Fruit fly identification, population dynamics and fruit damage during fruiting seasons of sweet oranges in Rusitu Valley, Zimbabwe

In 2003, the pest species Bactrocera dorsalis (Hendel) was reported for the first time in Kenya, Africa, and subsequently on many other African countries. In this work, 20 locations along the Rusitu Valley (Zimbabwe) were sampled in 2014 during the sweet oranges fruiting seasons, to verify the fruit fly taxonomy, invasion source, population dynamics, and fruit damage. The trapped fruit flies were identified using morphological traits and molecular techniques, as B. dorsalis. The haplotype network analysis revealed that Zimbabwe COI sequences were identical to other African B. dorsalis sequences. Fruit fly trappings per day varied during the year, although it remained always high. The same applies to fruit damage, most likely due to the permanent availability of cultivated and wild fruit varieties during the year. Rusitu Valley was invaded by B. dorsalis, most likely from neighbouring countries. Ten years after the first report in Kenya, the complete or near complete invasion of Africa has been achieved by B. dorsalis. In northern Africa the distribution is clearly limited by the Sahara desert. The large population size, the polyphagous nature of the species, and the continuous availability of suitable host fruit species during the year complicates the eradication of this species.The authors would like to thank the project Norte-01-0145-FEDER-000008-Porto Neurosciences and Neurologic Disease Research Initiative at I3S, supported by Norte Portugal Regional Operational Programme (NORTE2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (FEDER) for financing this work. Fruit fly trapping and data collection was financed by the Chinhoyi University of Technology under the Postgraduate Grant PG4001. Travel and stay at the University of Porto was financed by Erasmus Mundus Dream project, Action 2 - STRAND 1, Lot 18, ACP Countries, Master Mobility Scholarship

Host plant effects on morphometric characteristics of Liriomyza huidobrensis, L. sativae and L. trifolii (Diptera: Agromyzidae)

Body size of herbivorous insects may be directly related to host plant characteristics (e.g. nutrition, chemical composition) and positively linked to performance of the herbivore and its parasitoids. Differences in adult body size of Liriomyza huidobrensis, L. sativae and L. trifolii reared on Pisum sativum, Phaseolus vulgaris, Vicia faba and Solanum ycopersicum were assessed to determine the effect of host plants on adult size. Furthermore, morphometric wing and hind tibia measurements were used to determine suitability as proxy measures for adult size. Based on canonical and linear discriminant analyses, two distinct Liriomyza morphospecies groups were recognized across all plant species. The first cluster represented L. huidobrensis and the second L. sativae and L. trifolii. The overall degree of correct classification of the three species across all plants tested (correct observation) with cross validation was estimated at 85%. Liriomyza huidobrensis, the largest species, showed no differences in the variables measured when reared on the four plant species. However, different plant species seem to influence wing and hind tibia measurements in L. trifolii to a greater extent than in L. huidobrensis and L. sativae. The first two canonical variates could not separate the populations of L. huidobrensis and L. sativae reared on different plant species, but showed separation of L. trifolii populations into two clusters: firstly, insects reared on V. faba and secondly, insects reared on P. vulgaris and S. lycopersicum. Hind tibia length strongly correlated with wing length. Both can be used to determine adult size of the three Liriomyza species. This study provides some new evidence for the existence of differential preferences by Liriomyza species for the four host plant species. This, therefore, warrants larger scale field studies to test for positive preference- performance of Liriomyza species on these plant species and to determine possible consequences at the third tritrophic level

Nutrient and anti-nutrient composition of Henicus whellani (Orthoptera: Stenopelmatidae), an edible ground cricket, in south-eastern Zimbabwe

The purpose of this study was to investigate nutritional and phytochemical composition of Henicus whellani Chopard, a seasonally occurring ground-dwelling cricket consumed in south-eastern Zimbabwe. Insects were sampled from four quadrants (approximately 100m2) in one representative site (approximately 3000m2) in Bikita District, and were hand-picked or dug out from burrows in a manner similar to traditional insect-harvesting practices. Proximate composition using whole-dried insects and bioactive components using dried pulverized material were analysed using standard procedures. The proportional nutrient composition was 53.6% crude protein, 4.3% fat, 13.4% ash, 10.6% crude fibre, 4.0% carbohydrate and 268.3 kcal/100 g energy. Phenolics, tannins, alkaloids, cyanogenic glycosides, oxalates, saponins and flavonoids were present in the extracts of insects. The quantities of saponins (53.3 mg/g) and alkaloids (52.3mg/g) were higher than those of other phytochemicals, with the quantity of tannins (0.168 mg/g) being the lowest. Radical-scavenging capacity determined using di(phenyl)-(2,4, 6-trinitrophenyl)iminoazanium (or 2,2-diphenylpicrylhydrazyl) and methanol extracts was 42%, which is lower than those of the standards. This study shows that H. whellani provides potential nutritional benefits in terms of protein, fibre and flavonoid contents. The relatively high ash content compared with that from other edible insects indicates a rich source of minerals such as calcium, iron, magnesium, phosphorus and potassium. However, the presence of saponins, oxalates and tannins could be a limitation and requires further studies. There is a need to evaluate the bioaccessibility of the nutrients and the safety of bioactive compounds in relation to human consumption

<b>Effects of post-harvesting practices on heavy metal levels of mopane caterpillar (</b><b><i>Gonimbrasia belina</i></b><b>) products and associated risk assessment</b>

Mopane caterpillars (Gonimbrasia belina) are one of the most consumed edible insects in Southern Africa, and they contribute nutritional benefits to human health. However, their contribution to the food and nutritional security can be hindered by food safety concerns due to heavy metal contamination associated with harvesting, processing and poor post-harvest practices. This study investigated the effectiveness of post-harvest practices (degutting, charcoal roasting and sun drying, boiling, frying and open pan roasting) in reducing the heavy metal contaminants (cadmium (Cd), mercury (Hg), lead (Pb), nickel (Ni), aluminium (Al), zinc (Zn), copper (Cu) and iron (Fe)) in mopane caterpillar sourced from Gwanda district in Zimbabwe. The post-harvest practice categories used in this study included: unprocessed (ungutted and naturally degutted samples), processed (manually degutted, and charcoal roasted and sun-dried), and cooked (boiled and salted; boiled, salted and roasted, and boiled, salted and fried) samples. An atomic absorption spectrometry (AAS) was used for quantification of metals and the values detected were used to assess health risks to consumers using a quantitative risk assessment calculation method. The unprocessed and manually degutted samples showed higher levels Cd and traces of Pb, while charcoal roasting and sun drying resulted in elevated levels of Al, Zn, Cu and Fe. Hg and Ni were not detected in any of the unprocessed, processed or cooked samples. Cooking processes resulted in reduction of the concentrations of detected metals to levels within the permissible values. The health risk assessment disclosed noncarcinogenic risks based on the high hazard index (HI) values (HI > 1) in unprocessed, processed, boiled and salted, and boiled, salted and roasted samples, indicating that caution should be taken. The overall findings from the study shows that by cooking mopane caterpillars through boiling and frying, health risks associated with heavy metal contamination can be reduced.</p

Edible insect value chains in Africa

This special issue was organised in the context of the 22nd meeting of the Association of African Insect Scientists (AAIS), in Wad Medani, Sudan in 2017. The aim was to ‘support impactful research that will yield genuine edible insects products and sustain value chains that enhance food and nutritional security and support sustained livelihoods in Africa’. The issue is composed of contributions from the following countries: Kenya, Uganda, Burundi, Nigeria, Mali, Burkina Faso, Cameroon, Malawi, and Zimbabwe. The issue attempted to strengthen the traditional inventory and perception studies and emphasise on contributions that explore entrepreneurial developments of insects use as food and livestock feed. The issue also looked at emerging R&D and innovations to enhance the use of insects to improve food and nutritional security and as a major sector in economic development in Africa

Cuestiones reglamentarias, ambientales y de inocuidad, relacionadas con la cría y el comercio internacional de insectos comestibles en África

Insect breeding or farming for food and feed is an emerging enterprise that can address the ever-growing demand for protein and curb high unemployment rates in Africa and beyond. However, for the sector to prosper, its value chain needs to be regulated to ensure sustainability and safety for consumers and the environment. Although a few African countries, such as Kenya, Uganda and Rwanda, have promulgated standards on the use of insects as food and feed, greater efforts are needed in other countries, and relevant policies governing the sector need to be formulated. All over the globe, attention to the regulation of the edible insect sector is increasing, and more investment in the in- dustry is foreseen. Safety issues such as identifying which species should be reared, substrate quality and traceability imposed by importing countries will be critical for expansion of the sector. This paper analyses safety, regulatory and environmental issues related to breeding and international trade of edible insects in Africa and provides case studies and recommendations for sustainable use of insects for food and feed.La cría o producción de insectos con fines de alimentación humana o animal es una actividad incipiente que puede ayudar a responder a la siempre creciente demanda de proteínas y a contener las elevadas tasas de desempleo de África y otras regiones. Para que el sector prospere, no obstante, es preciso reglamentar su cadena de valor a fin de asegurar su sostenibilidad y su inocuidad para el consumidor y el medio ambiente. Aunque unos pocos países africanos, como Kenia, Uganda o Ruanda, tienen promulgadas normas sobre el uso de insectos para la alimentación humana o la producción de piensos, aún hay que redoblar esfuerzos en otros países y formular políticas que ordenen el sector. En todo el planeta se presta hoy una atención sin precedentes a la regulación del sector de los insectos comestibles, un sector que previsiblemente va a recibir cada vez más inversiones. Las cuestiones ligadas a la inocuidad, como la identidad de los insectos que se van a producir, la calidad del substrato o la rastreabilidad impuesta por los países importadores, serán fundamentales para el desarrollo del sector. Los autores analizan las cuestiones reglamentarias, ambientales y de inocuidad que se plantean en relación con la cría y el comercio internacional de insectos comesti- bles en África, presentan ejemplos concretos y formulan recomendaciones para un uso sostenible de los insectos con fines de alimentación humana o animal.Les élevages et les fermes d’insectes destinés à l’alimentation humaine et animale sont de nouvelles entreprises qui pourraient répondre à la hausse continue de la demande en protéines tout en réduisant les taux élevés du chômage en Afrique et ailleurs. Néanmoins, pour que ce secteur puisse prospérer, sa chaîne de création de valeur doit être réglementée afin de garantir sa durabilité et son innocuité pour les consommateurs et l’environnement. Si un petit nombre de pays africains dont le Kenya, l’Ouganda et le Rwanda ont élaboré des normes applicables à l’utilisation des insectes pour l’alimentation humaine et animale, dans d’autres pays les efforts doivent se poursuivre et des politiques appropriées doivent être mises en place pour régir ce secteur. Partout dans le monde, la réglementation du secteur des insectes comestibles fait désormais l’objet d’une attention considérable et des investissements accrus dans la filière sont attendus. Les questions de sécurité telles que l’identi- fication des insectes à élever, la qualité du substrat et la traçabilité exigée par les pays importateurs seront cruciales pour le développement du secteur. Les auteurs analysent les questions de sécurité et les enjeux réglementaires et environnementaux liés à l’élevage et au commerce international d’insectes comestibles en Afrique et présentent des études de cas et des recommandations pour une utilisation durable des insectes destinés à l’alimentation humaine et animale.Denmark’s development cooperation DANIDA through the project Healthynsect and the icipe core fund- ing provided by the Swedish International Development Cooperation Agency (SIDA); the Swiss Agency for Development and Cooperation (SDC); the Federal Ministry for Economic Cooperation and Development (BMZ), Germany; the Federal Democratic Republic of Ethiopia; the South African National Research Foundation; and the Government of the Republic of Kenya.https://www.woah.org/en/what-we-do/publications/scientific-and-technical-reviewhj2023Zoology and Entomolog