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White yam (Dioscorea rotundata L.) is widely cultivated, and is a staple food in the Republic of Benin. However, its production is highly sensitive to soil infertility, leading to low yields over the years. In order to address the challenges of land reduction and climate change, it is crucial to introduce more adapted yam varieties to traditional Beninese agriculture. Water yam (Dioscorea alata L.) varieties are viable options, as they need less soil fertility and yield more than D. rotundata, but have a poor culinary performance. The aim of this study is to assess the agronomic and culinary performance of 15 improved water yam genotypes developed by the International Institute of Tropical Agriculture (IITA) compared to local cultivars. In 2022 and 2023, multilocal trials (4 sites) were performed in the yam-growing areas, and nine villages were selected for culinary evaluation. Linear mixed-effects models and generalized mixed-effects models showed significant differences (p

X-ray applications in imaging and beyond require efficient and optimal detectors. Energy separation, time loss, and manufacturing cost are among the features that led us to design a semiconductor detector. A low-gain avalanche diode (LGAD) with internal amplification allows, in a sufficient field, the internal propagation process by accelerating the carriers, the energy required for ionization, and the generation of secondary carriers to produce a better gain (higher signal-to-noise ratio) and also provide more time efficiency (in the range of nanoseconds). In this article, we simulate the LGAD silicon detector with Silvaco software by applying reverse bias voltage and radiation in the range of visible light to X-ray. Newton and Gummel's methods were used. In Newton's method, one of the mechanisms of radiation interaction with matter is considered variable and the rest are fixed. However, in Gummel's method, all mechanisms are solved simultaneously. In the X-ray wavelength range, the electron current in this detector is 10-4 amperes, and this current decreases with increasing energy. The dark current is 10-6 amperes. By applying visible light with 0.45-micrometer wavelength and 1 V/cm2 intensity, the detector current was obtained about 6.5×10-4 amperes. For 1.0×10-5 x-ray wavelength and 108 V/cm2 intensity, detector current was obtained about 3.5×10-4 amperes. Considering the quick response time of this detector and the current in the range of microamps, this detector is a suitable option for X-ray detection. Also, this detector shows superior performance in the visible light range.

Objective: The present study aimed to see if 20-Deoxyingenol(20-DOI) could protect hippocampus neurons from the neurotoxic effects of morphine and reduce memory loss in rats. Method: Male Wistar rats were given morphine hydrochloride (45 mg/kg, sc, four weeks) and 20-DOI (10, 20 mg/kg, ip., coadministered with morphine) for the Morris Water Maze (MWM) test to investigate the effects of 20-DOI on spatial learning and memory. Western blotting was used to evaluate the expression of the hippocampal CA1 region of the cleaved caspase-3, Bax, and Bcl2 proteins and so on. Moreover, these assays were used to evaluate the expression of superoxide dismutase (SOD)2, heme oxygenase 1(HO1) protein, and glutathione peroxidase (GPx) activity within the hippocampus CA1 area. Results: The administration of 20-DOI (10 and 20 mg/kg) to morphine-treated mice enhanced spatial learning and reduced memory deficits. Additionally, 20-DOI treatment reduced apoptosis and oxidative stress in the hippocampal CA1 region of morphine-treated rats. Moreover, 20-DOI improved the autophagy level of the hippocampal CA1 area of morphine-treated rats using Transcription factor EB (TFEB), and 20-DOI prevented spatial learning and memory impairment in morphine-treated rats. The current observation could be partially due to the inhibition of neuronal apoptosis and oxidative stress in the hippocampal CA1 region of rats treated with morphine and the improved autophagy in this region. Conclusions: 20-DOI attenuated morphine administration in rats with chronic disease caused spatial learning and memory dysfunction. These mechanistic effects could be partially related to 20-DOI protecting the CA1 region of rat hippocampal neurons from the morphine-induced oxidative stress, apoptosis, and autophagy through TFEB.

Abstract Background Edible insects are important sources of essential nutrients and have the potential to contribute to malnutrition reduction and food security in the Republic of Benin. However, their consumption is always restricted to a limited number of sociocultural groups. To determine how the consumption of insects could be promoted as an alternative food source, this study documents the endogenous knowledge associated with edible insects and, the main factors that govern their perception and frequency consumption. Methods A survey was conducted towards 479 rural households consuming edible insects through 91 villages of Atacora, Alibori, Zou, and Plateau departments using individual interviews with a semi-structured questionnaire. The survey was focused on the inventory of edible insects and the documentation of consumers’ acceptance, frequencies and motive reason of consumption, local uses, and accessibility to edible insects. Samples of edible insects were collected and preserved in 70% alcohol for taxonomic identification. Results The majority of surveyed people (79.1%) were consumers of edible insects since many years ago (29.1 ± 17.2 years). Insect species belonging to 17 genera of 7 families and 3 orders of insects were used as food, with Brachytrupes membranaceus Drury being the most widespread and consumed. Six factors affecting edible insect availability were identified with the chemical pollution as the most important. Besides their food use (63.2%), edible insects in the study area were used for several purposes. We find that ethnicity, religion, age, education level, and monthly frequency of insect consumption are the main factors influencing the local perception of edible insects. Indeed ethnic group, religion ethnicity, and market accessibility have a positive influence on edible insect consumption frequency. The Hierarchical Clustering of Principal Components has allowed us to classify the interviewees into 3 groups with different perceptions of entomophagy and their characteristics will make it possible to better orient the strategies for promoting entomophagy in the Republic of Benin. Conclusions Religion and tradition are among the main factors that influence entomophagy in Benin Republic. The development of a national strategy to promote entomophagy should take into account the recorded insect consumption motivations, and their different uses by each ethnic group, and mainly target young people.

Abstract In recent years, Hooded Vulture populations in West Africa have decreased substantially. However, in some areas within this region, the species is still relatively abundant. To find out more about the situation in West Africa, we assessed the status of Hooded Vultures in Benin, one of the countries where their status is not well known. We conducted road counts on paved and unpaved roads and along small trails over a total of 1451 km. We also conducted interviews with local abattoir watchmen, veterinarians, butchers and foresters to examine potential threats to this species. A total of 52 Hooded Vultures were counted mostly in the departments of Atacora (32) but also in Alibori (10) and Borgou (10). The relative abundance was four Hooded Vultures per 100 km, highlighting the near extirpation of this bird from Benin. A total of 49 interviews revealed that poaching for belief‐based use (through shooting and traps) and decreasing food availability remain the most important threats for Hooded Vultures in northern Benin. If these threats are not mitigated, we predict the extirpation of the Hooded Vulture outside protected areas in Benin within the next two decades, possibly even sooner. Conservation measures, including awareness campaigns, and the improvement and enforcement of environmental legislation, must be urgently implemented to improve the protection of this Critically Endangered vulture species.

In Benin, the fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), is the most important polyphagous noctuid pest. This study aimed to assess the impact of agricultural practices on the abundance of this pest and determine whether its feeding preference and larval development differ among four cereal types. First, we conducted a descriptive survey of 80 farmers randomly selected for farm visits and oral interviews using a structured questionnaire to ascertain their preferred agricultural practices for managing S. frugiperda. Secondly, rearing methods in the laboratory were used to assess the development of the S. frugiperda maize strain feeding on maize, millet, rice, and sorghum. Data were collected on the number of larval instars, pupae, and adults as well as their developmental times. Agricultural practices were found to influence the abundance of S. frugiperda in the farmers' fields. The number of larvae was higher in sampling fields treated with herbicides alone. S. frugiperda larvae were reported to be more abundant on young vegetative plants, while the highest mortality rate was obtained on rice. In addition, the development level of S. frugiperda was fastest in maize, followed by sorghum, millet, and rice. The Structural Equation Models (SEM) showed significant relationships between the crop types and the abundance of development stages. Conversely, these relationships were significantly negative across the different stages of insect development. This study allowed us to understand the development level of the pest according to the different farmer's agricultural practices and its feeding preference to its potential cereal host plants.

Introduction: At present, the mu opioid receptor is the most important neuroaesthetics receptor in anesthesiology research, and the damage that it does to the nervous system is unknown.Methods: We investigated the effects of loperamide, an agonist of the mu opioid receptor, on protein expression in HT22 cells using stable isotope labeling of amino acids in cell culture (SILAC), immobilized metal affinity chromatography (IMAC) enrichment, and high-resolution liquid chromatography-tandem mass spectrometry (LC-MS/MS). A total of 7,823 proteins were identified.Results and Discussion: Bioinformatic analysis revealed that mu opioid receptor agonism can induce distinct changes in the proteome of HT22 cells. These findings improve our understanding of narcotic drugs.

Assessment of the functional and rheological characteristics of instant pounded yam (Dioscorea rotundata) flour obtained from the tubers of cultivars used as parents in a breeding program in Benin Description of the subject. In West Africa, yam tubers are mainly consumed in the pounded form. However, in view of the high perishability of fresh tubers, the consumption of pounded yam throughout the year is becoming a major concern. The transformation of tubers into stable products, such as instant flour that can give a dough with characteristics similar to that of pounded yam, has become a priority. Objectives. To evaluate the functional and rheological properties of instant pounded yam flour (InstAgoun) produced from 48 cultivars used as parents in a selection program on yams in Benin. Method. The flours from the 48 yam cultivars were characterized in terms of their color and their functional and rheological properties, using standardized methods. Results. The results showed that the flour yield (14.7 – 27.9%), color (L*: 70.1 – 83.9; a*: -1.2 – 1.6; b*: 0.8 – 13.6), solubility (6.4 – 11.9%), peak viscosity (1,048 – 4,376 cPs), final viscosity (1,568 – 6,251 cPs), holding strength viscosity (875 – 4,004 cPs), viscosity breakdown (14 – 592 cPs), viscosity setback (395 – 2,418 cPs), peak time (5 – 8 min) and the starch pasting temperature (73 – 93 °C) of the flours produced varied significantly depending on the yam cultivars. However, no significant difference was observed in the swelling power of the flours derived from the different cultivars, which varied from 3.2 to 5.1 g·g-1. In terms of functional and rheological characteristics, eight promising cultivars (Singor, Parayobou, Agbaobé, Portchahabim, Tarayè, Tchée, Anklouman, and Kpagninan) were identified as the most suitable for producing instant pounded yam flour. Conclusions. An effective introduction of these eight promising cultivars into breeding programs could generate varieties that will meet the quality requirements of the various program participants for the improvement of the yam value chain in the Republic of Benin.

Termites are considered as important pests of maize plantations in Republic of Benin. However, very little information is available on their assemblage composition, abundance, damages, and on the sensitivity of common maize varieties in Benin. This study aims to fill these gaps and provide baseline for the development of an integrated termite management in maize plantations. Therefore, 60 maize fields across 30 villages located in four agro-ecological zones of southern Benin were prospected using the standardized method of belt transects. In addition, the resistance of five maize varieties to termite attacks was evaluated on-farm during two consecutive seasons (2018 and 2019). Fifteen termite species belonging to 11 genera, 6 subfamilies and 3 families were collected in the prospected maize fields. Four species (Macrotermes subhyalinus Rambur, Coptotermes sjostedti Holmgren, Amitermes evuncifer Silvestri, and Trinevitermes germinatus Wasmann) were found in all agro-ecological zones with A. evuncifer as the most abundant species. High similarity indices of termite assemblages were found between the four agro-ecological zones. Wood-feeders group and species nesting in hypogeal nests were the mostly abundant in all agro-ecological zones. The attack rate of termites in maize fields was 16.9% and did not vary significantly between agro-ecological zones. A. evuncifer and C. sjostedti were significantly the most destructive species on the five evaluated varieties, although Trinevitermes oeconomus Trägardh was most abundant in leaf sheaths; M. subhyalinus and Macrotermes bellicossus Smeathman in the stem; Pseudacanthotermes militaris Hagen and Odontotermes sp. in the roots. Termite damage level to maize depended of the variety. Korga variety was classified as highly resistant to termite attacks; Agbadé kouin winiwini variety as resistant; Igbado tchakpa variety as moderately resistant. While, Elèkpèrè and Forkui varieties were classified as highly susceptible. The three maize varieties identified as resistant to termite attack should be included in the development of an integrated termite management program and in future breeding programs. [ABSTRACT FROM AUTHOR]

Monitoring genetic gain is crucial to ensure breeding programs' effectiveness and identify potential challenges and areas for their improvement. Our study provides a first overview of the trends in genetic gain for tuber yield and disease resistance traits in the IITA's (International Institute of Tropical Agriculture) yam breeding program. We used historical data (2010–2022) from multiple generations of past breeding cycles evaluated at 31 sites in the white Guinea yam (Dioscorea rotundata Poir) breeding pipeline and 28 sites in the water yam (Dioscorea alata L.) breeding pipeline of IITA and its national partners in West Africa. Our result shows positive genetic trends in fresh tuber yield while recording a gain of 1.38% or 99.17 kg ha−1 per year in the white Guinea yam and 2.18% or 252.41 kg ha−1 per year in the water yam breeding pipelines. Genetic trends for virus and anthracnose resistance were in the desired direction but negligible in white Guinea yam, while significant for virus and nonsignificant for anthracnose resistance in water yam. Our findings indicate that while the breeding program has succeeded in enhancing tuber yield, post‐harvest tuber dry matter content and disease resistance (yam mosaic virus and anthracnose) did not follow a similar trend in the material being developed. This implies that the yam breeding program needs to strike a balance between various traits, ensuring that increased yield does not come at a cost to food quality or disease resistance. Our results highlight the importance of continually monitoring and assessing the performance of a breeding program and making informed decisions about which traits to focus on for future improvement. Core Ideas: Periodic monitoring of genetic gain is crucial to making informed decisions about which traits to focus on.Yam breeding program needs to strike a balance between various traits for ensuring sustained genetic gain.High‐quality historical trial data crucial for assessing genetic gain trends in breeding programs. [ABSTRACT FROM AUTHOR]

Abstract Background Pigeonpea is a multipurpose food legume crop that contributes to food security in the Republic of Benin. For the establishment of conservation and breeding programs, previous ethnobotanical surveys on pigeonpea were done in Benin but restricted to south and central regions. In previous years, pigeonpea landraces were introduced in northern Benin for soil fertility management; it is therefore important to evaluate the diversity in this legume in this region. Exhaustive documentation of pigeonpea diversity grown in the Republic of Benin will be necessary for effective breeding and conservation programs. Therefore, the aim of this study was to document genetic diversity of pigeonpea, across the agro-ecological zones of the Republic of Benin for its promotion and valorization. Methods A total of 500 pigeonpea farmers representing 13 sociolinguistic groups were selected from 50 villages. The data were collected using methods and tools of participatory research appraisal. Folk nomenclatures, taxonomy of pigeonpea and seed system were investigated. The distribution and extent of pigeonpea landraces were evaluated using the Four Square Analysis method. A comparative analysis of pigeonpea use categories production systems, production constraints, famers’ preference criteria, and participative evaluation for existing landraces across agro-ecological zones was done. Result Folk nomenclature and taxonomy were mainly based on seed coat color and size. Seven pigeonpea use categories were recorded including sacrifice, grain processing and fertilization. The results showed that the pigeonpea seed system is informal. Based on seed characteristics, fifteen landraces were recorded including seven new landraces. The Sudano-Guinean zone contained the highest number (11) of landraces. The average number of landraces per village was 2.7. A high rate of landraces facing threat of disappearance was observed across the ecological zones. Ten constraints are known to affect pigeonpea production in Benin, with pests and diseases as the most critical in all agro-ecological zones. This study revealed that pigeonpea cultivation is increasing in the Sudanian zone. Varieties to be produced must be selected based on 11 criteria which included precocity and resistance to pests and diseases in the three ecological zones and adaptability to any type of soil in the Sudanian zone. The participatory evaluation revealed the existence of a few performing cultivars. Conclusions Our results revealed that implementation of a pigeonpea genetic conservation program in Benin must take into account the diversity, production constraints and varietal preference, which varied according to agro-ecological zones. In situ and ex situ conservation strategies are important to preserve pigeonpea landraces. Morphological and molecular characterizations of identified cultivars are highly recommended to help select suitable varieties for breeding programs.

Genetic diversity studies provide important details on target trait availability and its variability, for the success of breeding programs. In this study, GBS approach was used to reveal a new structuration of genetic diversity and population structure of pigeonpea in Benin. We used a total of 688 high-quality Single Nucleotide Polymorphism markers for a total of 44 pigeonpea genotypes. The distribution of SNP markers on the 11 chromosomes ranged from 14 on chromosome 5 to 133 on chromosome 2. The Polymorphism Information Content and gene diversity values were 0.30 and 0.34 respectively. The analysis of population structure revealed four clear subpopulations. The Weighted Neighbor Joining tree agreed with structure analyses by grouping the 44 genotypes into four clusters. The PCoA revealed that genotypes from subpopulations 1, 2 and 3 intermixed among themselves. The Analysis of Molecular Variance showed 7% of the total variation among genotypes while the rest of variation (93%) was within genotypes from subpopulations indicating a high gene exchange (Nm = 7.13) and low genetic differentiation (PhiPT = 0.07) between subpopulations. Subpopulation 2 presented the highest mean values of number of different alleles (Na = 1.57), number of loci with private alleles (Pa = 0.11) and the percentage of polymorphic loci (P = 57.12%). We discuss our findings and demonstrate how the genetic diversity and the population structure of this specie can be used through the Genome Wide Association Studies and Marker-Assisted Selection to enhance genetic gain in pigeonpea breeding programs in Benin.

To meet the high demand for white Guinea yam, there is a need to develop and release improved varieties to farmers. Unfortunately, low rate of adoption of most of the improved yam varieties by both producers and consumers was observed. Information regarding agronomic characteristics and food qualities of popular white Guinea yam landraces with high market value are not available to establish minimum standards to be considered by breeding programs. To fill this gap, surveys using rural appraisal tools were carried out in 20 villages and 16 markets throughout Benin. Data on the agronomic performance suggested that for an improved variety to be adopted by Beninese farmers it should have a minimum yield of 4.16 ± 0.15 kg per mound, and average number of marketable tubers of 1.23 ± 0.05, a mean tuber length of 36.41 ± 1.22 cm, and a minimum diameter of 25.44 ± 1.16 cm. The sensorial attributes for boiled and pounded tubers of this improved variety should have minimum score of 3.16 for texture, 0.75 for softness, 3.75 for elasticity, and 1.34 for colour during the sensory evaluation. The improved variety must also have a minimum average severity score of 1.1 for yam mosaic virus disease, 1.33 for anthracnose and 1 for nematodes. Landraces Amoula, Laboko, and Djilaadja should be considered as the standard for yield, sensory attributes, and tolerance to pest and diseases while landraces Danwari, Kodjewe, Mondji, and Gnidou should be characterized as possessing good flowering and fruit setting capacities for breeding programs.

The African eggplant (Solanum aethiopicum L.) is an important traditional vegetable cultivated in tropical regions for its edible fruits. In the Benin Republic, S. aethiopicum is mainly cultivated by rural farmers for food and for its use in traditional medicine. Assessing varietal diversity, endogenous knowledge, production constraints and farmers' preference criteria are of great importance for promotion and conservation purposes. Using rural appraisal tools and methods, an ethnobotanical study was conducted in 680 households across 92 villages. A total of 60 local cultivars were collected and documented in the surveyed sites. We documented 15 farmers’ criteria for agronomic (57.88% of responses), culinary (28.51%) preference, and for economic (13.61%) aspects. Several constraints related to eggplant production in Benin were also recorded. The low market demand (27% of responses), lack of high-yielding cultivars (11.08% of responses), low fruit storability (10.67%), low productivity (9.84%), soil poverty (8.43%), susceptibility to high soil moisture (8.02%), pests (9.56%), diseases (8.45%), and drought (6.38%) appeared to be the most important constraints of the eggplant production system in Benin. In addition to synthetic pesticides, the eggplant farmers use botanical plant extracts such as extracts from Azadirachta indica (Meliaceae) and Hyptis suaveolens (Lamiaceae). It appears that eggplant production is still traditional and is of limited use in Benin. Finally, the currently collected germplasm was proposed for further evaluation using morphological and molecular markers to provide breeders with traits of interest for developing better eggplant varieties and hybrids that are suitable for local environmental conditions and production systems.

Taro and new cocoyam are root and leaf crops commonly grown in tropical to warm temperate regions. In Togo, they are neglected and underutilised. Here we report the genetic diversity of 26 accessions of taro and 101 accessions of new cocoyam. Analysis of simple sequence repeats revealed low polymorphic information content of 0.43 and 0.25 in taro and new cocoyam, respectively. PCA scatterplots and Neighbour Joining dendrograms based on the SSR data clustered accessions into groups that more-or-less correspond to morphological diversity in both species. AMOVA within and between morphological groups revealed greater variances within groups than between. This indicates weak genetic differentiation between morphological groups, particularly for taro. Genetic diversity was greater among taro cultivars. Taro has a longer history of introduction and dispersal in Africa, and has had more opportunity for multiple introduction and local cultivar development. Different strategies are suggested for future development of these crops in Togo and Africa. For taro, further studies of existing diversity and recent experimental introduction, has spread widely in Africa with little genetic diversity. For this crop, international collaboration is needed to clarify taxonomy, and to introduced further cultivars for evaluation under local conditions in Africa.

Abstract Background Macrotyloma geocarpum Harms is a neglected and underutilized crop in Benin subject to several constraints including storage insect attacks, which contribute to the decrease in its production. An ethnobotanical survey using a semi-structured questionnaire was conducted in 15 villages in southern and central Benin to document farmers’ perceptions of M. geocarpum storage insect pests and their traditional management practices. Results The results showed that insect pest were the most important storage constraint of M. geocarpum. To overcome this constraint, the promotion of resistant landraces has been proposed by farmers. Six vernaculars names of storage insect pests of M. geocarpum were identified throughout the study area and all corresponding to Callosobruchus maculatus (F.) which proved to be the most abundant insect in the stocks. Palatability and fragility of seeds coat have been identified by farmers as the main factors favoring the infestation by this pest. Various storage containers of M. geocarpum have been inventoried. Our study revealed that education, storage containers, and Kersting’s groundnut landraces significantly influenced farmers’ perceptions of severity of insect pest damages. The use of chemicals and repellent plants were the main control methods used by farmers to protect stocks. Different levels of resistance of M. geocarpum landraces to storage insect pests were reported. Conclusions This study provides baseline information for development of integrated management approaches against storage insect pests of M. geocarpum. The perceived level of resistance to insect damage on Kersting’s groundnut landraces needs to be investigated.

Abstract Background The cultivated banana and plantain (Musa spp.) are valuable for nutritional and socio-economic security for millions of people worldwide. In Benin, banana and plantain are among the most produced, consumed, and traded commodities. Its production is mainly for local consumption and remains insufficient to the demand. However, the varietal diversity of banana and plantain cultivated in Benin is not documented. This study aims at characterizing the banana and plantain cropping systems, genetic diversity, and production constraints as a baseline to the full utilization of this resource in crop improvement and to identify the potential production and agronomic qualities. Methods A baseline investigation of ethnobotanical attributes of banana cultivars was done in 51 randomly chosen villages in southern Benin. Interviews with randomly selected representative farmers were carried out. Key informant interviews and focus group discussions were used for global confirmatory investigation of survey data. Socio-demographic data and indigenous knowledge on the farmer uses of banana and plantain diversity, such as cultural practices, origin, and availability of banana and plantain planting materials, and the constraints and criteria of varietal preference cited by farmers were ranked. Results Eighty-seven locally recognized cultivars were found: 73 of banana and 14 of plantain groups. The most popular cultivars were Sotoumon (banana) (52.94%), Aloga (plantain) (41.17%), Planta (banana) (33.33%), and Adjangan (plantain) (27.45%). Of the eleven production constraints identified, the main biotic challenges were banana weevil Cosmopolites sordidus Germar and banana bunchy top virus (BBTV), while abiotic problems were drought and the wind. Some local varieties like Amandan, Assonwonnou, Coleti, and Ninkouin are extremely rare owing to agronomic and economic preference perceptions. Conclusion and implications This study provides a baseline for banana diversity in Benin and the West African region and entry points for biological characterization and production improvement. This would enable the exploitation of this resource for plant breeding towards biotic and abiotic challenges facing banana production.

L’identification biochimique de Staphylococcus aureus nécessite la recherche de la staphylocoagulase libre, réalisée grâce au plasma lyophilisé de lapin. Cette étude vise à promouvoir l’utilisation de plasma frais d’animaux tropicaux et déterminer l’influence des anticoagulants, de la température et de la durée de conservation de ces plasmas dans la révélation de la staphylocoagulase libre.Cinq (5) échantillons de sang de rats wistar, 3 de porc, 10 de poulets et 10 de lapins ont été recueillis sur anticoagulants. Après caractérisation biochimique d’une souche de référence de S. aureus ATCC 25923, la recherche de la staphylocoagulase libre a été faite à partir des plasmas d’animaux tropicaux conformément aux critères bactériologiques classiques. Des résultats obtenus, seuls les échantillons de plasma de lapins et de porcs ont permis la révélation de la staphylocoagulase libre. De tous les anticoagulants testés, l’EDTA et Citrate de sodium ont été les plus efficaces. Une part des plasmas de lapins recueillis sur EDTA a été conservée au réfrigérateur et l’autre part à température ambiante durant sept jours. La recherche de la staphylocoagulase a été faite tous les jours de conservation à partir des plasmas. Il découle de cette conservation que la température n’a pas d’influence majeure sur les échantillons de plasma sauf que leur conservation à température ambiante ralentit l’obtention des résultats. Il est donc préférable pour l’obtention de résultats dans un temps relativement court et pour éviter les risques de contamination des plasmas, de les conserver au réfrigérateur entre 2° et 8°C pendant un maximum de 6 jours.

Le manque de terres cultivables dans le centre du Bénin a conduit les producteurs à associer les cultures vivrières et l’anacardier. Cette pratique agro-forestière permet aux producteurs de diversifier leurs sources de revenus et d’alimentation, ce qui constitue un gage de la sauvegarde des ressources naturelles et du respect de l’environnement. La présente étude a été réalisée dans le centre du Bénin dans les communes de Dassa-Zoumé, Glazoué et Bantè dont les données de 88 producteurs ont fait objet de traitement et d’analyse. L’objectif de cette recherche est de déterminer la performance agro-environnementale de chacun des systèmes agro-forestiers à base d’anacardier pratiqués dans le centre du Bénin. Ainsi, après un inventaire, 14 systèmes agro-forestiers à base d’anacardier ont été identifiés. Parmi ces derniers, huit (08) agro-systèmes ont intéressé cette étude. Les plus performants sur le plan agro-environnemental, en se basant sur la perception paysanne de leurs rendements, étaient en premier le système anacardier-igname suivi par le système anacardier-manioc et le système anacardier-coton permettant de garantir au mieux la sécurité financière, la qualité nutritionnelle et le respect de l’environnement. De plus, la culture d’igname est plus mentionnée par les producteurs comme culture favorable au développement de plants d’anacardier. Mots clés: Systèmes agro-forestiers, anacardier, culture annuelle, performance agro-environnementale, centre Bénin

Cultivated yam (D. rotundata) is a staple tuber crop in West Africa whose sexual reproduction control remains largely unknown despite its importance for plant breeding programs. In this paper, we compared self-pollination, intracultivar cross-pollination and intercultivar cross-pollination in three monoecious cultivars (Amoula, Heapala and Yassi). Results showed that pollen viability (49%) and stigma receptivity (40%) were similar in monoecious and dioecious plants, suggesting that autogamy could occur in monoecious plants. However, fruit and seed sets were significantly lower after self-pollination compared to cross-pollination. Overall, autogamy reached 11% and pollen lability was almost zero (D. rotundata even after cross-pollination as fruit and seed set did not exceed 18% and 13% respectively. Moreover, comparison between intracultivar cross-pollination and self-pollination revealed intravarietal genetic diversity inside the analyzed yam cultivars. Overall, our results showed that D. rotundata has a very low tolerance to autogamy in monoecious cultivars and has developed pre- and postzygotic mechanisms to limit selfing.

Abstract Background Common bean (Phaseolus vulgaris L.) is an important grain legume crop grown in the central region of the Republic of Benin. However, its production declined in recent years to the extent that its diversity is being threatened with extinction. Understanding the folk nomenclature and taxonomy, as well as use values that allow its maintenance in Beninese agricultural system, is a prerequisite to develop efficient strategies for its conservation. Knowing that each sociolinguistic group develop various uses and traditional knowledge for their crop genetic resources, we hypothesized that enhancement of farmers’ livelihood, thanks to the use values of common bean landraces, differ from one sociolinguistic group to another and contribute to their conservation in the traditional agriculture of central Benin. Methods Hundred and one common bean producers belonging to seven sociolinguistic groups selected through 23 villages of the region under study were surveyed. Data were collected through participatory research appraisal tools and techniques (individual interviews and direct observation) using a semi-structured questionnaire. Folk nomenclature and taxonomy of common bean, local uses, and factors affecting them were investigated. Results Across the seven sociolinguistic groups surveyed in the study area, five common bean generic names and 26 folk varieties corresponding to 12 landraces have been recorded. Folk nomenclature and taxonomy were mainly based on seeds’ coat color. The present study has revealed five common bean use values in the study area (food, medicinal, commercial, fodder, and mystic-religious), which are influenced by sociolinguistic groups. Leaves, roots, and seeds of three common bean folk varieties are used by surveyed farmers for disease treatment. Nine common bean folk varieties are considered by farmers as magical plants which have supernatural properties while several taboos for deities’ followers regarding Séssé landrace are inventoried across sociolinguistic groups. Level of education and age of respondents influence positively and significantly medicine and mystical-religious uses of common bean respectively while commercial use is positively influenced by age and negatively by gender. Conclusions Traditional values associated with common bean landraces in the central region of the Republic of Benin increase their chance of survival in the farming systems. Socio-demographic characteristics of respondents which influence common bean use values must be taken into account in future programs of conservation. However, an assessment of diversity and analysis of distribution of extend of common bean landraces in the study area is a necessity for the development of an efficient strategy of conservation of this genetic resource.

Abstract Background It has been known that Dexmedetomidine pre-medication enhances the effects of volatile anesthetics, reduces the need of sevoflurane, and facilitates smooth extubation in anesthetized children. This present study was designed to determine the effects of different doses of intravenous dexmedetomidine pre-medication on minimum alveolar concentration of sevoflurane for smooth tracheal extubation (MACEX) in anesthetized children. Methods A total of seventy-five pediatric patients, aged 3–7 years, ASA physical status I and II, and undergoing tonsillectomy were randomized to receive intravenous saline (Group D0), dexmedetomidine 1 μg∙kg−1 (Group D1), or dexmedetomidine 2 μg∙kg−1 (Group D2) approximately 10 min before anesthesia start. Sevoflurane was used for anesthesia induction and anesthesia maintenance. At the end of surgery, the initial concentration of sevoflurane for smooth tracheal extubation was determined according to the modified Dixon’s “up-and-down” method. The starting sevoflurane for the first patient was 1.5% in Group D0, 1.0% in Group D1, and 0.8% in Group D2, with subsequent 0.1% up or down in next patient based on whether smooth extubation had been achieved or not in current patient. The endotreacheal tube was removed after the predetermined concentration had been maintained constant for ten minutes. All responses (“smooth” or “not smooth”) to tracheal extubation and respiratory complications were assessed. Results MACEX values of sevoflurane in Group D2 (0.51 ± 0.13%) was significantly lower than in Group D1 (0.83 ± 0.10%; P

Yam is a strategic crop in Togo. Inventory and evaluation of cultivated varieties in different traditional agroeco-systems allows safeguard of this genetic heritage and its use in breeding programs. As welle ethnobotanical surveys were conducted in 30 localities of Kara region. The inventory allowed the recording 134 yam varieties distributed as follow 122 of D. cayenensis D. rotundata complex (56.46% early varieties and 43.54% late varieties) and 12 varieties of the type D. alata. The varietal richness by site varies betewen 7 and 30 with a predominance of D. cayenensis-D. rotundata. Varietal diversity has increased in 22% of villages because of varietal introductions representing 19.2% of the varieties. They come mainly from Bénin (52%), Ghana (40%) and Nigeria (8%). The exchange (45%), inheritance (65%), the gift (72.5%) and the purchase (35%) are the varieties acquisition modes. In contrast to 78% of the localities there is a reduction of varietal diversity. Ten main factors mainly agronomic and social are the cause of the reduction. 83% of the varieties are sparsely distributed and require urgent action on farm conservation because they are endangering. The storage may be done in 9 over the 30 localities that has about 80% of the varietal diversity.