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Abstract Background Although termites are considered as agricultural pests, they play an important role in maintaining the ecosystem. Therefore, it matters to investigate the farmers’ perception of the impacts of the termites on the agriculture and their indigenous utilization. Methods A semi-structured questionnaire was used to interview 94 farmers through 10 villages of Atacora department, in the northwestern region of Benin, to obtain information for the development of successful strategies of termite management and conservation. Their perceptions on the importance and management of termites along with the indigenous nomenclature and utilization of termite mounds were assessed. Termite species identified by farmers were collected and preserved in 80% alcohol for identification. Results Eight crops were identified by farmers as susceptible to termites with maize, sorghum, and yam as being the most susceptible. According to farmers, the susceptibility to termites of these crops is due to their high-water content and sweet taste. A total of 27 vernacular names of termites were recorded corresponding to 10 species, Amitermes evuncifer, Macrotermes subhyalinus, and Trinervitermes oeconomus being the most damaging termite species. All the names given to termite species had a meaning. The drought was identified by farmers as the main factor favouring termite attacks. Demolition of termite mounds in the fields was the most commonly reported control method. Salt and other pesticides were commonly used by farmers to protect stored farm products. The lack of effective control methods is the main constraint for termite management. In northwestern Benin, farmers reported different purpose utilizations of termite mounds and termites. Conclusions The study has shown that farmers perceived termites as pests of several agricultural crops and apply various indigenous control practices whose efficiency need to be verified. Utilization of termites and termite mound soil as food and medicinal resources underlines the need for a more focused approach to termite control for the conservation of non-pest termite species. The sensitization of farmers on the importance of termites as well as the development of an integrated control method to combat termite pests proved necessary.

Taro (Colocasia esculenta L. Schott) and tannia (new cocoyam) (Xanthosoma mafaffa L. Schott) are food crops cultivated in tropical and subtropical regions of Asia, Africa and Latin America. In cultivation, they are always vegetatively propagated and their production faces many constraints. Their corm is an important source of carbohydrates and leaves eaten as vegetable provide important minerals and vitamins. In Togo, although these crops are among the most important food crops in some rural areas, they appear at the country level as neglected and underutilized species (NUS) and should be promoted. However, adequate information related to production, constraints, farmers' preferred traits and utilisation is lacking for the development of efficient breeding schemes and their sustainable preservation and use in Togo. In this paper, a focus group survey was conducted in all five ecological zones of the country to document farmers' perceptions regarding constraints for production of these two crops and their preferred traits for production and utilization. Collected data were analysed through descriptive statistics (frequencies, percentages and means) using the Statistical Package for Social Scientists (SPSS 20) and Excel spreadsheets. Rainfall irregularity (or shortage of rainy seasons) (68.4% of responses), soil infertility (61.5% of responses) and inefficient marketing (58.7% of responses) were the most common production constraints reported. Farmers preferred early-maturity (73% of responses) and high-yield (65% of responses) as crop traits. Men are more involved in production of these crops in Togo (79% of respondents). However, the constraints and preferences reported were not gender dependent. This study showed that production of taro and tania faces many challenges in Togo. Morphological and molecular characterization of grown varieties is highly recommended to help select suitable varieties for breeding programmes. Improvements in food processing and accessibility of credit should be prioritized to generate more income for farmers and encourage production in Togo.Key words: Agriculture, Colocasia esculenta, constraints, farmers, preferences, production, Togo, Xanthosoma mafaffa, INTRODUCTIONIn 2005, FAO estimated that 852 million persons, particularly in developing countries suffer from chronic malnutrition. For example, in Togo, the annual mean growth of food supply is 3.1% for [...]

Abstract Background After cereals, root and tuber crops are the main source of starch in the human diet. Starch biosynthesis was certainly a significant target for selection during the domestication of these crops. But domestication of these root and tubers crops is also associated with gigantism of storage organs and changes of habitat. Results We studied here, the molecular basis of domestication in African yam, Dioscorea rotundata. The genomic diversity in the cultivated species is roughly 30% less important than its wild relatives. Two percent of all the genes studied showed evidences of selection. Two genes associated with the earliest stages of starch biosynthesis and storage, the sucrose synthase 4 and the sucrose-phosphate synthase 1 showed evidence of selection. An adventitious root development gene, a SCARECROW-LIKE gene was also selected during yam domestication. Significant selection for genes associated with photosynthesis and phototropism were associated with wild to cultivated change of habitat. If the wild species grow as vines in the shade of their tree tutors, cultivated yam grows in full light in open fields. Conclusions Major rewiring of aerial development and adaptation for efficient photosynthesis in full light characterized yam domestication.

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.

L’igname est une culture stratégique au Togo. L’inventaire des variétés cultivées dans différents agro-éco-systèmes traditionnels permettent la sauvegarde et de ce patrimoine génétique ainsi que son utilisation dans des programmes de sélection. Des enquêtes ethno-botaniques ont été conduites dans 30 localités de la région de la Kara a permis de recenser 134 variétés: 122 de D. cayenensis-D. rotundata (57% précoces et 43 % tardives) et 12 de D. alata. La richesse variétale par localité varie de 7 à 30 variétés avec une moyenne de 19 ± 6 et une prédominance de D. cayenensis-D. rotundata. Dans 22% des localités, la diversité variétale a augmenté du fait des introductions (19 %) du Bénin (52 %), du Ghana (40 %) et du Nigeria (8 %). Les acquisitions variétales se font par achat (72 %), héritage (65 %), échange (45 %) et don (35 %). L’adoption d’une variété est déterminée par des critères agronomiques, commerciaux, technologiques, socio-culturels. Dans 78 % des localités, il y a une réduction de la diversité variétale du fait des pressions économiques, technologiques et sociales. 82 % des variétés sont faiblement distribuées et nécessitent une action urgente de conservation au champ. Cette conservation peut se faire dans 9 localités qui abritent 80 % de la richesse variétale totale. Mots clés: Ignames, perte de variétés, érosion génétique, conservation, Togo.

Yams (Dioscorea spp.) are one of the food crops that contribute to food security and poverty alleviation in Benin and, like several other products, the post-harvest phase is threatened by the rotting of fresh tubers. To overcome this constraint, yam tubers are traditionally processed into dried chips which unfortunately are severely attacked by Dinoderus porcellus Lesne (Coleoptera: Bostrichidae). Research studies on relative resistance of dried chips of 24 yam landraces to the attack of D. porcellus during storage were carried out using free-choice tests (antixenosis) and non-choice tests under laboratory conditions. Attractiveness of yam chips, mortality of initial pest populations, weight loss, and also the Dobie’s index of susceptibility were considered as indicators of resistance. The results revealed that the landraces Boniwouré and Wonmangou were significantly less attractive and consumed by D. porcellus. The highest mortality rate of D. porcellus was observed on the landrace Boniwouré followed by Alahina. Based on the Dobie index of susceptibility five yam landraces (Gaboubaba, Boniwouré, Alahina, Yakanougo, and Wonmangou) were scored as resistant to D. porcellus. All the remaining landraces were categorized as moderately resistant. Based on the present study, these five resistant landraces deserve special consideration and may be recommended for relatively longer storage to achieve the goal of sustainable management of D. porcellus.

Dinoderus porcellus is considered as the most important pest of stored yam chips and compounds extracted from plants can be used for its control. The present study aimed to test the insecticidal and repellent activities of powders and extracts of leaves of Bridelia ferruginea, Blighia sapida, and Khaya senegalensis against D. porcellus. The efficacy of plant powders was compared with the synthetic pesticide Antouka (Permethrin 3 g/kg + pirimiphos 16 g/kg). The results of the experiment revealed that all plant powders were effective as repellents. Antouka was more effective as insecticidal than the plant powders and minimal weight loss was observed with B. sapida at 2%. Among treatments, propanol extract of K. senegalensis at 5% was found to elicit the highest repellent effect on D. porcellus. The LC50 results revealed that the acetone extract of K. senegalensis is the most toxic (0.29 μL/insect) to the pest, while the propanol extract of B. ferruginea at 5% exhibited strong fumigant toxicity against D. porcellus, with 88.89% of pest mortality at 160 μL/L air. The findings from the current work proved that plant powders and extracts of the three plants are sources of botanical insecticides which may be used in the integrated management of D. porcellus.