142 research outputs found
Sélection de sites pour la conservation in situ des ignames sauvages apparentées aux ignames cultivées : cas de Dioscorea praehensilis au Bénin
Dioscorea praehensilis est une igname sauvage apparentĂ©e aux ignames cultivĂ©es du complexe D. cayenensis-D. rotundata qui Ă©volue en populations naturelles dans les forĂȘts du Sud et du Centre-BĂ©nin. Pour identifier les sites propices Ă la prĂ©servation in situ de ses populations naturelles et de sa diversitĂ© gĂ©nĂ©tique, six forĂȘts du sud et du centre BĂ©nin (Agoua, Ahozon, EwĂš, KĂ©tou, Lama et Niaouli) ont Ă©tĂ© prospectĂ©es. Les forĂȘts de la Lama, dâEwĂš et de Niaouli sont les plus riches en D. praehensilis avec, respectivement, des densitĂ©s moyennes de 109, 63 et 59 pieds/ha. Type de vĂ©gĂ©tation, Ă©clairement, type de sol, pressions anthropiques et animales sont les facteurs qui influencent la densitĂ© de lâespĂšce dans les formations vĂ©gĂ©tales prospectĂ©es et ont permis de reprĂ©ciser son Ă©cologie. Sur la base de la densitĂ© de lâespĂšce et de son importance pour les populations riveraines, de lâimportance de la pression anthropique et animale, du degrĂ© dâimplication de la population dans la conservation des forĂȘts, de la richesse des forĂȘts en espĂšces de Dioscorea importantes ou rares, de lâĂ©tat actuel de conservation de la forĂȘt et de lâexistence d'un plan d'amĂ©nagement, les forĂȘts classĂ©es de la Lama et de Niaouli ont Ă©tĂ© identifiĂ©es comme les meilleurs sites pour la conservation in situ de D. praehensilis au Benin. Du fait de sa richesse secondaire en lâespĂšce D. burkilliana devenue trĂšs rare, la dotation de la forĂȘt dâAhozon dâun plan dâamĂ©nagement et de gestion participative a Ă©tĂ© proposĂ©e. © 2013 International Formulae Group. All rights reserved.Mots clĂ©s : BĂ©nin, conservation, Dioscorea praehensilis, igname sauvage, forĂȘts classĂ©e
Caractérisation agromorphologique des variétés de niébé cultivées au Bénin
Le niĂ©bĂ© (Vigna unguiculata (L.) Walp.) est une lĂ©gumineuse trĂšs cultivĂ©e et consommĂ©e au BĂ©nin. Sa diversitĂ© reste encore peu connue et lâutilisation des variĂ©tĂ©s traditionnelles disponibles Ă des fins de sĂ©lection exige une bonne connaissance de leurs caractĂ©ristiques agronomiques, technologiques et culinaires. Pour cette raison, 124 variĂ©tĂ©s traditionnelles collectĂ©es dans diffĂ©rentes localitĂ©s ont Ă©tĂ© Ă©valuĂ©es sur la base de 11 variables quantitatives et 12 variables qualitatives dans un dispositif de blocs complĂštement alĂ©atoire (BCA) Ă trois rĂ©pĂ©titions. Parmi les caractĂšres qualitatifs, la collection analysĂ©e fait montre dâune importante variabilitĂ© (42 morphotypes) pour le port de la tige, la pigmentation de la plante, la couleur des fleurs, la forme des folioles, la couleur des gousses, la taille, la couleur et la formes des graines. Lâanalyse en composante principale (ACP) des variables quantitatives a rĂ©vĂ©lĂ© 4 groupes au sein de la collection dont le groupe (G1) rassemble la plupart des variĂ©tĂ©s trĂšs performantes (cycle court, nombre de gousses Ă©levĂ© par plante, grains gros et lourds, rendements supĂ©rieurs Ă 2 tonnes Ă lâhectare) comme CatchĂ© godonou, Ewaoloy, GbolĂ©kpomin, Kaki et Yanbodo quâon peut utiliser dans les programmes de sĂ©lection. Une corrĂ©lation positive significative est observĂ©e entre le rendement par plante de niĂ©bĂ© et le nombre de gousses par plant (Ngs), la longueur des gousses (LGs) et le poids de 100 graines (P100G). Ces donnĂ©es exploitables pour la sĂ©lection de variĂ©tĂ©s amĂ©liorĂ©es et la gestion des ressources gĂ©nĂ©tiques du niĂ©bĂ© doivent ĂȘtre encore complĂ©tĂ©es par lacaractĂ©risation molĂ©culaire.Mots clĂ©s : BĂ©nin, diversitĂ©, niĂ©bĂ©, rendement, variabilitĂ© morphologique
Connaissances endogĂšnes et perceptions paysannes de lâimpact des changements climatiques sur la production et la diversitĂ© du niĂ©bĂ© (Vigna unguiculata (L.)Walp.) et du voandzou (Vigna subterranea (L) Verdc.) au BĂ©nin
Lâexistence dâimpacts nĂ©fastes du changement climatique sur la production agricole en Afrique subsaharienne est maintenant solidement Ă©tablie. Pour documenter les connaissances endogĂšnes relatives au changement climatique, identifier les contraintes qui y sont associĂ©es et qui affectent la production et la diversitĂ© du niĂ©bĂ© et du voandzou au BĂ©nin et examiner les stratĂ©gies adaptatives localement utilisĂ©es, 40 villages sĂ©lectionnĂ©s dans diffĂ©rentes zones agroĂ©cologiques du BĂ©nin ont Ă©tĂ© prospectĂ©s. Des mĂ©thodes dâanalyses qualitatives et quantitatives ont permis de comprendre que les attaques des insectes aux champs et au cours de stockage restent les contraintes prioritaires. Lâanalyse du choix des mĂ©thodes dâadaptation face aux changements climatiques a montrĂ© que lâĂąge du producteur de niĂ©bĂ© affecte de façon positive lâadoption des pratiques culturales (p<0,05) et des stratĂ©gies multiples (p<0,1) ; le sexe influence de façon significative (p<0,001) mais nĂ©gative le choix des producteurs de voandzou Ă utiliser des variĂ©tĂ©s rĂ©sistantes et de multiples stratĂ©gies. Le nombre de manoeuvres utilisĂ© par ces producteurs influence de façon significative le choix de multiples stratĂ©gies (p<0,001). Des programmes nationaux de lutte contre les effets liĂ©s aux changements climatiques sont Ă mettre en place afin de prĂ©server les ressources gĂ©nĂ©tiques de niĂ©bĂ© et du voandzou au BĂ©nin.© 2015 International Formulae Group. All rights reserved.Mots clĂ©s: BĂ©nin, contraintes, changement climatique, pratique culturale, niĂ©bĂ©, voandzouEnglish Title:  Endogenous knowledge and farmersâ perceptions of the impact of the climatic changes on the production and the diversity of cowpea (Vigna unguiculata (L.) Walp.) and Bambara groundnut (Vigna subterranea (L.) Verdc.) in BeninEnglish AbstractThe existence of harmful impacts of climate change on the agricultural production in sub-Saharan Africa is now firmly established. To document endogenous knowledge relating to the climate change, to identify the constraints which are associated to it and which jeopardize the production and the diversity of cowpea and Bambara groundnut in Benin and to examine the adaptive strategies locally used, 40 villages selected in various agro ecologic areas from Benin were surveyed. Methods of qualitative and quantitative analyses made it possible to understand that the attacks of insects to the fields and during storage remain the priority constraints. The analysis of the choice of the methods of adaptation as regards to the climate changes showed that the age of the producer of cowpea affects in a positive way the adoption of the cultivation methods (p<0.05) and multiple strategies (p<0.1); the sex influences to a significant degree (p<0,001) but negative the choice of the producers of Bambara groundnut to use resistant varieties and multiple strategies. The number of operations used by these producers influences to a significant degree the choice of multiple strategies (p<0,001). National programs to struggle against the effects related to the climatic changes are to be set up in order to preserve the genetic resources of cowpea and Bambara groundnut in Benin.© 2015 International Formulae Group. All rights reserved.Keywords: Benin, Bambara groundnut, constraints, climate change, cowpea, practical farmin
The âBringing into Cultivationâ Phase of the Plant Domestication Process and Its Contributions to In Situ Conservation of Genetic Resources in Benin
All over the world, plant domestication is continually being carried out by local communities to support their needs for food, fibre, medicine, building materials, etc. Using participatory rapid appraisal approach, 150 households were surveyed in 5 villages selected in five ethnic groups of Benin, to investigate the local communities' motivations for plant domestication and the contributions of this process to in situ conservation of genetic resources. The results indicated differences in plant domestication between agroecological zones and among ethnic groups. People in the humid zones give priority to herbs mainly for their leaves while those in dry area prefer trees mostly for their fruits. Local communities were motivated to undertake plant domestication for foods (80% of respondents), medicinal use (40% of respondents), income generation (20% of respondents) and cultural reasons (5% of respondents). 45% of the species recorded are still at early stage in domestication and only 2% are fully domesticated. Eleven factors related to the households surveyed and to the head of the household interviewed affect farmers' decision making in domesticating plant species. There is gender influence on the domestication: Women are keen in domesticating herbs while men give priority to trees
Possibilities of sweet potato [Ipomoea batatas (L.) Lam] value chain upgrading as revealed by physico-chemical composition of ten elites landraces of Benin
Sweet potato is one of the most important food security promoted root crops in the world, especially in sub-Saharan Africa. Unfortunately, the crop is still neglected and underutilized in Benin Republic. To establish baseline data for its better utilization for upgrading its value chain, 10 selected local varieties (01 cream, 02 white, 03 yellow, and 04 orange flesh-colored) were compared for their macro-nutritional composition assessed using standard Association of Official Analytical Chemists (AOAC) procedures and spectrophotometry methods. The results indicate that sweet potato dry matter, protein, fiber, and ash content ranged from 46.11 to 25.9%, 4.09 to 1.97%, 1.81 to 3.00%, and 4.70 to 2.56%, respectively and orange flesh cultivars were found very rich. Pearson correlation analysis of variables revealed that dry mater content is positively correlated with carbohydrate and energy values, but negatively correlated with ash and fiber content, while starch content is strongly correlated with fiber content. Principal component analysis allowed us to classify the sweet potato varieties into 03 varietal groups among which Group 2 (05 varieties) exhibited rich fiber, ash, and protein contents and may be recommended for infant foods formulations. These results constitute important orientation for sweet potato processing chain organization in Benin and for the establishment of future nutrition and breeding programme.Key words: Benin, sweet potato, Ipomoea batatas, nutritional composition, orange flesh cultivar, value chain
Diversité et évaluation participative des cultivars du manioc (Manihot esculenta Crantz) au Centre Bénin
Le manioc est une plante alimentaire qui contribue fortement Ă la sĂ©curitĂ© alimentaire au BĂ©nin. Pour Ă©valuer sa diversitĂ© variĂ©tale, les performances agronomiques, technologiques et culinaires de ses cultivars dans la rĂ©gion centrale du BĂ©nin, 41 villages ont Ă©tĂ© prospectĂ©s. Sous rĂ©serve de synonymie, 107 cultivars de manioc ont Ă©tĂ© recensĂ©s dont 59 Ă©lites. Lâindice de diversitĂ© de Shannon est de 3,78 et traduit une importante diversitĂ© variĂ©tale. Le nombre de cultivars recensĂ©s varie de 3 Ă 26 par village (10 en moyenne). Dans les villages oĂč une perte de diversitĂ© variĂ©tale est notĂ©e, son taux a variĂ© de 6,25 Ă 80% avec un taux moyen de 42,22% par village. Les cultivars Ă produire sont choisis sur la base de 21 critĂšres dont les plus importants sont la forte productivitĂ© (16,37% de reponses), la qualitĂ© et le rendement en gari (15,52% de reponses) et la prĂ©cocitĂ© (13,27% de reponses). Les contraintes de production (9 au total) perçues par les producteurs peuvent etre levĂ©es par lâutilisation des cultivars performants. LâĂ©valuation participative a rĂ©vĂ©lĂ© lâexistence de trĂšs peu de cultivars performants par rapport aux paramĂštres biotiques et abiotiques. La mise en place dâun programme dâamĂ©lioration et de crĂ©ation variĂ©tale est fortement recommandĂ©e pour la relance de la production du manioc au BĂ©nin.Mots clĂ©s : BĂ©nin, critĂšre de prĂ©fĂ©rence, cultivar Ă©lite, diversitĂ© variĂ©tale, Ă©valuation participative, manioc
Proximate, mineral and vitamin C composition of vegetable Gbolo [Crassocephalum rubens (Juss. ex Jacq.) S. Moore and C. crepidioides (Benth.) S. Moore] in Benin
Gbolo (Crassocephalum crepidioides and Crassocephalum rubens) is a traditional leafy vegetable highly consumed in southern and central Benin, as well as in some part of northern Benin. The nutritional potential of the two species of Gbolo were evaluated through their proximate composition, mineral and vitamin C profile using recommended AOAC method of analysis. The analysis revealed that the contents in raw protein, total lipids, ash and carbohydrates expressed in % of dry matter were 27.13±0.01%,3.45± 0.00%,19.02± 0.01%and 42.22 ± 0.04% for C. crepidioides; 26.43± 0.01%, 2.75± 0.01%, 19.76± 0.05% and 43.11±0.10 % for C. rubens respectively. The content of vitamin C for 100g of fresh leaf is of 9.17 mg for C. crepidioides and 3.60 mg for C. rubens. The moisture content (% of cool matter) and the total metabolizable energy (kcal/100 g of dried matter) were respectively 86.79± 0.04 %and 308.45 ± 0.28 for C. crepidioides and 87.95% ± 0.07 %and 302.91 ± 0.56 for C. rubens. The result of the mineral composition indicated that the sodium (Na), potassium (K), phosphorus (P), magnesium (Mg), calcium (Ca), iron (Fe), Manganese (Mn) and Copper (Cu) contents were higher in C. rubensthan in C. crepidioides. With regard to the obtained values, the Gbolo vegetable showed a satisfactory composition and a significant variability between the mineral salts in its two species and can be valorised for a balanced nutrition of populations. Efforts should be made for the promotion of its wide cultivation and consumption. © 2013 International Formulae Group. All rights reserved.Keywords: Benin, Crassocephalum, Gbolo, mineral composition, proximate composition, vitamin C
Perceptions paysannes et impacts des changements climatiques sur la production et la diversitĂ© variĂ©tale de lâigname dans la zone aride du nord-ouest du BĂ©nin
Lâigname (Dioscorea spp.) est une culture vivriĂšre de grande importance pour la sĂ©curitĂ© alimentaire au BĂ©nin. Cependant, sa production dans le dĂ©partement de lâAtakora (extrĂȘme Nord-Ouest) est sĂ©rieusement affectĂ©e par les changements climatiques. Pour analyser les perceptions paysannes des changements climatiques, documenter les impacts de ceux-ci sur la production des ignames et les stratĂ©gies d'adaptation dĂ©veloppĂ©es pour y faire face, quinze (15) villages ont Ă©tĂ© sĂ©lectionnĂ©s au hasard et explorĂ©s. Les producteurs ont signalĂ© des fluctuations de tempĂ©rature et de pluviomĂ©trie, une augmentation de la tempĂ©rature et une diminution de la pluviomĂ©trie corroborĂ©es par lâanalyse des donnĂ©es mĂ©tĂ©orologiques. LâĂąge et le genre influencent significativement la perception paysanne des changements climatiques. Les impacts les plus importants sont la baisse de rendement, la pourriture des tubercules et des semences, lâappauvrissement et la dĂ©gradation des sols et la prolifĂ©ration des insectes et ravageurs. Les stratĂ©gies adoptĂ©es inclus entre autres le paillage des buttes, le dĂ©placement vers les zones humides et lâutilisation de bonnes pratiques culturales et de la diversitĂ© variĂ©tale. Cette capacitĂ© dâadaptation des producteurs pourrait ĂȘtre accompagnĂ©e par les politiques publiques mais ceux-ci devront tenir compte des diffĂ©rents facteurs influençant la capacitĂ© dâadaptation des producteurs dĂ©terminĂ©s au cours de cette Ă©tude.Mots clĂ©s : CritĂšres de prĂ©fĂ©rence, cultivars tolĂ©rants, sĂ©cheresse, stratĂ©gies dâadaptation, variabilitĂ© climatique
Combining High Yields and Blast Resistance in Rice (Oryza spp.): A Screening under Upland and Lowland Conditions in Benin
The future security of the supply of rice for food in Africa depends on improving the level of local production to achieve self-sufficiency. In order to cope with the existing gap between production and actual demand, combining a high level of rice blast tolerance and a high-yield potential is necessary. The current study was conducted under upland and lowland conditions in Benin to gain insight into the performance of selected blast-resistant accessions along with some currently grown varieties. This study revealed a high phenotypic variability among these accessions. Furthermore, differences in the performance of these accessions under lowland and upland conditions were observed. Principal component analysis showed their grouping in three clusters. The analysis also demonstrated a high yield potential among the blast-resistant rice accessions whether they were Oryza sativa or O. glaberrima. Furthermore, there was a significant correlation between yield and both spikelet fertility and growth cycle duration. In conclusion, the present study identified promising rice accessions for future breeding. High phenotypic variability in combination with interesting traits can help to develop new resilient varieties. Finally, when the traits correlate with yield, they can be used as markers for an early screening method for identifying promising accessions at an early stage
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