Agro-morphological and structural diversity of rice germplasm revealed by SSR markers in Benin Republic.

BACKGROUND: In developing countries, rice is a staple food and cash crop for the people. In Benin Republic, paddy rice production has increased over time. Accordingly, local varieties were replaced by improved varieties, leading unfortunatley to a loss of the diversity of Beninese rice germplasm. METHODS AND RESULTS: The investigation focused on the structure and genetic diversity of 72 rice accessions collected throughout 22 villages using 13 quantitative traits and 17 SSR markers. The descriptive analysis of the 13 quantitative parameters showed a significant difference among the accessions, with a grouping in three clusters. Group I (16.66% of samples) was composed of accessions with long, wide and thick grains alongside with four controls TOG5681, TOG5307, Azucena and Moroberekan. Group II (7% of samples) contained accessions with late vegetative cycle. Group III contained most of the accessions (76.39% of the samples), including accessions such as the CG14 and Nipponbare control lines, and almost all the improved varieties. The molecular analysis revealed a significant diversity (mean number of alleles: 4.47 with polymorphism information content of 0.633). Population structure based on molecular markers showed three primary populations with a mixture of phenotypic groupings at ΔK, K = 3. CONCLUSION: This study showed that Beninese rice germplasm was divided into two structures: phenotypically similar cultivars but genotypically distinct (homonyms), and phenotypically different cultivars but genotypically similar (synonyms). Some local cultivars such Bagou19, Bagou20 and Koud44 can be used for large scale production due to their agronomics and molecular traits. The molecular structure obtained in this investigation might be used for future conservation and breeding programs.

Impact of Seed Origin and Genetic Drift of Improved Rice Variety IR841 in Benin.

BACKGROUND: Rice production is important for food security in Benin, with a national production largely dominated by the cultivation of the aromatic ecotype IR841, by far the most appreciated by Beninese consumers. However, to maintain agronomical qualities of a given cultivar, the origin and quality of seeds are mandatory and at the heart of the maintenance of yield and of market requests. Following this idea, the objective of the current study was thus to investigate the genetic purity of IR841 varieties collected from rice producers across 22 villages in Benin in relation to their agronomical performances. RESULTS: For this, agromorphological evaluation of 72 accessions based on 13 quantitative descriptors followed by genotyping with the Illumina Infinium rice 7 K SNP array of 9 accessions was carried out in the presence of 2 controls. Agromorphologic as well as genetic and phylogenetic analyses revealed two groups, the first one Okouta97, Koum47, Nana30, Man118, Ang1 and control sample IR841-2) was characterized by seed accessions provided by the formal seed system, while the second (Koum53, Tchaka41 and Koud46) comprising seeds from local markets or from previous harvests and showing a depression in agronomic performances. CONCLUSION: We showed that IR841 seed purity is mandatory for the completion of agronomical performance, and that the farmers' choice of seeds must be guided and informed to ensure sustainability and food security.

Characterization of rice farming systems, production constraints and determinants of adoption of improved varieties by smallholder farmers of the Republic of Benin.

The identification of technological and policy interventions allowing to improve the performance of Beninese rice systems is necessary to reduce the heavy dependence on rice imports. This study characterized the Beninese rice farming systems, identified the production constraints, and determinants of the adoption of improved varieties by farmers. Four hundred eighteen rice farm households were surveyed across 39 villages using participatory research tools and methods. Cluster analysis was used to classify the surveyed farm households and revealed four typologies of rice farming systems differentiated by 8 variables. These are, the intensive rice farming system (cluster 4; 33.7%), semi-intensive rice farming system (cluster 1; 31.8%), integrated rice-livestock farming system (cluster 3; 11.8%), and subsistence rice farming (cluster 2; 22.7%). The integrated rice-livestock farming system was the dominant type practiced in the northern Benin, while, it is the intensive rice farming system in the south. Fifteen production constraints across rice-growing areas were recorded. Our results suggest that to increase adoption of improved rice varieties, agricultural extension services should target landowners' farmers practicing off-season rice production, and having other sources of income. Initiatives to boost rice production in Benin should prioritize the establishment of formal agricultural credit and mechanization option policies.

Rice pests in the Republic of Benin: farmers' perceptions, knowledge and management practices.

BACKGROUND: Rice (Oryza spp) is one of the most consumed cereals in the Republic of Benin. However, rice production is threatened by various pests, which lead to important yield losses. For the development of integrated management strategies responding to the farmers' realities, it is important to document their perceptions, knowledge and management of rice pests. Surveys involving 418 rice farmers to 21 ethnic groups through 39 villages were performed using rural appraisal tools. RESULTS: Farmers perceived birds, specifically weavers as the most important rice pests. The surveyed farmers also identified the variegated grasshopper, Zonocerus variegatus L. and rice brown leaf spots [Curvularia lunata (Wakker) Boedijn] as the main pests in the northern region, the pink stem borer, Sesamia calamistis Hampson and rice blast (Magnaporthe grisea (Hebert) Barr) in the southern region, and Z. variegatus and rice yellow mottle virus (genus Sobemovirus) in central Benin. The most important rice storage constraint was rodent attacks and the surveyed farmers proposed 13 key solutions to minimize constraints related to rice storage. Among various pest control methods recorded, farmers used mainly synthetic chemical pesticides. However, the Beninese National Pesticide Management Committee (CNGP) does not recommend most of pesticides used by farmers for rice protection (prohibited pesticides or intended for the protection of other crops). Farming experience, family size, region and number of observed pests have significantly influenced farmers' decision to use pesticides. CONCLUSION: The rice pests perceived by farmers as important vary significantly across regions. These results suggest that integrated pest management programmes which target rice pests accounting for these regional differences will be more effective. The identified variables that influence the use of pesticides must be taken in account in the development of strategies which will encourage farmers to use ecofriendly pest management.

Traditional knowledge of invertebrates used for medicine and magical-religious purposes by traditional healers and indigenous populations in the Plateau Department, Republic of Benin.

BACKGROUND: Since ancient times, invertebrates have played an important role in the traditional medicine in many parts of the world. In south-eastern Benin, more specifically in the Plateau Department, invertebrates are widely used in folk medicine. However, studies on their therapeutic use has been neglected and their magical-religious purposes are poorly understood. The present study aims to document traditional knowledge related to the use of invertebrates for medicinal and magical-religious purposes by traditional healers and indigenous people of Plateau Department. METHODS: An ethno-sociological survey was conducted with 145 informants (80 traditional healers, 12 merchants of medicinal animals and 53 households) belonging to six ethnic groups, in 20 villages located in Plateau of Benin. Data were collected through the participatory rural appraisal method involving individual interviews and direct observations with semi-structured questionnaires. The collected data regarding various medicinal and magical-religious uses of invertebrates were analysed through informant consensus factor (ICF), use value (UV) and, fidelity level (FL). RESULTS: A total of 20 families and 38 species of invertebrates, distributed among 6 taxonomic categories, were found to be used to treat 50 different ailments. Insects occupied 64.7% of the total invertebrates listed. The African earthworm Eudrilus eugeniae K. and African giant snail Achatina achatina L. had the highest use values. The highest ICF value (1.0) was cited for diseases of the blood or blood-forming organs. A principal component analysis (PCA) revealed the influence of ethnic groups in the diseases treated with invertebrates. The highest FL (100%) was recorded for 12 invertebrate species treating various ailments. Most of invertebrate-based remedies were associated with plant species. The mode of administration was mainly oral and topical. Most of the invertebrate drugs were traditionally collected in nature or imported, mainly from Nigeria. In addition, 7 magical-religious practices are documented. CONCLUSIONS: Our results reveal that several invertebrate species play an important role in healing practices and magical-religious rituals in the Plateau Department. We suggest further studies to confirm the presence of any bioactive compounds on invertebrate species use in traditional medicine. In addition, this study highlights the need for ecological investigations of these species, in order to develop strategies for their conservation and sustainable use.

Folk taxonomy and traditional uses of common bean (Phaseolus vulgaris L.) landraces by the sociolinguistic groups in the central region of the Republic of Benin.

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.

Farmers' perception of termites in agriculture production and their indigenous utilization in Northwest Benin.

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.

Diversity, Physicochemical and Technological Characterization of Elite Cassava (Manihot esculenta Crantz) Cultivars of Bantè, a District of Central Benin.

Cassava is one of the staple food crops contributing significantly to food and nutrition security in Benin. This study aimed to assess the diversity of the elite cassava cultivars of Bantè district, determine the physicochemical properties of the most preferred ones as well as the sensory attributes of their major derived products (gari and tapioca), and compare them with the farmers' and processors' perception on their technological qualities. The ethnobotanical investigation revealed existence of 40 cultivars including 9 elites that were further classified into three groups based on agronomics and technological and culinary properties. Clustered together, cultivars Idilèrou, Monlèkangan, and Odohoungbo characterized by low fiber content, high yield of gari and tapioca, and good in-ground postmaturity storage were the most preferred ones. Their physicochemical analysis revealed good rate of dry matters (39.8% to 41.13%), starch (24.47% to 25.5%) and total sugars (39.46% to 41.13%), low fiber (0.80% to 1.02%), and cyanide (50 mg/kg) contents. The sensory analysis of their gari and tapioca revealed very well appreciated (taste, color, and texture) products by the consumers. The confirmation by scientific analysis of the farmers' perception on qualities of the most preferred cultivars indicated that they have good knowledge of their materials.