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Background Edible insects are a nutritious and sustainable alternative source of animal proteins, and consequently are nowadays promoted as human food and animal feed worldwide. Ensuring the quality, safety, and traceability of insect foods is thus critical to maintain a safe and economically sustainable supply chain. Providing a simultaneous analysis of a wide range of chemical compounds, metabolomics and non-target screening (NTS) have become important mass spectrometry-based tools in the field of food sciences. At this moment, however, the application of these analytical techniques to edible insect-related topics has been largely overlooked. Scope and approach In this Commentary, we explore the potential of “entometabolomics” for food science and industry. We address the hurdles associated with safety, quality, and traceability of insects as food and feed and current issues related with insect industrial applications. Key findings and conclusions Current applications of metabolomics and NTS in traditional food systems are presented. We propose ways to translate and implement such techniques for the edible insect sector. Even if the broad applicability of metabolomics and NTS approaches is still hampered by technical challenges, we show the high potential of entometabolomics when implemented into the insect food and feed industry and research.

Insect farming for livestock feed has the potential to replace conventional feed

Over the last decade, the urgency to find alternative and sustainable protein sources has prompted an exponential increase in the interest in insects as a human food source. Edible insects contribute suitable amounts of energy and protein, fatty acids, and micronutrients to the human diet. Nutritional values of insects can be manipulated to meet specific needs. Edible insects in food-insecure countries can contribute to improving diets and preventing undernutrition. Bioactive compounds in insects may reduce health risks. Food safety risks are low and mainly relate to those of allergenicity. Strategies to overcome barriers to the consumption of insect products include emphasizing their sustainability, increasing their tastiness, and developing the ability to disguise insects in familiar products. A new sector of insects as food and feed is emerging. Major challenges include legislation, lowering prices by automation and cheap substrates, developing insect products that appeal to consumers, and exploring the health benefits. Expected final online publication date for the Annual Review of Nutrition, Volume 41 is September 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

This special issue presents the outcomes from “Designing sustainable and circular agricultural systems for the year 2100,” the joint scientific workshop of ISOFAR, the Thünen-Institute, and INRA-Morocco, which was held from November 14 to 16, 2019 in Marrakesh, Morocco. Nineteen scientists from a broad array of background and nationalities came together with the understanding that food security globally is at risk, especially in the post-2050 timeframe. Current concepts, strategies, measures, and scientific efforts carried out by governments, NGOs, businesses, and societies do not deliver satisfying solutions for how to sustainably produce enough healthy and affordable food to support the global population. With the economic and social impact of the Covid-19 pandemic in 2020, it became even more evident that food security is a challenge. This workshop took an innovative approach to addressing the challenges of future agriculture by considering sustainable, circular agricultural systems. Participants presented research results on algae-based food, edible insects, mushrooms, novel concepts for nutrient management, bioreactor-based farming, sustainable food culture, as well as sensor- and remote-controlled automatic food production. This special issue presents the papers contributed to the workshop and the results of the discussions.

An overview is given on recent developments in insects as food and food by reviewing the literature which has appeared during the last few years on edible insects. An outlook to the future is provided. About a decade ago, the attention shifted from harvesting insects in the tropics to farming insects all over the world for food and feed applications. Most production is targeted towards pet food, but it will turn to aquafeed in the next two decades. More than 80% of all publications dealing with edible insects appeared during the last five years. Crickets and mealworms are used for human food while the black soldier fly is the main species used as animal feed. The criteria to choose insect species are automation, cheap substrates, disease avoidance, and market potential. Genetics are increasingly explored to improve production. The environmental impact of producing insects compares well to other alternative proteins, in particular their capacity to degrade organic waste streams. Edible insects are not only a good source of nutrients but also seem to provide health benefits not only for humans and animals, but also for plants (left over substrate). The challenge of convincing Western consumers is reviewed and whether sustainability is an issue. Processing techniques are being developed. The sector of insects as food and feed is developing fast thanks to an increasingly conducive legislative framework. It will progress further, provided that the insect industry, academia, governmental organizations, and public society closely cooperate.

In the last 10 years, the interest to use insects as food and feed has increased exponentially. In tropical zones, insects are a common food item as they are more readily available as food in nature than in other climate zones. However, if we want to promote insects as food and feed, harvesting from nature is not an option and the farming of these animals is required. This can be done in environmentally controlled facilities. Insects are not only nutritionally excellent food; they may also have health benefits. When using organic side streams as substrate, chemical and biological contaminants need to be considered. People in western countries are not used to eating insects, and therefore, strategies to “convince” consumers of their hygienic safety, environmental sustainability, and tastiness are necessary. The insect sector is maturing fast, but still faces many challenges, which can only be met when all stakeholders cooperate closely.

Background: The order Hymenoptera has about 117,000 known species of which about 20.000 in the Afrotropical zone. The families covered are ants, bees, and wasps. They belong to the suborder Apocrita, characterized by a constriction between the first and second abdominal segments. The purpose of the study was to make an overview of how ants, bees and wasps and their products such as honey are utilized, perceived, and experienced in daily life across sub-Saharan Africa.Method: Ethno-entomological information on ants, bees and wasps in sub-Saharan Africa was collected by: (1) interviews with more than 300 people from about 120 ethnic groups in 27 countries in the region; (2) library studies in Africa, London, Paris and Leiden.Results : Of the order of the Hymenoptera only queens of the ant Carebara vidua are deliberately eaten. Often unintentionally bee larvae are eaten with honey and sugar ants with sugar. Apart from honey being a food item, it is also widely used to treat numerous medical problems, as a stimulant (for the memory) or as a cosmetic. It is also used in naming or wedding ceremonies. In the Qur’an, the medical value of honey is recognized. Seed stores of ants maybe harvested by humans. In the Sudan bee stings are used to cure arthritis; bee venom having bioactive properties. Wasp nests are used to cure inflammations such as mumps. The properties of certain insects are used to convey these treats to persons it is employed to, such as nasty stinging wasps to make dogs vicious. Some stories seem to make no sense like the snake-trapping ants in Madagascar, but a scientific explanation is provided. The looks of certain insects may inspire people to construct stories or have proverbs such as the very narrow waste of wasps, suggesting sterility. Bee swarms and driver ants are feared all over and believed to be employed (by witchdoctors) to punish. Not all stories of events with bees or ants are similar across sub-Saharan Africa. These insects, being social, are also used to stimulate cohesion between people.Conclusion: Ants, bees and wasps in sub-Saharan Africa maybe feared because of their bites and stings. However, the insects or their products are often employed for medical reasons, honey having numerous applications. They are also many stories and believes in which the characteristics of these insects play a role.

In Africa, about 470 insect species are recorded as edible, of which caterpillars are most consumed followed by grasshoppers, beetles, and termites. Most of those are collected from nature. There are several insect species, such as locusts and grasshoppers, that are pests of crops but which can be eaten at the same time. There are some edible insect species which are harvested in large number contributing to food security. Three of those species are discussed: the mopane caterpillar, the African bush cricket, and the shea caterpillar. However, when we would like to promote insects as food then harvesting from nature is not an option anymore, as overexploitation already occurs. Then we need to rear the insects. That can be done in semi-domesticated systems such as for the palm weevil or by farming insects as mini-livestock such as for crickets. We discuss the nutritional value of edible insects, and how they can contribute to food security. We also give examples of how insects can be processed and marketed. We conclude with the prospects of how edible insects can assure food security and improve the livelihood of the African people.

Population growth and unprecedented economic growth and urbanization, especially in low- and middle-income countries, coupled with extreme weather patterns, the high-environmental footprint of agricultural practices, and disposal-oriented waste management practices, require significant changes in the ways we produce food, feed and fuel, and manage enormous amounts of organic wastes. Farming insects such as the black soldier fly (BSF) (Hermetia illucens) on diverse organic wastes provides an opportunity for producing nutrient-rich animal feed, fuel, organic fertilizer, and biobased products with concurrent valorization of wastes. Inclusion of BSF larvae/pupae in the diets of poultry, fish, and swine has shown promise as a potential substitute of conventional feed ingredients such as soybean meal and fish meal. Moreover, the bioactive compounds such as antimicrobial peptides, medium chain fatty acids, and chitin and its derivatives present in BSF larvae/pupae, could also add values to the animal diets. However, to realize the full potential of BSF-based biorefining, more research and development efforts are necessary for scaling up the production and processing of BSF biomass using more mechanized and automated systems. More studies are also needed to ensure the safety of the BSF biomass grown on various organic wastes for animal feed (also food) and legalizing the feed application of BSF biomass to wider categories of animals. This critical review presents the current status of the BSF technology, identifies the research gaps, highlights the challenges towards industrial scale production, and provides future perspectives.

The article synthesises the experiences of innovation platforms (IPs) that engaged in open-ended experimental action to improve the institutional context for smallholder farm development in West Africa. The IPs sought change at the level of the institutional regime covering an entire agricultural domain (such as cocoa, cotton, oil palm or water management). Their purpose was therefore not to ‘roll out’ farm-level technologies across rural communities. The IPs's outcomes were documented and analysed throughout by means of theory-based process tracing in each of seven of the nine domains in which regime change was attempted. The evidence shows that by means of exploratory scoping and diagnosis, socio-technical and institutional experimentation, and guided facilitation IPs can remove, by-pass, or modify domain-specific institutional constraints and/or create new institutional conditions that allow smallholders to capture opportunity. The article describes the 5-year, €4.5 million research programme in Benin, Ghana and Mali, covering theory, design, methods and results. It is the sequel to Hounkonnou et al. in AGSY 108 (2012): 74–83.

In sub-Saharan Africa, urban populations are projected to increase by 115% in the coming 15 years. In addition, economic growth and dietary shifts towards animal source foods have put high pressure and demand on agricultural production. The high ecological footprint of meat and dairy production, as well as high feed costs, prevent the livestock sector from meeting the increasing demand in a sustainable manner. Insects such as the black soldier fly (BSF) have been identified as potential alternatives to the conventionally used protein sources in livestock feed due to their rich nutrient content and the fact that they can be reared on organic side streams. Substrates derived from organic byproducts are suitable for industrial large-scale production of insect meal. Although efficient in waste management and in feed production, BSF larvae are very sensitive to the external environment such as temperature and rearing medium. Therefore, we studied the effect of temperature and substrate type, i.e., brewers&rsquo, spent grain (SG) and cow dung (CD), on the development and survival of BSF larvae. Both organic substrates were readily available in Nairobi, Kenya, the location of the experiments. In our experiment, 100 3&ndash, 5-day-old BSF larvae were placed into containers that contained either SG or CD and further treated at temperatures of 15 &deg, C, 20 &deg, C, 25 &deg, C, 30 &deg, C, and 35 &deg, C. The duration of larval development was recorded, and the prepupae were removed, weighed, and placed individually in separate, labeled, 35-mL plastic cups filled with moist sawdust. After emergence, 10 2-day-old adults (5 males and 5 females) from every replica per substrate were transferred into a cage (40 &times, 40 &times, 40 cm) and allowed to mate for 24 h at their respective temperatures. The laid egg batches were collected and counted, and the adult flies&rsquo, longevity was recorded. The data were subjected to a two-way analysis of variance (ANOVA) using the general linear model procedure. BSF larvae reared on SG developed faster than those reared on CD, the former also favored higher temperatures for their larval development and emergence into adults. The optimum range was 25&ndash, 30 &deg, C. With increasing temperatures, the longevity of adult BSF decreased, while the fecundity of females increased. Thus, it is possible to take advantage of the readily available SG waste streams in the urban environments of Kenya to produce BSF larvae-derived livestock feed within a short duration of time and at relatively high temperatures.

In Africa, livestock production currently accounts for about 30% of the gross value of agricultural production. However, production is struggling to keep up with the demands of expanding human populations, the rise in urbanization and the associated shifts in diet habits. High costs of feed prevent the livestock sector from thriving and to meet the rising demand. Insects have been identified as potential alternatives to the conventionally used protein sources in livestock feed due to their rich nutrients content and the fact that they can be reared on organic side streams. Substrates derived from organic by-products are suitable for industrial large-scale production of insect meal. Thus, a holistic comparison of the nutritive value of Black Soldier Fly larvae (BSFL) reared on three different organic substrates, i.e. chicken manure (CM), brewers’ spent grain (SG) and kitchen waste (KW), was conducted. BSFL samples reared on every substrate were collected for chemical analysis after the feeding process. Five-hundred (500) neonatal BSFL were placed in 23 × 15 cm metallic trays on the respective substrates for a period of 3–4 weeks at 28 ± 2 °C and 65 ± 5% relative humidity. The larvae were harvested when the prepupal stage was reached using a 5 mm mesh size sieve. A sample of 200 grams prepupae was taken from each replicate and pooled for every substrate and then frozen at −20 °C for chemical analysis. Samples of BSFL and substrates were analyzed for dry matter (DM), crude protein (CP), ether extracts (EE), ash, acid detergent fibre (ADF), neutral detergent fibre (NDF), amino acids (AA), fatty acids (FA), vitamins, flavonoids, minerals and aflatoxins. The data were then subjected to analysis of variance (ANOVA) using general linear model procedure. BSFL differed in terms of nutrient composition depending on the organic substrates they were reared on. CP, EE, minerals, amino acids, ADF and NDF but not vitamins were affected by the different rearing substrates. BSFL fed on different substrates exhibited different accumulation patterns of minerals, with CM resulting in the largest turnover of minerals. Low concentrations of heavy metals (cadmium and lead) were detected in the BSFL, but no traces of aflatoxins were found. In conclusion, it is possible to take advantage of the readily available organic waste streams in Kenya to produce nutrient-rich BSFL-derived feed.

The global increase in demand for meat and the limited land area available prompt the search for alternative protein sources. Also the sustainability of meat production has been questioned. Edible insects as an alternative protein source for human food and animal feed are interesting in terms of low greenhouse gas emissions, high feed conversion efficiency, low land use, and their ability to transform low value organic side streams into high value protein products. More than 2000 insect species are eaten mainly in tropical regions. The role of edible insects in the livelihoods and nutrition of people in tropical countries is discussed, but this food source is threatened. In the Western world, there is an increasing interest in edible insects, and examples are given. Insects as feed, in particular as aquafeed, have a large potential. Edible insects have about the same protein content as conventional meat and more PUFA. They may also have some beneficial health effects. Edible insects need to be processed and turned into palatable dishes. Food safety may be affected by toxicity of insects, contamination with pathogens, spoilage during conservation and allergies. Consumer attitude is a major issue in the Western world and a number of strategies are proposed to encourage insect consumption. We discuss research pathways to make insects a viable sector in food and agriculture: an appropriate disciplinary focus, quantifying its importance, comparing its nutritional value to conventional protein sources, environmental benefits, safeguarding food safety, optimising farming, consumer acceptance and gastronomy.

Arthropods were an important food source for early hominids. They still are in tropical countries, where about 2000 species are consumed as a sustainable source of food, contributing to food security. Most species are harvested from nature depending on the season, and only some are semidomesticated or farmed. Throughout history local people have developed an intricate knowledge about these species which is reflected by the way how arthropods are harvested and prepared as food. Whether or not some arthropod species are eaten depends not only on taste and nutritional value but also on customs, ethnic preferences, or prohibitions. Its promotion deserves more attention both from national governments and development agencies.

A chicken manure management process was carried out through co-conversion of Hermetia illucens L. larvae (BSFL) with functional bacteria for producing larvae as feed stuff and organic fertilizer. Thirteen days co-conversion of 1000 kg of chicken manure inoculated with one million 6-day-old BSFL and 109 CFU Bacillus subtilis BSF-CL produced aging larvae, followed by eleven days of aerobic fermentation inoculated with the decomposing agent to maturity. 93.2 kg of fresh larvae were harvested from the B. subtilis BSF-CL-inoculated group, while the control group only harvested 80.4 kg of fresh larvae. Chicken manure reduction rate of the B. subtilis BSF-CL-inoculated group was 40.5%, while chicken manure reduction rate of the control group was 35.8%. The weight of BSFL increased by 15.9%, BSFL conversion rate increased by 12.7%, and chicken manure reduction rate increased by 13.4% compared to the control (no B. subtilis BSF-CL). The residue inoculated with decomposing agent had higher maturity (germination index >92%), compared with the no decomposing agent group (germination index ∼86%). The activity patterns of different enzymes further indicated that its production was more mature and stable than that of the no decomposing agent group. Physical and chemical production parameters showed that the residue inoculated with the decomposing agent was more suitable for organic fertilizer than the no decomposing agent group. Both, the co-conversion of chicken manure by BSFL with its synergistic bacteria and the aerobic fermentation with the decomposing agent required only 24 days. The results demonstrate that co-conversion process could shorten the processing time of chicken manure compared to traditional compost process. Gut bacteria could enhance manure conversion and manure reduction. We established efficient manure co-conversion process by black soldier fly and bacteria and harvest high value-added larvae mass and biofertilizer.

International audience; AbstractWith a growing world population, increasingly demanding consumers, and a limited amount of agricultural land, there is an urgent need to find alternatives to conventional meat products. Livestock production is, moreover, a leading cause of anthropogenic-induced climate change. To mediate this, more sustainable diets are needed, with reduced meat consumption or the use of alternative protein sources. Insects are promoted as human food and animal feed worldwide. In tropical countries, edible insects are harvested from nature, but overexploitation, habitat changes, and environmental contamination threaten this food resource. Therefore, sustainable harvesting practices need to be developed and implemented. We provide examples of (1) aquatic insects whose populations are threatened by pollution, (2) caterpillar species in Africa that are disappearing due to overexploitation and habitat change, (3) edible insects species that are considered pests in agro-ecosystems, and (4) edible insect species that can be conserved and enhanced in forest management systems. Insect farming can be conducted either on small-scale farms or in large-scale industrialized rearing facilities. We review the environmental sustainability of insect farming compared to livestock production. The major environmental advantages of insect farming compared to livestock production are as follows: (1) less land and water is required; (2) greenhouse gas emissions are lower; (3) insects have high feed conversion efficiencies; (4) insects can transform low-value organic by-products into high-quality food or feed; and (5) certain insect species can be used as animal feed or aqua feed. For instance, they can replace fish meal, which is becoming increasingly scarce and expensive. However, edible insect species intended for production should be screened for risks to humans, animals, plants, and biodiversity.

In the present study, the synergistic effects of Beauveria bassiana (Bals.-Criv. Vuill.) (isolate Bb11) and Bacillus thuringiensis var. kurstaki (Berliner) with neem oil were evaluated in three agroecological zones in Be´nin. Four bioinsecticide treatments (neem oil, neem oil and B. bassiana used separately for different target pests, neem oil mixed with B. bassiana and neem oil mixed with B. thuringiensis) were compared with a calendar-based treatment using synthetic insecticides and a control without insecticides. The bioinsecticide treatments were less effective than the calendar-based treatment at controlling cotton pests. There was no difference in yields and the number of damaged bolls in plots under treatments with the four bioinsecticide formulations, suggesting an absence of synergy between neem oil and B. bassiana and neem oil and B. thuringiensis. The numbers of natural enemies in all the bioinsecticide treatment plots and the control plots were similar and higher than those in the calendar-based treatment plots. The highest yield and profitability were obtained with the calendar-based treatment. Screening the compatibility of plant-based products and biopesticides through bioassays is essential for a successful application of their combinations in any integrated pest management strategy.

A large part of the environmental impact of animal production systems is due to the production of feed. Insects are suggested to efficiently convert feed to body mass and might therefore form a more sustainable food and/or feed source. Four diets were composed from by-products of food manufacturing and formulated such as to vary in protein and fat content. These were offered to newly hatched Argentinean cockroaches, black soldier flies, yellow mealworms, and house crickets. The first two species are potentially interesting as a feed ingredient, while the latter two are considered edible for humans. Feed conversion efficiency, survival, development time, as well as chemical composition (nitrogen, phosphorus, and fatty acids), were determined. The Argentinean cockroaches and the black soldier flies converted feed more efficiently than yellow mealworms, and house crickets. The first two were also more efficient than conventional production animals. On three of the four diets yellow mealworms and house crickets had a feed conversion efficiency similar to pigs. Furthermore, on the most suitable diet, they converted their feed as efficiently as poultry, when corrected for edible portion. All four species had a higher nitrogen-efficiency than conventional production animals, when corrected for edible portion. Offering carrots to yellow mealworms increased dry matter- and nitrogen-efficiency and decreased development time. Diet affected survival in all species but black soldier flies, and development time was strongly influenced in all four species. The chemical composition of Argentinean cockroaches was highly variable between diets, for black soldier flies it remained similar. The investigated species can be considered efficient production animals when suitable diets are provided. Hence, they could form a sustainable alternative to conventional production animals as a source of feed or food.

With a growing world population and increasingly demanding consumers, the production of sufficient protein from livestock, poultry, and fish represents a serious challenge for the future. Approximately 1,900 insect species are eaten worldwide, mainly in developing countries. They constitute quality food and feed, have high feed conversion ratios, and emit low levels of greenhouse gases. Some insect species can be grown on organic side streams, reducing environmental contamination and transforming waste into high-protein feed that can replace increasingly more expensive compound feed ingredients, such as fish meal. This requires the development of cost-effective, automated mass-rearing facilities that provide a reliable, stable, and safe product. In the tropics, sustainable harvesting needs to be assured and rearing practices promoted, and in general, the food resource needs to be revalorized. In the Western world, consumer acceptability will relate to pricing, perceived environmental benefits, and the development of tasty insect-derived protein products.

Innovation as a policy goal, normative practice, and a conceptual framing of purposeful human activity, has received increasing attention. The question of what kinds of purposeful innovation might benefit smallholders in developing countries has been raised. This issue presents and analyses the work of Innovation Platforms (IPs) established by the COS-SIS (Convergence of Sciences–Strengthening Innovation Systems) programme in nine agro-enterprise domains in West Africa, drawing on Theory Guided Process Inquiry data recorded through 2011-end 2013. Six papers synthesise individual IP experiences, complemented by a cross-case analysis of external influences on the IPs and their responses, a reflection on how well the IPs in Mali dealt with local conflicts, and an analysis of how the work of the IPs in Ghana led to changes in university curricula and in the researching practices of three leading agricultural institutes. An analysis of thirteen case studies from Kenya, Benin, and South Africa supported by the JOLISAA (Joint learning in and about Innovation Systems in African Agriculture) programme, adds further insights. Five general lessons are drawn, expressed as propositions that can be further tested against others’ experiences: (i) IPs can bring about significant socio-technical and institutional changes at a range of levels, and in a wide variety of agro-enterprise domains and contexts; (ii) the IPs are not isolated from nor independent of the networks of influence in which they are embedded; thus they cannot be treated as the sole causal agents of the changes accomplished; (iii) research that tracks the IPs’ work and performance provides evidence that enables the members to learn from experience and adjust activities in the light of effects; (iv) there is no blueprint for what an IP is nor a recipe for the processes by which such changes are brought about; the form, activities, and changes co-evolve with whatever is happening in the wider context; (v) field-based diagnosis of opportunity, evidence-based information-sharing and experimental exploration of pathways of change establish the legitimacy and influence of IPs.

The effect of four host plant species of the herbivore Maruca vitrata Fabricius (Lepidoptera: Crambidae) on development time, longevity, fecundity and sex ratio of the parasitoid Apanteles taragamae Viereck (Hymenoptera: Braconidae) was investigated under laboratory conditions. The larvae were parasitized when in the second instar. Maruca vitrata larvae were fed with flowers of four legumes, that is, Vigna unguiculata (cowpea), Sesbania rostrata, Lonchocarpus sericeus and Pterocarpus santalinoides, or an artificial diet both before and after parasitization. The parasitoid did not develop in hosts feeding on L. sericeus or V. unguiculata at 25°C, or on P. santalinoides at 25°C or 29°C. Apanteles taragamae had the shortest development time on artificial diet at both 25°C and 29°C while the longest development time was recorded on L. sericeus at 29°C. Female wasps took longer to develop compared to males at the two temperatures, regardless of the feeding substrate of their host. The longevity of the wasps at 25°C varied among feeding substrates, but not at 29°C. Survival rate of parasitized larvae depends on the feeding substrate. Moreover, infection of host larvae with Maruca vitrata multi-nucleopolyhedrovirus (MaviMNPV) killed larger proportions of parasitized larvae at 25°C than at 29°C, which was likely caused by the difference in parasitoid developmental rate. The proportion of female parasitoids was lowest on L. sericeus. The daily fecundity showed a nonlinear trend regardless of the feeding substrate, indicating that A. taragamae is a pro-ovigenic species. The data support the slow growth–high mortality hypothesis.

Apanteles taragamae Viereck is a larval parasitoid introduced in Benin for classical biological control of the cowpea pod borer Maruca vitrata Fabricius. In the laboratory, we evaluated the effects of A. taragamae on non-target herbivore species, and on another parasitoid of M. vitrata, i.e. the egg-larval parasitoid Phanerotoma leucobasis Kriechbaumer. Furthermore, we addressed the host feeding behaviour of A. taragamae. The host specificity of A. taragamae was assessed by offering six other lepidopteran species to the wasp. The competitive ability of A. taragamae was studied by providing the wasp with one- and two-days-old M. vitrata larvae that had hatched from eggs previously parasitized by P. leucobasis. Controls consisted of eggs and larvae offered only to P. leucobasis and A. taragamae, respectively. None of the other six lepidopteran species was successfully parasitized by A. taragamae. The larval parasitoid A. taragamae outcompeted the egg-larval parasitoid P. leucobasis when offered two-days-old host larvae. Competition between the two parasitoid species did not significantly affect one-day-old host larvae that were less suitable to A. taragamae. Host feeding by A. taragamae did not affect survival of one-day-old or two-days-old M. vitrata larvae. However, the percentage parasitism of two-days-old larvae was significantly reduced when exposed to female A. taragamae wasps that had been starved during 48 h. The data are discussed with regard to host specificity, host feeding patterns and to factors underlying the outcome of intrinsic competition between parasitoid species.

Because of growing demand for meat and declining availability of agricultural land, there is an urgent need to find alternative protein sources. Edible insects can be produced with less environmental impact than livestock. Insect meal can replace scarce fishmeal as feed ingredient, in particular in the fast growing aquaculture industry. Edible insects can alleviate waste disposal problems by growing them on organic by-products. About 2000 insect species are eaten worldwide, mostly in tropical countries. They have adequate protein quantity and quality and high content of unsaturated fatty acids and minerals like iron and zinc. Promotion of insects as food and feed will require the insects to be farmed. In tropical countries this is done small-scale, but in particular for use of insects as feed, production is needed in large automated industrial facilities. Food safety problems relate to contamination with pathogens, requiring hygienic farming. Proper labelling may be required for people allergic to seafood and house dust mites as cross reactivity may occur. Western consumers are hard to convince to eat insects, even when aware of environmental, nutritional and food safety benefits and their excellent taste. Emotional and psychological impediments to acceptance have to be addressed. The way forward of edible insects to become a new sector in agriculture and the food and feed industry is discussed. In particular, legislation lags behind developments and needs to be addressed urgently.

The parasitoid wasp Apanteles taragamae is a promising candidate for the biological control of the legume pod borer Maruca vitrata, which recently has been introduced into Benin. The effects of volatiles from cowpea and peabush flowers and Maruca vitrata larvae on host selection behavior of the parasitoid Apanteles taragamae were investigated under laboratory conditions by using a Y-tube olfactometer. Naïve and oviposition-experienced female wasps were given a choice between several odor sources that included (1) uninfested, (2) Maruca vitrata-infested, and (3) mechanically damaged cowpea flowers, as well as (4) stem portions of peabush plants carrying leaves and flowers, (5) healthy M. vitrata larvae, and moribund (6), and live (7) virus-infected M. vitrata larvae. Responses of naïve and oviposition-experienced female wasps did not differ for any of the odor source combinations. Wasps were significantly attracted to floral volatiles produced by cowpea flowers that had been infested with M. vitrata larvae and from which the larvae had been removed. Apanteles taragamae females also were attracted to Maruca vitrata-infested flowers after removal of both the larvae and their feces. Female wasps discriminated between volatiles from previously infested flowers and mechanically damaged flowers. Uninfested cowpea flowers attracted only oviposition-experienced wasps that had received a rewarding experience (i.e. the parasitization of two M. vitrata larvae feeding on cowpea flowers) before the olfactometer test. Wasps also were attracted to uninfested leaves and flowers of peabush. Moreover, they were also attracted to healthy and live virus-infected M. vitrata larvae, but not when the latter were moribund. Our data show that, similarly to what has been extensively been reported for foliar volatiles, flowers of plants also emit parasitoid-attracting volatiles in response to being infested with an herbivore.

1. The desert locust is a migratory pest whose population development in remote areas must be monitored to prevent outbreaks, upsurges and plagues. Monitoring would be very much facilitated if the area of search could be restricted to sites of likely population increase. 2. The spatial distribution of solitarious desert locusts on the Red Sea coastal plain of Sudan was determined over 3 years from November to March. Additional observations were made on habitat factors, such as plant community, soil texture, soil moisture and land use. 3. Locust densities varied according to the amount and distribution of rainfall and longevity of the annual green vegetation, with virtually no locusts being observed in the driest season. 4. Samples on a grid of 120 sites within a 120-km stretch of coastal plain showed that locusts were prevalent only in the millet-Heliotropium plant community, which is found at sites with a fine sandy soil texture and comparatively high and long-lasting soil moisture in wadi deltas. These sites constitute less than 5% of the area of this part of the plain. 5. An accessory study showed association between desert locust distribution and millet cropping in an area where no Heliotropium was found. Other samples confirmed the association between solitarious desert locust and millet agriculture. 6. Synthesis and applications. The results indicate that surveys for early detection and control of desert locust on the Red Sea coast of Sudan can focus on millet cropping areas. The results suggest that the efficiency of monitoring migratory pest outbreaks in remote areas could be enhanced by using associations between plant communities and herbivorous insects to predict risk areas and target survey efforts.

Plant products were evaluated under field conditions for their efficacy as insecticides against the cowpea beetle, Callosobruchus maculatus, on stored cowpea. Seeds, mixed with finely ground clay and three volatile oils were stored in air-tight jerry-cans and canisters. Pods were treated with leaf powders of two plant species and stored in traditional palm-leaf huts. Beetle damage was evaluated before and after storage. The treatments did not prevent damage, but after treatment with oils, fewer beans showed beetle emergence holes; also, the percentage of uninfested beans and the weight of one litre of beans were each higher than for untreated beans. The percentage of germination of stored beans was highest after treatment with Ocimum basilicum oil. Leaf powder of Momordica charantia was effective against weight loss of stored seeds, whereas Ficus exasperata caused a decrease in both the percentage of infested beans and the number of emerged beetles, and more parasitoids emerged than from untreated beans. Laboratory tests on the effect of the oils on the development of the beetle and on bean germination did not reveal effects of the oils. We compare data obtained from the laboratory and with those obtained in the field.

Three different bioassay methods to investigate the orientation behaviour of the banana weevil, Cosmopolites sordidus (Germar) (Coleoptera: Curculionidae), to host plant volatiles and a synthetic pheromone (cosmolure+) were compared. A locomotion compensator was used to separately record walking tracks in response to three odour sources. The data show that C. sordidus uses odour-conditioned anemotaxis in its orientation to the odour sources tested. Of the two olfactometers tested, a dual port olfactometer using a continuous airflow showed stronger discrimination by C. sordidus to the different odours compared with a double pitfall olfactometer. The results of all three bioassays indicate that C. sordidus responds in an additive way to the combination of fermentation plant volatiles and the synthetic pheromone.

Infochemicals play an important role in the biology of many insect species. An understanding of their role in plant-herbivore-carnivore interactions can be used in the development of tools for the enhancement of environmentally benign alternatives to synthetic pesticides. This review discusses how chemical information mediates ecological interactions between organisms and the role of infochemicals in integrated pest management. Infochemicals can be used in pest monitoring and in pest control, through mating disruption, mass trapping and to aggregate herbivores at delivery sites for biological control agents. Particular emphasis is placed on the potential of using pheromones and kairomones in the management of the banana weevil, Cosmopolites sordidus (Germar) (Coleoptera: Curculionidae), a pest in plantations of East African highland banana and plantain in most banana-growing regions of the world. Cosmopolites sordidus produces an aggregation pheromone that attracts both males and females. This pheromone has been identified and synthesised and is being recommended as an effective agent in the trapping and control of the weevil. The synergism between banana plant extracts (kairomones) and the synthetic pheromone in attracting C. sordidus should be better exploited. Future research areas that can provide information for the development of an infochemical-based trapping system for the management of C. sordidus are discussed.

Insects receive increasing attention as an alternative protein-rich food source for humans. Producing edible insects on diets composed of organic by-products could increase sustainability. In addition, insect growth rate and body composition, and hence nutritional quality, can be altered by diet. Three edible mealworm species Tenebrio molitor L., Zophobas atratus Fab. and Alphitobius diaperinus Panzer were grown on diets composed of organic by-products originating from beer brewing, bread/cookie baking, potato processing and bioethanol production. Experimental diets differed with respect to protein and starch content. Larval growth and survival was monitored. Moreover, effects of dietary composition on feed conversion efficiency and mealworm crude protein and fatty acid profile were assessed. Diet affected mealworm development and feed conversion efficiency such that diets high in yeast-derived protein appear favourable, compared to diets used by commercial breeders, with respect to shortening larval development time, reducing mortality and increasing weight gain. Diet also affected the chemical composition of mealworms. Larval protein content was stable on diets that differed 2–3-fold in protein content, whereas dietary fat did have an effect on larval fat content and fatty acid profile. However, larval fatty acid profile did not necessarily follow the same trend as dietary fatty acid composition. Diets that allowed for fast larval growth and low mortality in this study led to a comparable or less favourable n6/n3 fatty acid ratio compared to control diets used by commercial breeders. In conclusion, the mealworm species used in this study can be grown successfully on diets composed of organic by-products. Diet composition did not influence larval protein content, but did alter larval fat composition to a certain extent.