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Background: The CpG island methylator phenotype(CIMP)with extensive promoter methylation isa distinct epigenotype incolorectal cancer (CRC). Changes in microbiota and epigenetic dysregulation might be the key underlying mechanism.Methods: Tissues with stages I–III cancer were collected after proctocolectomy. The 16S rRNA gene sequencing was carried to determine the differences in microbiota. Subsequently, BRAF mutation, the status of microsatellite instability (MSI, also known as mismatch repair deficiency) and CIMP were also tested. The Chi-square test was carried out to analyze the relationship between molecular changes (MSI and CIMP) and the development of CRC.Results: Patients in the three groups differed in thetumorlocation(P=0.034) and the carcinoembryonic antigen (CEA) level (P=0.036).The positive CIMP and MSI-LOW/MSS were more common in the worse prognosis groups. The Kaplan–Meier and Cox proportional regression analyses indicated that CIMP and MSI were the independent indicators of poor survival since the positive rates of which were significantly higher in the non-survival group. Besides, there were differences in microbiota among tumor tissues of different prognoses, with the Fusobacterium nucleatum and Bacteroides fragilis more abundant in the worse prognosis groups.Conclusion: The persistent epigenetic changes influence the prognosis of patients with CRC and the composition of the gut microbiota might be the cause.

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.

Background Peanut ( Arachis hypogaea L.) is one of the major oilseed legumes contributing to food security and poverty reduction in Benin. Unfortunately, several constraints hamper peanut production in Benin leading to a low yield. Knowing that seed is crucial for increase agricultural productivity, a good knowledge of on-farm management of grown peanut diversity and uses that allow its maintenance in traditional Beninese agriculture are prerequisites to establish an efficient breeding and conservation programs. Therefore, this study aim to document peanut varietal diversity, folk nomenclature, seed system, storage constraints, seeds pest management practices, varietal preference criteria, cultural taboos and uses in southern and central Benin. Methods Two hundred and sixteen (216) farmers were surveyed through 32 villages in southern and central Benin using research tools and techniques of rural appraisal such as field visits, group surveys and individual surveys using a questionnaire. Results Fifty-four peanut folk varieties grouped into 8 morphotypes based on the seed characteristics were registered in the study area. All local names given to peanut folk varieties by ethnic groups have meaning. The number of folk varieties maintained per village ranged from 1 to 11 (an average of 4) and varied between 1 and 4 per household. Some peanut producers reported the disappearance of some folk varieties. The drop in yield was the main reason of peanut varietal disappearance in the study area. Rodent attacks were the most important constraints of peanut production in the study area. Varietal preference criteria varied from ethnic groups with seed size and many pod/seeds per plant as the main preferred traits. Peanut seed system was mainly informal. For peanut seed conservation, farmers use various storage tools. To alleviate pest problems in stored peanut, producers used plant biocides and synthetic chemicals. Some cultural taboos and various uses (food, feed and medicinal) of peanuts have been recorded in the southern and central Benin. Conclusions Our results suggest that for boost peanut production in central and southern Benin, breeders must create high yielding peanut varieties. For the adoption of these new varieties, it is important to take in account the preference varietal criteria of each ethnic group. To a good estimation of peanut diversity in the study area, morphological and molecular characterizations were recommended.

In Benin, stored yam chips are severely attacked by Dinoderus porcellus Lesne which causes important losses. The use of medicinal plants combined with the insect-resistant yam chips can be an efficient alternative of chemical insecticides for yam chips protection. This study aims to evaluate an integrated pest management of D. porcellus using combined effects of resistant yam chips (Boniwoure, Gaboubaba, Wonmangou, and Yakanougo landraces) and leaves powder of Bridelia ferruginea Benth, Blighia sapida Juss and Khaya senegalensis Cronquist. For that, repellence, weight loss, mortality and progeny production were evaluated with Antouka commercial insecticide as positive control and untreated yam chips as negative control. The results revealed that all treatments are strongly repellent and showed important reproductive inhibition rate and remarkable inhibition of emergency of D. porcellus progeny. The weight loss due of yam chips treated with the three medicinal plants was not significantly different from those treated with Antouka, but significantly different from untreated yam chips. Only K. senegalensis at 2% (w/w) combined with Wonmangou landrace was able to achieve 66.2% of mortality after 21 days of experimentation. Hence, combination of resistant yam chips with leaves powder of these three medicinal plants could be promoted for integrated management of D. porcellus. Key words: Dinoderus porcellus, integrated pest management, medicinal plants, resistance varietal, storage, yam chips.

Common bean (Phaseolus vulgaris L.) is a legume that contributes to food security and poverty reduction in Benin. However, there is very little information on its production constraints, varietal diversity, storage practices, storage insect management, and seed system. While these information are necessary for use in breeding programs and a better conservation of this legume. To fill these gaps, ethnobotanical surveys were conducted in 23 villages selected through central Benin using participatory rural appraisal tools and techniques. The number of beans landraces ranged from 3 to 5 per village (4.7 on averages) and from 1 to 4 per household (1.7 on average). A total of 26 common beans folk varieties, corresponding to 12 climbing bean landraces were recorded in the study area. A high rate of threat of landraces disappearance was recorded through surveyed villages. Various seeds storage tools were recorded and the seed system was essentially informal. The use of inert substances, chemical insecticides and insect repellent/insecticidal plants to control storage insects has been reported in the study area. Farmers noted a differential susceptibility of common bean landraces to storage insect pest. Our findings showed that there is an urgent need of development of integrated bean storage insect management strategies. Key words: Constraints, common bean, insect pests, seed system, varietal diversity.

Corchorus olitorius L. is one of the traditional leafy vegetables of high food and socio-economic value in Africa. Although widely exploited, its varietal diversity is unknown and its domestication remains challenged by pests and diseases presently observed among subsistence users. This study aims to determine the morphotype diversity of C. olitorius in Southern Benin and the durability of its agroecosystem by the influence of agricultural practices on the major pest insects related to its production. Using participatory research methods, surveys were conducted in 21 villages randomly selected across the study area. Results revealed seven different morphotypes of C. olitorius, three of which were wild but used in traditional medicine and four were cultivated. Among the nine constraints reported by farmers, the attack of seven pest insects and the non-distinction of the seeds of the different cultivated morphotypes are the two most important constraints. The seven most common potential pest insects observed by between 10–100% of the farmers, in study area are: Acrea sp, Aulacophora Africana, Helicoverpa armigera, Spodoptera litoralis, Zonocerus variegatus, Podagrica spp. and Acrea acerata. The infestation by these insects were not linked to specific morphotypes of C. olitorius, but varied by locality. The agricultural practices that might influence the presence of any C. olitorius pests were intercropping and dormancy cutting, seedling after sowing and number of harvests. This information will contribute to a better production of the varieties of C. olitorius and the different crop associations could be integrated into methods of ecological management of the pests of C. olitorius.

Background: Pigeonpea is a multipurpose food legume that contributes to food security in Benin. However, its production declined and some landraces are being threatened with disappearance. For establishment of conservation and breeding programs previous ethnobotanical surveys on pigeonpea were done in Benin but restricted to south and central regions. Knowing that pigeonpea is also grown in northern Benin, and that the varieties cultivated in this region can show agronomic performances, it is therefore important to evaluate the diversity of this legume in this region. However, an exhaustive documentation of pigeonpea diversity grown in Benin Republic are necessary for effective breeding and conservation programs. Therefore, this study aimed to document genetic diversity of pigeonpea, across the agro-ecological zones of Benin Republic for its promotion and valorization. Methods: 500 producers of pigeonpea belonging to thirteen sociolinguistic groups were selected through 50 villages. 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 Four Square Analysis method. A comparative analysis of pigeonpea uses categories, production systems, pigeonpea 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 colour and size. Seven pigeonpea use category were recorded including sacrifice, grain processing and fertilization. The results showed that pigeonpea seed system is informal. Based on seed characteristics, fifteen landraces were recorded with 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 threatened with disappearance was observed across the ecological zones. Ten constraints are known affecting pigeonpea production in Benin with pests and diseases as the most important in all agro-ecological zones. This study revealed that pigeonpea cultivation is increasing in the Sudanian zone. Varieties to be produced must be selected on the basis of 11 criteria among them precocity and resistance to pests and diseases, in the three ecological zones and adaptability to any type of soil in the Sudanian zone were the most important. The participatory evaluation revealed the existence of a few performing cultivars. Conclusions: Our results show that to implement a pigeonpea genetic conservation program in Benin, it would be necessary to take into account the diversity, production constraints and criteria of 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.

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. Keywords: Agriculture, Colocasia esculenta , constraints, farmers, preferences, production, Togo, Xanthosoma mafaffa

Bambara groundnut (Vigna subterranea (L.) Verdc.) is one of the important legume crop grown in marginal soils of sub-Saharan Africa. Despite its importance in food security and income generation for small scale farmers, it remains as a neglected and underutilized crop and the productivity is very low in the field due to the lack of improved varieties and lack adequate farming practices. Thus, the aim of this study is to investigate all aspects related to its production including source of seeds supply and farmers management practices, utilization, conservation and marketing. The results revealed that in this Region of Western Niger Bambara groundnut was mainly produced by female (95%) compared to male (5%). Farmers use their own recycled seed (80%) which is the main source followed by provision of recycled seeds by relatives (5%) and purchasing from the local market (15%). Also, this finding shows that there is a lack of adequate farming practices and the crop is mostly produced on inherited land without any inputs as reported by 80% of the respondents. Mono-cropping is mainly practiced by 97% of farmers while a few of them do rotation (2%) and most of pre and postharvest handling technologies are traditional. The most important traits preferred by Bambara farmers is seed colour (cream color), followed by high grain yield, early maturity and cooking ability according to the respondents with 98, 92, 88 and 72% respectively. Several features have to be taking into account in order to promote Bambara nut including its ability to do well in harsh conditions, its nutritional benefits, and its ability to fix nitrogen, thereby increasing soil fertility in mixed cropping systems.

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.

Taro and yautia are two edible aroids grown in the humid tropics of Asia, Africa and Latin America and used as staple food crops by millions of people in developing countries. They are mainly propagated vegetatively. Selection and improvement of these crops require characterization using desirable morphological traits for various end-uses. An agro morphological characterization study was conducted at the experimental site of Centre de Recherche Agronomique du Littoral (CRAL) of Institut Togolais de Recherche Agronomique (ITRA) in Togo. The aim of the study was to evaluate the morphological variation within taro and yautia accessions. A total of 127 accessions (26 accessions of taro and 101 accessions of yautia) were grown in a randomized complete block design with three replications from October 2016 to November 2017. Thirty-eight (38) characters were studied for taro and twenty-eight (28) for yautia. Data was analyzed using ANOVA, factorial and clustering analyses. Findings of ANOVA show high positive correlations between vegetative traits such as plant height, plant span with corm and cormels weight. The factorial analysis and dendrogram of the HCA, based on the agro morphological traits, showed four major groups for taro accessions and three groups for yautia accessions. The results demonstrated morphological variation among taro and yautia grown in Togo. Findings from this study are an important data base for conservation and use of these crops in Togo. However, the results suggest also the existence of duplicate in the collection. Ploidy analysis and molecular studies are required to complement and confirm the current agro morphological variation. Key words: Colocasia, Xanthosoma, Araceae, morphology, diversity, Togo.

The main goal of this study is to gain insight into the relationship between the genetic profile of cultivated rice (Oryza spp.) accessions and their resistance to rice blast. Therefore, the genetic and phenotypic variability of a set of 350 cultivated rice accessions originating from Africa (Benin, Mali and Nigeria, Ivory Coast etc.) was examined. Seventy-seven fluorescent amplified fragment polymorphism (AFLP) markers were used to gain insight into the genetic variation and to classify the germplasm collection. In addition, the rice germplasm was assessed for its resistance to blast disease caused by Pyricularia oryzae in upland field conditions. Huge differences in responses of rice accessions to P. oryzae were observed, ranging from highly susceptible to highly resistant. Twelve percent of all accessions were highly resistant to P. oryzae. Based on their AFLP marker profile these highly resistant accessions could be separated from the other accessions. Stepwise regression revealed that the best prediction of the blast resistance level was achieved with a maximum number of 13 AFLP markers. Marker CTA22 was the most important for accurate prediction of blast resistance, this marker was present in all highly resistant accessions. It can be concluded that AFLP markers are a valuable tool to screen rice accessions for their susceptibility towards blast disease and that, based on a subset of markers, it is possible to predict the resistance to rice blast.

Bambara groundnut (Vigna subterranea (L.) Verdc.) is a neglected and less exploited species in Benin. However, the rational use of the different landraces available involves an appropriate knowledge of their characteristics. This study examined the characteristics of 52 local landraces of Bambara groundnut traditionally cultivated in Benin based on 12 qualitative and 11 quantitative variables, in order to expose those of good qualities. After a classification based on the morphological variables of the seeds, the experimental field was installed in a completely randomized device of blocks repeated three times. The collected data was analyzed with Statistica 7.1 and NTSYS PC 2.2. softwares using qualitative characteristics (Growth’s type, Stem’s hairiness, Flower’s colour, Leave’s shape etc.). As result, the number of morphotypes increased from 18 (out of classification) to 47. Therefore, it appears that the Benin collection of Bambara groundnut is broad in morphological variability. The analysis of the principal component of the quantitative variables revealed three specific classes within the collection. The most efficient variety which belonged to the second class, had a high field yield per hectare (> 1 t/ha). The Souhouloumankpa variety yielded the earliest (103 days after sowing) in addition to the high field yield. The study also showed a positive relationship between 100 seed’s weight, their length, the number of seeds per plant and the seed’s field yield in kg/ha. For a sustainable preservation and an improvement of the available resources, a molecular characterization of the Bambara groundnut landraces in Benin Republic needs to be done.

A series of β -ionone-derived curcumin analogs (1a – 1j) have been synthesized by condensation of β -ionone with a variety of aldehydes. The synthesized compounds were screened for their in vitro anti-inflammatory activity against lipopolysaccharide (LPS)-induced expression of the pro-inflammatory cytokines tumor necrosis factor- α (TNF- α) and interleukin-6 (IL-6). Five active compounds exhibited dose-dependent inhibition of the release of TNF-α and IL-6. The active analogs represent a new class of anti-inflammatory agents with improved potency as compared to curcumin. Furthermore, the active compound 1e showed a protective effect against LPS-induced septic mortality in vivo. Our results suggest that the obtained analogs may be further developed as potential agents for the prevention and treatment of inflammatory diseases.

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.

Cassava (Manihot esculenta Crantz) is one of the highly produced and consumed food crops in Benin Republic. Through the application of participatory research appraisal tools and techniques, such as direct observations, group discussions and field visit, cassava production constraints, the diversity at the community level and farmers’ varieties preference criteria were assessed in southern Benin. Base on national statistic cassava production fifty five (55) villages were selected and surveyed in the southern Benin. Descriptive statistics were used to analyse the data collected. About 11 constraints were listed by farmers, and the most important were low productivity, low post-maturity underground storage capacity of the roots of some cultivars, viral disease (cassava mosaic disease), susceptibility to high soil moisture, and lack of early maturing cultivars, which together accounted for 68.02 % of the total responses. Additionally, a total of 125 existing landraces were recorded. The distribution and extent pattern revealed 59 elites cultivars (cultivated by many households and on large areas) that were further grouped into 23 categories based on their agronomic, technological and culinary characteristics. In most of the villages, the farmers’ perception of cultivar loss was based on abandonment of some cultivars due to their poor agronomic (69.12 % of responses) and culinary and/or technological attributes (30.88 % of responses). Within the existing diversity, cultivar choice or preferences are based on 22 culinary, technological, agronomic and economic criteria and their importance vary across the different department. Among these criteria, the most important were high productivity, good quality of the gari, early maturity and good friability accounted together for 48.12 % of the total responses. The presence of duplicates or synonyms was also observed and it is suggested that both morphological and molecular characterization and classification be carried out for better identification of cultivars.

Variability study of agro-morphological characteristics is important for varietal improvement and plant breeding program. For this, 148 chili pepper landraces (Capsicum annuum L.) collected from Northern Benin were characterized using 39 (21 qualitative and 18 quantitative) morphological characters. The trial was conducted in a Fisher block design with 3 replicates at the experimental station of the Faculty of Science and Technology (FAST) of Dassa based in Central Benin. The results revealed considerable morphological variability between landraces. Twenty nine (16 quantitative and 13 qualitative) variables among the 39 examined were discriminatory and group the landraces into 4 classes when considering the qualitative variables. With quantitative variables, 9 groups were obtained. The correlations between the studied quantitative variables show that the yield parameters are correlated with the variables related to the vegetative part of the plant. This study will help breeders to better select their parents for crossing in order to produce desirable and high yielding varieties.