capacity to reduce pest populations, which can be evaluated by measuring the predation efficiency or the parasitization rate under laboratory or field conditions.

Potentially, the introduction of exotic natural enemies or mass release of biological control agents may lead to unwanted non-target effects. Whether or not such effects occur will depend mainly upon the host range of the biological control agent and the presence of non-target species in the areas of release and dispersal. To predict non-target effects, risk assessments for release of exotic natural enemies have been developed and applied during the modern era of biological control. Although methods to determine host ranges of natural enemies have been proposed during the past decades, decisions about release of exotic natural enemies are often still based on short-term decisions strongly influenced by financial benefit and tend to ignore environmental ethics, especially where risks are difficult to quantify. Here, we propose a framework for host-range testing of arthropod biological control agents, and suggest methods for evaluating possible effects on those non-target species considered to be at risk. Several factors should be incorporated into a host-range assessment, including literature and museum records, field observations in the area of origin, as well as physiological, behavioural and ecological observations and experiments. Usually, laboratory-based manipulative experiments will form the core of host-range assessments. In this chapter we concentrate on the question of how to determine host ranges. Several important considerations involved in designing host-range testing are presented. Next, a framework for step-wise host-range testing is given with levels of increasing complexity that should allow over- and underestimation of the host range of a biological control agent to be avoided. Finally, the interpretation of data obtained with host-range testing is discussed and conclusions are drawn about the importance of host-range testing within the framework of future biological control projects.

A 4-year research project on 'Evaluating Environmental Risks of Biocontrol Introductions in Europe' (ERBIC) is described, and early results are presented. The project focuses on arthropod biological control (using both microbial and macrobial agents), and uses literature review, case studies with empirical work and various types of modelling to illuminate risk to non-target organisms. These methods will hopefully lead to the development of usable methodologies and guidelines for risk assessment in arthropod biological control, by the project's completion in 2002. Reviewing existing published and unpublished data on the classical biological control of insects (a first step in this project) has revealed that for only 1.5% of introductions is there some data regarding the realized field specificity of the agent. For a tiny proportion of introductions there are quantitative data regarding mortality in non-targets. From these cases, with some extrapolation, we can deduce that 10% or less of classical biological control introductions in the past led to population changes in non-targets. Data on population-level effects from simulated uses or trials suggest that 49% of inundative or augmentative uses of agents led to (local, short-term) population changes for non-targets. Case studies into: (i) exotic specialist parasitoids used in the greenhouse; (ii) exotic generalist parasitoids used inundatively in the field; (iii) exotic generalist predators used inundatively; and (iv) fungi and nematodes used as bioinsecticides, are outlined. The results so far demonstrate: (i) the apparent safety of Trichogramma (generalist parasitoid) releases in Switzerland, despite rare species within its host range; (ii) the lack of overwintering capability in northern Italy in one generalist predator (Orius insidiosis), but its presence in another (Harmonia axyridis); (iii) little evidence that the predation of certain stages of native predators by introduced predators will enhance environmental risks in the cases in question; and (iv) the apparent safety of bioinsecticide releases of particular pathogen strains for important naturally occurring predators when exposed directly or by feeding on infected prey.

Several international documents have been published in recent years with the objective of providing guidance to industry, biocontrol practitioners and competent national regulatory authoritieson the regulatory framework for the import and release of invertebrate biological control agents(IBCAs). As the scope and the level of detail given in these documents were diverse in many respects, it has been difficult for all stakeholders to apply such guidelines, and to integrate them in a harmonized way into national regulatory documents. At the request of several stakeholders, the International Organization for Biological Control of Noxious Animals and Plants/West Palaearctic Regional Section (IOBC/WPRS) organized an initiative with the objective of merging all relevant international documents into one document, to provide more specific guidance, and to harmonizethe regulation of IBCAs in European countries and in other countries of the IOBC/WPRS. This document consists of five sections which together form comprehensive guidelines specifying the information required for regulating import and release of IBCAs.

Host-plant and whitefly strain effects and their interactions on the probing and sap feeding of the greenhouse whitefly, Trialeurodes vaporariorum (Westwood), have been investigated in this study using the DC-EPG (Electrical Penetration Graph) technique. Whiteflies generally displayed fewer but longer probes on highly acceptable cucumber than on less acceptable tomato. Both whitefly strains, the T(omato)-strain and the C(ucumber)-strain, showed a significantly lower number of phloem phases on cucumber than on tomato. However, the duration of total phloem phases achieved by either of the whitefly strains on these two host plants was not significantly different. These data indicate that a more continuous phloem feeding has occurred on cucumber plants. Indeed, the percentage of phloem feeding time after the first sustained phloem phase (longer than 15 min) was higher on cucumber for the C-strain whiteflies. When comparing these two whitefly strains, the T-strain whiteflies probed less frequently but longer than the C-strain whiteflies did on both host plants. Also, the T-strain whiteflies displayed a longer duration of total phloem phases on tomato. An interaction between the whitefly strain and plant effects was detected on a parameter, which showed that whiteflies probed significantly longer before reaching the first phloem phase on the host plants that had been previously experienced. In conclusion, both plant species and whitefly strains affect whitefly's probing and feeding behaviour, though plant effects are much stronger.

The Panel on Plant Health conducted a pest risk assessment for Bemisia tabaci and the viruses it transmits, including an evaluation of risk reduction options and an assessment of the effectiveness of the special requirements linked to B. tabaci and the viruses listed in Council Directive 2000/29/EC. B. tabaci and a large number of viruses transmitted by this polyphagous insect occur in subtropical and tropical climates around the world. Five entry pathways for B. tabaci and associated viruses were identified, with the plants for planting pathway being most significant and rated for entry of insects and viruses as likely and moderately likely, respectively. The most invasive B. tabaci species and several of its associated viruses responsible for severe diseases in major European food crops are established outdoors in coastal Mediterranean regions. Because of similar climate requirements and host plant preferences, B. tabaci and associated viruses currently not present in Europe are likely to establish within the temperature limits set for B. tabaci. Trade between European Member States allows B. tabaci to reach greenhouses in northern Europe, including those in areas with protected zone status. Because of the cool climate, establishment and spread outdoors of B. tabaci is rated unlikely for northern Europe. This situation is likely to continue even under a climatic scenario with an increase in temperature of +2 °C. B. tabaci -transmitted viruses cause severe diseases with major negative impact on crop production when risk reduction measures are not used. Risk reduction options will also apply to B. tabaci and viruses new to Europe. Risk reductions options are evaluated in terms of reducing B. tabaci populations, crop infestations, virus incidence and the impact of diseases. © European Food Safety Authority, 2013 KEY WORDSBemisia tabaci, European and non-European Bemisia tabaci, begomoviruses, non-circulatively transmitted viruses, pest risk assessment, risk reduction options. With regard to the assessment of the risks to plant health:B. tabaci is considered to be one of the most serious threats to crop cultivation worldwide, predominantly because of the large number of viruses it transmits. In regions where B. tabaci is established, viruses transmitted by this insect, especially those affecting tomato and cucurbits, and also beans, pepper and aubergines, are responsible for severe diseases that have a strong negative impact on crop yield. As a consequence, crop production in those areas is not possible without a system-wide and comprehensive set of pest and disease management measures in place. In the risk assessment area, B. tabaci is present outdoors in coastal areas with a Mediterranean climate, and in many EU countries the pest is present in greenhouses.B. tabaci is a complex of at least 28 indistinguishable morphocryptic species, of which four occur in Europe. Two species, Mediterranean (Med, formerly referred to as biotype Q) and Middle East-Asia Minor 1 (MEAM1, formerly referred to as biotype B), a...

The commercial use of biological control has seen a very fast development during the past 30 years. Currently, about 85 companies worldwide produce more than 125 species of natural enemies. The largest variety of commercially produced species of natural enemies is available in Europe, mainly as a result of a much larger greenhouse industry in Europe, although many species are also available in North America. Emerging markets are Latin America, Asia and (South) Africa. The most commonly sold natural enemies are discussed in this chapter. The recommended release rates, the unit of sale and the target pest(s) are specified. In addition, a list of the commercially available biocontrol agents is provided, together with the target pests and the year of first use.