Prostephanus truncatus is one of the most damaging post-harvest pests of stored maize in Africa. Research Institutions disseminated Various control strategies during the 1990s in West Africa with significant results. What is farmers’ perception of this pest in decades after those control strategies? This study aimed to assess determinants of farmers’ perception of current damages and losses caused by Prostephanus truncatus on stored maize in southern of the two countries (Benin and Togo). 300 maize farmers (150 from Togo and 150 from Benin) were randomly selected from 10 villages per country. Descriptive statistics were used in addition to Logit and Tobit regression analysis. The results showed that 38% of farmers (35% in Togo and 41% in Benin) still perceive Prostephanus truncatus as the most damaging pest of stored maize. Logit's results showed that factors influencing farmers’ perception of Prostephanus truncatus were group membership, contact with extension agents, and period of maize harvesting. The results from the Tobit regression model showed that factors such as the maize variety, the form of maize storage (with husk), and the storage period influence the extent of damage and loss caused by Prostephanus truncatus. Farmers still perceive Prostephanus truncatus as the main post-harvest pest causing high damage and losses on maize. It is recommended that further dissemination of maize storage technology to reduce postharvest losses.

The objective of this study was to evaluate the presence of Aspergillus section Flavi and A. section Nigri in cashew nuts harvested in the Northern Guinea (NG) and Southern Sudanian (SS) agro-ecological zones of Benin. Also, the presence of aflatoxins was investigated. For detection of fungal contamination, a total of 100 kernels/sample (with disinfection) and 40 kernels/sample (without disinfection) were plated. Seventy samples from fourteen villages were used. Aflatoxins occurrence was analysed on 84 samples by ultra high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). The average water content and the cashew nuts count were respectively 8.6% and 172 nuts/kg in NG and 8.7% and 174 nuts/kg in SS. Significant differences between villages in both zones were found for both water content and nuts count. In disinfected samples, strains of Aspergillus section Nigri were predominant, in NG and SS zones (90.2% and 87.2%) respectively. When non disinfected kernels were plated, A. section Nigri was predominant in both NG and SS zones, with percentages of 89.7% and 93.4%, respectively. None of the 84 nuts samples were positive for natural occurrence of aflatoxins with a detection limit of 0.05-0.2 mu g/kg. (C) 2016 Elsevier Ltd. All rights reserved.

In a previous study, raw cashew kernels were assayed for the fungal contamination focusing on strains belonging to the genus Aspergillus and on aflatoxins producers. These samples showed high contamination with Aspergillus section Nigri species and absence of aflatoxins. To investigate the diversity of secondary metabolites, including mycotoxins, the species of A. section Nigri may produce and thus threaten to contaminate the raw cashew kernels, 150 strains were isolated from cashew samples and assayed for their production of secondary metabolites using liquid chromatography high resolution mass spectrometry (LC-HRMS). Seven species of black Aspergilli were isolated based on morphological and chemical identification: A. tubingensis (44%), A. niger (32%), A. brasiliensis (10%), A. carbonarius (8.7%), A. luchuensis (2.7%), A. aculeatus (2%) and A. aculeatinus (0.7%). From these, 45 metabolites and their isomers were identified. Aurasperone and pyranonigrin A, produced by all species excluding A. aculeatus and A. aculeatinus, were most prevalent and were encountered in 146 (97.3%) and 145 (95.7%) isolates, respectively. Three mycotoxins groups were detected: fumonisins (B2 and B4) (2.7%) ochratoxin A (13.3%), and secalonic acids (2%), indicating that these mycotoxins could occur in raw cashew nuts. Thirty strains of black Aspergilli were randomly sampled for verification of species identity based on sequences of β-tubulin and calmodulin genes. Among them, 27 isolates were positive to the primers used and 11 were identified as A. niger, 7 as A. tubingensis, 6 as A. carbonarius, 2 as A. luchuensis and 1 as A. welwitschiae confirming the species names as based on morphology and chemical features. These strains clustered in 5 clades in A. section Nigri. Chemical profile clustering also showed also 5 groups confirming the species specific metabolites production.

Pachyrhizus erosus is a legume plant that produces tubers rich in nutrients (protein, iron, zinc, etc.) that are used in various kinds of food processing. The objective of this study was to analyse producers’ and processors’ perception regarding processing P. erosus tubers into gari in on-farm conditions and its financial profitability. Kendall’s concordance test was used to classify perceptions, and cost analysis was used to analyse the profitability of the product. The results showed that the mixed gari with 50% P. erosus was highly appreciated because of its greater fermentation ability than cassava gari. The price at which processors broke even was FCFA 340 (~ $ 0.57) per kilogram and the sensitivity analysis revealed that when the yield of P. erosus -based gari increased by 30%, processors made a profit of 25% of the investment cost. So, processing of P. erosus is beneficial for the processors and consumers appreciate it more than cassava gari. The Benin Government needs to promote this crop in order to feed its population. © 2015 International Formulae Group. All rights reserved. Keywords: Roots and tubers, technical performance, malnutrition, Benin, population, food quality

The introduction of P. erosus cultivation in Benin is for producers an alternative to improve their cropping system and for the population to improve their food system. Therefore, to remove the different constraints related to P. erosus adoption, this study has analyzed the perceptions of producers and the economic performances of P. erosus introduced in Southern and Center Benin. The data were collected from fifty eight (58) producers in 2011-2012, seventy three (73) in 2012-2013 and fifty nine (59) who have experienced P. erosus production. Analyses were made using the margin calculation methodology, the productivity calculation methodology, Kendall’s T tests and cost function modeling. The results revealed that P. erosus production is very profitable with a net margin of Fcfa /ha 2,064,284.63 /ha against Fcfa/ha 192,152.01 /ha, Fcfa/ha 551,900.93 /ha and Fcfa/ha 109,351.28 /ha respectively for cassava, sweet potato and maize.

Cassava chips were stored for 8 months in PICS bags, with half of the bags having a natural initial insect infestation, and the other half having this initial natural infestation augmented with 50 Prostephanus truncatus adults. Chips stored in traditional woven polypropylene bags served as controls. Oxygen levels varied during storage from 19.98 to 17.56%, 20.4 to 18.40%, and 20.24 to 19.92%, respectively, in PICS bags with augmented infestation (PICS-A), PICS bags under natural infestation levels (PICS-N) and polypropylene bags (WPP). Carbon dioxide levels varied from 0.73 to 3.90%, 0.65-3.56%, and 0.20-0.61%, respectively, in the three types of bags. P. truncatus populations were significantly higher in PICS-A reaching 98.66 +/- 7.21 individuals/kg at the end of storage, compared to 92.66 +/- 4.71 in PICS-N and 100.55 +/- 3.56 in WPP. Dinoderus spp. density was significantly higher in WPP with 270.55 +/- 20.59 individuals/kg after 8 months. The number of holes on chips and weight losses also increased with storage duration in all three treatments, but were significantly higher in WPP. Holes created by insects were noticed in PICS bags and were more important in the inner HDPE (high-density polyethylene) layer than in the outer HDPE layer. Up to 1913.00 +/- 114.13 holes were observed on the inner HDPE layer of PICS bags and 1039.00 +/- 29.40 in the outer HDPE layer. Hermetic storage bags prolong the storability of chips by approximately 1 month. PICS efficacy was probably affected by the large size of traditional cassava chips with large airspaces between individual chips, leading to a large oxygen store for insects which could not be used up through biotic activity, so that bags were not hermetic. In conclusion, PICS bags cannot be recommended for the storage of large sized traditional cassava chips. (C) 2014 Elsevier Ltd. All rights reserved.

A total of 420 samples were collected from agrarian households. Whereas 51% (215/420) of the samples were contaminated with one or more toxins, the contamination rates for maize, peanut, and cassava products were 74, 62, and 24%, respectively. The fumonisins (20-5412 μg/kg), aflatoxin B1 (6-645 μg/kg), roquefortine C (1-181 μg/kg), and deoxynivalenol (27-3842 μg/kg) were the most prevalent contaminants in maize. For peanut samples, aflatoxin B1 (6-125 μg/kg) and ochratoxin A (0.3-12 μg/kg) were the main contaminants, whereas aflatoxin B1 (6-194 μg/kg) and penicillic acid (25-184 μg/kg) were detected in the cassava products. Exposures calculated through maize intake for fumonisin B1 and aflatoxin B1 were several-fold higher (2-5 for fumonisin B1 and 10(4)-10(5) for aflatoxin B1) than the health-based guidance values of 2 μg/kg bw/day and 0.15 ng/kg bw/day, respectively. The study design constitutes a good model that can be implemented in other sub-Saharan African countries.

This paper examines cassava and "gari'' markets in southern and central Benin. The study highlights the performance of the aforesaid markets as well as the constraints related to their development. The investigations were conducted with 52 traders in southern and central Benin. From the field observations and data analysis, it came out on one hand that cassava and "gari'' markets in southern and central Benin are run mainly by women with a low level of formal education. On the other hand, these markets are concentrated and contestable. The first three major constraints limiting the development of the observed markets are the difficulties of supply, the lack of financial resources or means, and sales issues. As policy implication, traders and especially retailers should be gathered in commercialization groups or cooperatives. Policy interventions should also be aimed at improving supply conditions by facilitating the traders' access to production or processing points.

Aflatoxins are produced by Aspergillus flavus and A. parasiticus in oil-rich seed and grain crops and are a serious problem in agriculture, with aflatoxin B₁ being the most carcinogenic natural compound known. Sexual reproduction in these species occurs between individuals belonging to different vegetative compatibility groups (VCGs). We examined natural genetic variation in 758 isolates of A. flavus, A. parasiticus and A. minisclerotigenes sampled from single peanut fields in the United States (Georgia), Africa (Benin), Argentina (Córdoba), Australia (Queensland) and India (Karnataka). Analysis of DNA sequence variation across multiple intergenic regions in the aflatoxin gene clusters of A. flavus, A. parasiticus and A. minisclerotigenes revealed significant linkage disequilibrium (LD) organized into distinct blocks that are conserved across different localities, suggesting that genetic recombination is nonrandom and a global occurrence. To assess the contributions of asexual and sexual reproduction to fixation and maintenance of toxin chemotype diversity in populations from each locality/species, we tested the null hypothesis of an equal number of MAT1-1 and MAT1-2 mating-type individuals, which is indicative of a sexually recombining population. All samples were clone-corrected using multi-locus sequence typing which associates closely with VCG. For both A. flavus and A. parasiticus, when the proportions of MAT1-1 and MAT1-2 were significantly different, there was more extensive LD in the aflatoxin cluster and populations were fixed for specific toxin chemotype classes, either the non-aflatoxigenic class in A. flavus or the B₁-dominant and G₁-dominant classes in A. parasiticus. A mating type ratio close to 1∶1 in A. flavus, A. parasiticus and A. minisclerotigenes was associated with higher recombination rates in the aflatoxin cluster and less pronounced chemotype differences in populations. This work shows that the reproductive nature of the population (more sexual versus more asexual) is predictive of aflatoxin chemotype diversity in these agriculturally important fungi.

Mycotoxins contamination in some agricultural food commodities seriously impact human and animal health and reduce the commercial value of crops. Mycotoxins are toxic secondary metabolites produced by fungi that contaminate agricultural commodities pre- or postharvest. Africa is one of the continents where environmental, agricultural and storage conditions of food commodities are conducive of Aspergillus fungi infection and aflatoxin biosynthesis. This paper reviews the commodity-wise aetiology and contamination process of aflatoxins and evaluates the potential risk of exposure from common African foods. Possible ways of reducing risk for fungal infection and aflatoxin development that are relevant to the African context. The presented database would be useful as benchmark information for development and prioritization of future research. There is need for more investigations on food quality and safety by making available advanced advanced equipments and analytical methods as well as surveillance and awareness creation in the region.

After insects, mites are the major arthropod pests that inhabit stored agricultural products worldwide. To determine the acarofauna that infests cowpea, maize, paddy rice and sorghum in Benin (West Africa), surveys were conducted in some principal markets (Dantokpa, Glazoue and Parakou) of this country. A total of 555 samples of grains and debris were collected in May and September 2011. More than 56 species belonging to 24 mite families were recorded in the four products. These mite species included predators, parasites, fungivorous, phytophagous and other groups whose feeding habits are not well known. The family Cheyletidae was the most prevalent and the most diverse predatory mite family encountered, in which Cheyletus malaccensis Oudemans was the most abundant species. Several families of mite pests and mites responsible for allergies (Acaridae, Glycyphagidae, Pyroglyphidae, Pyemotidae and Saproglyphidae) were also detected. The three most dominant and frequent species were C. malaccensis, Suidasia nesbitti (Hughes) and Suidasia sp. Statistical analysis showed that densities of these three mite species were higher in Parakou than in Glazoue and Dantokpa, on one hand, and higher in debris than in grains, on the other hand. The densities of S. nesbitti and Suidasia sp. decreased significantly during the dry season, whereas C. malaccensis remained stable throughout the two samplings. Of all grains, sorghum was the least infested with mites. This study shows that in Benin mites are present in stored agricultural products to which they cause serious damage, and may cause various allergies to people.

Yam bean (Pachyrhyzus erosus) tubers were processed singly and mixed with cassava into different types of gari (100% yam bean gari, 75% yam bean gari, 50% yam bean gari and 25% yam bean gari) following the traditional gari processing method. Conventional gari from cassava was processed following the same approach and used as control. Physical characteristics, proximate composition and sensory quality of the garis obtained were assessed. Results showed that low and medium (25% and 50%) yam bean fortified gari processing yielded better than 75% and 100% yam bean gari processing. Low and medium yam bean gari were the closest to conventional gari regarding the brown index (18.0 and 18.3 respectively), had good swelling capacity (≥ 3) and had higher relative bulk density (0.57 and 0.53 respectively). The proteins content of the processed yam bean garis increased with increasing incorporation rate of yam bean but, similarly, the crude fibres content increased going beyond the recommended level of 2% maximum. The processed garis were used to cook èba which were submitted to panellists’ appreciation. Panellists scored better low and medium yam bean fortified garis and the resulting èba. Combining the results, the highest suggested incorporation rate was 50% yam bean tubers. © 2013 International Formulae Group. All rights reserved.Keywords: Legume tuber-root crop, quality, physical characteristics, chemical composition, sensory evaluation.

The purpose of this research is to screen different processes that could potentially decrease or even eliminate rotenone, a toxic isoflavonoid, from Pachyrhizus seeds. Yam bean seeds have very interesting nutritional characteristics, especially their high protein and lipid contents, and could potentially increase food security in under-nourished populations. However, they contain rotenone, a natural molecule previously used as an insecticide inhibiting the respiratory mitochondrial chain. It was also proven to be toxic to mammals as chronic exposure leads to the development of Parkinson-like symptoms in rats. As the thermosensitivity of rotenone had been reported, this study tested different processes (drying, roasting, boiling, frying, alcohol extraction), tegument removal, and traditional Beninese culinary recipes. Rotenone was then quantified in end-products by a validated method, associating microwave extraction, solid phase extraction (SPE), and HPLC-UV. With these processes a rotenone removal of up to 80% was obtained. The most effective methods were the drying and roasting of the seeds and the maceration of their flour in local alcohol. Rotenone degradation and elimination were confirmed by cytotoxic assays, effectively inducing a decrease in sample toxicity.

Fungal contaminants in major food staples in Kenya have negatively impacted food security. The study sought to investigate peanut market characteristics and their association with levels of aflatoxin in peanuts from Western, Nyanza and Nairobi Provinces of Kenya. Data were collected from 1263 vendors in various market outlets using a structured questionnaire, and peanuts and peanut products from each vendor were sampled and analyzed for aflatoxin levels. Thirty seven per cent of the samples exceeded the 10 μg/kg regulatory limit for aflatoxin levels set by the Kenya Bureau of Standards (KEBS). Raw podded peanuts had the lowest (χ2 = 167.78; P < 0.001) levels of aflatoxin, with 96% having levels of less than 4 μg/kg and only 4% having more than 10 μg/kg. The most aflatoxin-contaminated products were peanut butter and spoilt peanuts, with 69% and 75% respectively, exceeding 10 μg/kg. A large proportion of peanuts in the country (44%) were traded through informal open air markets; 71.8% of products from supermarkets were safe according to KEBS and the EU regulatory limits, while only 52% from informal markets met this threshold (χ2 = 95.13; P < 0.001). Packaging material significantly (χ2 = 73.89; P < 0.001) influenced the amount of aflatoxin in the product, with the majority (68%) of peanut samples that were stored in plastic jars having >10 μg/kg of aflatoxin. Over 70% of all storage structures were poorly ventilated and dusty. Sorting comprised 53% of the various crop protection measures used by traders post-harvest. To reduce aflatoxin exposure to consumers, set standards need to be complemented by strict monitoring systems and education of producers, processors and consumers in crop commodities other than maize, which has received the most attention in Kenya. Alternative uses of contaminated produce need to be explored.

The effects of soil inoculation with A. flavus, variety and cropping system on the level of aflatoxin in stored maize were investigated under crop storage conditions in Benin. The experiment was organized in a factorial scheme (two varieties x two cropping system x with or without A. flavus soil inoculation) with eight treatments carried out in a completely randomized block design with three replications. A. flavus incidence in the plots soil was assessed both before and after soil inoculation. The harvested maize was stored for four months and cobs were sampled in a monthly interval and analyzed for the determination of Fusarium spp. colonization, Penicillium spp. and A. flavus cfu levels, insect pests population size and aflatoxin content. Multi-factorial analysis of variance and linear regression analyses with dummy variables were used to compare treatments. The concentrations of aflatoxin B 1 and B 2 in the kernels tended to increase with time during storage. Variety and fungal inoculation were the main factors influencing the levels of aflatoxins in stored maize. The improved variety showed a higher number of A. flavus cfu and aflatoxin B 1 and B 2 levels as compared to the local variety. Intercropping with Vigna unguiculata decreased the aflatoxin concentration in the improved variety but not in the local variety. The local variety had higher levels of Penicillium spp. and lower levels of Fusarium spp. than the improved variety. The treatments had no effect on the populations of the most common storage insect pests, but their levels were positively correlated with aflatoxin content. Both the initial inoculum level and the variety effect on the water content of the kernels after harvest played a significant role in A. flavus infection.

Maize was artificially infested with either 10 or 25 individual Prostephanus truncatus (Horn) and Sitophilus zeamais (Motschulsky) or a mixture of both, and stored in a hermetic grain bag (HGB) or a woven polypropylene bag (WPB) for 150 days. Population growth of P. truncatus and S. zeamais during storage was low in HGB, while in WPB, the insect population increased significantly with storage duration. Mortality rate during storage was significantly higher in HGB than in WPB. After 60 days of storage, the average mortality rate of 99.50% was observed in HGB infested with 25 P. truncatus, and 100% for S. zeamais at the same infestation density after 90 days of storage. Grain losses were significantly lower in HGB compared with WPB. Less than 0.5 and 6.0% losses were obtained, respectively, for S. zeamais and P. truncatus in HGB infested with 25 individual insects after 150 days of storage, whereas losses of 19.2% (infestation with S. zeamais) and 27.1% (infestation with P. truncatus) were observed in WPB. HGB seems to be resistant to the perforation of S. zeamais, but not to P. truncatus. The moisture content of maize grains stored in HGB remained practically the same during storage, compared with the levels in WPB, which reduced with storage time. WPB could be used for maize storage, protecting it against insect infestation without the need for insecticide use.

In 2003/2004 and 2004/2005 in two agroecological zones fungi, mycotoxins and insects in cassava and yam chips were evaluated. Interaction of season, zone and time with fungal occurrence and incidence (cfu/g) and aflatoxin and fumonsin level. Mean moisture content was 11.9% and 12.4% with levels in the Northern Guinea Savannah (NGS) exceeded the recommended limit of 9-10% (2003-04). In the Sudan Savannah (SS), moisture content ranged from 10.1 to 14.5% and 11.1 to 14.5% in cassava and yam chips, respectively. During the 2004/2005 moisture ranged from 9.5 to 13.6% in the NGS and from 9.2 to 13.8% in the SS. The insects’ species identified included Prostephanus truncates, Cathartus quadricollis, Carpophilus dimidiatus, Tribolium casteneum and Sitophilus zeamais. P. truncates and C. quadricollis were more prevalent in cassava than yam. After three months, all stored cassava chips were infested by P. truncates and C. quadricollis, whereas no yam chips in the SS showed insects. A. flavus was the most predominant fungal species its prevalence varied with season, during storage period and agroecological zone. Fungal levels in cassava and yam chips reached 8950 cfu/g and 6030 cfu/g, respectively, exceeding the tolerance limit in foodstuffs (10). Other fungal species included Penicillium chrysogenum, Mucor piriformis, Phoma sorghina, Fusarium verticillioides, Rhizopus oryzae and Nigrospora oryzae. High performance liquid chromatography (HPLC) analysis of both cassava and yam chips showed that they were not contaminated by either aflatoxins or fumonisin B1. The limits of detection were 0.1μg/kg for all the aflatoxins and 0.025μg/kg for fumonisin B1.

Aflatoxins are secondary fungal metabolites that contaminate agricultural commodities and can cause sickness or death in humans and animals. Risk of aflatoxin contamination of food and feed in Africa is increased due to environmental, agronomic and socio-economic factors. Environmental conditions especially high humidity and temperature favour fungal proliferation, but also drought conditions increase risk of aflatoxin contamination. Low-input farming practices compound fungal and aflatoxin contamination of crops. The socio-economic and food security status of the majority of inhabitants of sub-Saharan Africa leaves them few options for choosing low-risk and high quality products. Several technologies have been tested in Africa to reduce aflatoxin risk. Field management practices that increase yields can reduce the risk of aflatoxin development. They include use of resistant varieties, crop rotation, well-timed planting, weed control, pest control especially control of insect pests and avoiding drought and nutritional stress through fertilization and irrigation. Measures to stop the infection process by controlling the aflatoxin causing fungi in the field are achieved through use of pesticides and atoxigenic fungi to competitively displace toxigenic fungi, and timely harvest. Post-harvest interventions that reduce aflatoxin include rapid and proper drying, proper transportation and packaging, sorting, cleaning, drying, smoking, post harvest insect control, and the use of botanicals or synthetic pesticides as storage protectants. Another approach is to reduce the frequent consumption of 'high risk' foods (especially maize and groundnut) by consuming a more varied diet, and diversifying the diet into less risky staples like sorghum and millet. Chemo-preventive measures that can reduce aflatoxin effect include daily consumption of chlorophyllin or oltipraz and incorporating hydrated sodium calcium alumino-silicates into the diet. Reduction and detoxification of aflatoxin is often achieved physically (sorting, physical segregation, flotation etc.), chemically (e. g. calcium hydroxide, ammonia) and microbiologically by incorporating pro-biotics or lactic acid bacteria into the diet. Millers can use blending of less and more contaminated products to reduce the overall risk. There is need for efficient monitoring and surveillance with cost-effective sampling and analytical methods to reduce risk in Africa. Public education and awareness can sensitize the population on aflatoxin risk and its management.

Maize production in Benin, especially in resource-poor farmers' fields, is constrained by stemborers among other factors. One of the major stemborers in southern Benin is Sesamia calamistis Hampson (Lepidoptera: Noctuidae). African farmers cannot afford to use commercial insecticides for controlling stemborers - they are expensive and unsuitable for durable pest management systems due to eco-toxicity. There is therefore a need for cheaper and environmentally friendly methods and botanicals offer an attractive alternative. The bushmint, Hyptis suaveolens (L.) Poit. (Lamiales: Lamiaceae), was compared with the commercial insecticide Furadan (carbofuran) for the control of S. calamistis on maize Zea mays L. (Poales: Poaceae). Trials were conducted in the screenhouse and in the field during the minor cropping season in 2004 at the International Institute of Tropical Agriculture (IITA)-Benin station. The variables measured included numbers of egg masses per plant, eggs per egg mass (in the screenhouse study), population density of S. calamistis, percentage of infested plants and/or ears, and deadhearts in the field. Irrespective of the variable considered, the aqueous extract of H. suaveolens compared favorably with Furadan while maize surrounded by live H. suaveolens plants had lower S. calamistis densities.