Agro-ecological Zones Of Benin Research Articles

Finding optimum climatic parameters for high tomato yield in Benin (West Africa) using frequent pattern growth algorithm.

Tomato is one of the most appreciated vegetables in the world. Predicting its yield and optimizing its culture is important for global food security. This paper addresses the challenge of finding optimum climatic values for a high tomato yield. The Frequent Pattern Growth (FPG) algorithm was considered to establish the associations between six climate variables: minimum and maximum temperatures, maximum humidity, sunshine (Sun), rainfall, and evapotranspiration (ET), collected over 26 years in the three agro-ecological Zones of Benin. Monthly climate data were aggregated with yield data over the same period. After aggregation, the data were transformed into 'low', 'medium', and 'high' attributes using the threshold values defined. Then, the rules were generated using the minimum support set to 0.2 and the confidence to 0.8. Only the rules with the consequence 'high yield' were screened. The best yield patterns were observed in the Guinean Zone, followed by the Sudanian. The results indicated that high tomato yield was associated with low ET in all areas considered. Minimum and maximum temperatures, maximum humidity, and Sun were medium in every Zone. Moreover, rainfall was high in the Sudanian Zone, unlike the other regions where it remained medium. These results are useful in assessing climate variability's impact on tomato production. Thus, they can help farmers make informed decisions on cultivation practices to optimize production in a changing environment. In addition, the findings of this study can be considered in other regions and adapted to other crops.

Farmers’ Perception of Viral Diseases and Their Management in Pepper (Capsicum spp.) Production in Benin

Pepper (Capsicum spp.) is an important solanaceous cash crop in Benin; however, productivity is limited due to several key constraints, especially diseases caused by viruses. We sought to understand farmers’ perceptions of viral diseases, management strategies deployed, and to identify the virus population affecting pepper production in Benin. To assess farmers’ perceptions and management of viral diseases, a survey was carried out in four agroecological zones of Benin. A total of 144 pepper farmers were interviewed using the snowball method. A total of 52 pepper leaf samples with virus-like symptoms were collected and diagnosed by reverse-transcriptase polymerase chain reaction (RT-PCR) or PCR. Pepper production systems varied across agroecological zones (P ≤ 0.001) with a predominance of farms practicing monoculture (82%). The majority of farmers (89%) indicated that pests and diseases were the main constraints to increased production. Cucumber mosaic virus (92% of the total samples), Pepper vein yellow virus (52%), and Pepper veinal mottle virus (50%) were the major viruses detected in pepper fields in Benin. There were both single (29%) and mixed (71%) infections of the viruses, suggesting that mixed infections are common for pepper in Benin, confounding efforts to reduce virus infections. Nearly 100% of the farmers surveyed were not aware of these viral diseases. They also could not directly relate symptoms of virus infection to the presence of aphids, whiteflies, or thrips. Farmers relied primarily on synthetic insecticides (93%) to control virus vectors. Interestingly, some farmers applied commercial (12%) and homemade (17%) biopesticides, with neem-based preparations being the most widely used. A total of 15% of farmers used companion cropping with maize, mint or basil and 43% of farmers used crop rotation as a cultural management practice to control viral disease and vector pressure in pepper fields. The implications of this work include the importance of training farmers and extension agents on diagnosis of viruses and their vectors causing viral diseases. This study provides baseline information for the development of host-resistant cultivars and deployment of integrated pest management strategies for pepper in Benin to reduce farmer losses.

Heterogeneity of preferences and breeders’ willingness to pay for improved livestock system in Benin, West Africa

The productivity of livestock, including small ruminants, in Benin, is very low, and their management practices in terms of feeding, health and reproduction do not ensure their optimal production. This research aimed to assess the willingness of sheep and goat keepers to pay for an improved breeding system. Data collection from 118 sheep and 375 goat breeders selected in six agroecological zones of Benin was undertaken using the choice experiments. The mixed logit model revealed heterogeneity in the preferences of small ruminant keepers for breeds, feeding practices, health treatments and reproductive control. This heterogeneity of preferences was confirmed by the latent class logit model results, which revealed the existence of four classes of sheep breeders and three classes of goat breeders. Irrespective of species, small ruminant breeders were generally willing to use herbal medicine or combine it with modern veterinary medicine and adopt Sahelian breeds or crossbreeds (Sahelian x Djallonke). They were not willing to adapt neither zero grazing nor controlled reproduction. The combination of the coefficient estimates of the latent class logit model and the determinants of class membership showed that herders in southern Benin with small and monospecific herds were the most willing to introduce changes in their breeding system.

Hill-placement of manure and fertilizer for improving maize nutrient- and water-use efficiencies in the northern Benin

Optimizing the use of organic and mineral fertilizer in rain-fed maize production is crucial for sustainable food production in sub-Saharan Africa. This study investigates the effect of hill-placement of two nutrient sources (farmyard manure and synthetic fertilizer) on nutrient- and water-use efficiencies of maize crops i.e. recovery efficiency (NUEre), internal utilization efficiency (NUEie) and water use efficiency (WUE). A four-year trial was conducted in the tropical sub-humid zone of the northern Benin with a factorial combination of farmyard manure at three levels (0, 3 and 6 t ha−1, hereafter NM, 3M and 6M, respectively) and three levels of fertilizer [0% (NF), 50% (50F) and 100% (100F) of the recommended rate (76 kg N + 13.1 kg P + 24.9 kg K ha−1) by the national center for agricultural research. The NUEre decreased with increasing rate of manure and/or fertilizer, but the decreasing rate was lower under combined manure and fertilizer application. However, the NUEie increased with the increasing manure and fertilizer amounts. The WUE was significantly higher in 3M and 6M treatments than in NM treatment, and higher in 50F and in 100F than in NF treatments. The combination of 3000 kg ha−1 farmyard manure with half recommended fertilizer rate (100 kg ha−1) could be suggested as an optimal nutrient management practice for maize production in the Northern Benin. Future studies should target the other agro-ecological zones in Benin, and also consider other widely cultivated crops in the study area for reducing yield gaps and promote food security.

Socio-demographic factors and ethnobotanical knowledge associated with sesame management practices across agroecological zones in Benin

Summary Sesame is an oilseed crop and source of income for small-scale farmers, particularly in developing countries. In Benin, sesame production is poorly developed and the underlying reasons are still unknown. In this study, we investigated the sesame management practices, socio-demographic factors and ethnobotanical knowledge associated with sesame production, as well as the production constraints across four agroecological zones in Benin. In total, 370 farmers were surveyed based on a structured interview. Qualitative and quantitative data including socio-demographic parameters, management practices and knowledge associated with the crop, were recorded. A binary logistic regression was performed to explain the effects of socio-demographic parameters on management practices. The farm typology was generated through a principal component analysis followed by a cluster analysis. Cultivars were classified based on the seed coat colour and size. To assess the ethnobotanical knowledge related to sesame, use value, plant part used value and fidelity level were calculated. Our results showed that older farmers were more likely to practice intercropping than young farmers. In addition, male farmers applied more fertilisers and used more pesticide than female. Five distinct farm typologies were recorded in the four agroecological zones. Five different cultivars were recorded across the four agroecological zones. Sesame is mostly produced for local consumption as sauce and seed appetiser (mentioned by at least 73.23% of respondents). The seeds were the most used part of the crop. The lack of improved seeds, road impassability to the field, rarity of rain, non-availability of cultivable land for sesame production, lack of cash for farm operations were the main constraints to wide sesame production. We discussed the differences among farm typology and their productivity and proposed future research actions for expanding sesame production in Benin.

Effect of bird scaring methods on crop productivity and avian diversity conservation in agroecosystems of Benin

Farmers are developing methods to scare off and reduce bird damages. The aim of this study is to explore the effect of these methods through a simple form of evaluation that allowed to highlight relationship between these methods and productivity on the one hand, and the relationship between these methods and conservation of birds in the agricultural environment according to different vegetative stages on the other hand. 713 farmers were interviewed in the agro-ecological zones of Benin. This study reveals the use of four methods. These are auditory method, visual method, exclusion method and mixed method. They are used primarily to reduce "loss and damage" and "reduce the frequency of bird visits". 96.78% of farmers agreed that these methods improve yields. Moreover, effectiveness of the methods varies according to the vegetative stages and the duration of its application. Bird species richness was also significantly and positively influenced by bird control methods (Maize: p= 5767e-3) and (Rice: p=4482e-6). Long-term studies, generalized to different forms of agricultural area, are needed for a better assessment.

Organic Fertilizer Based on Rhizophagus intraradices: Valorization in a Farming Environment for Maize in the South, Center and North of Benin

Maize plays an important role in agricultural production systems in all agro-ecological zones of Benin. Despite its importance, its production faces many constraints including soil fertility. One of the ecological technologies aimed at improving agricultural production is the use of soil microorganisms including arbuscular mycorrhizal fungi (AMF). This study aims to evaluate the effectiveness of Rhizophagus intraradices, an indigenous strain, on maize productivity in farmers' areas in the Research and Development (RD) sites of the North (Ouénou), Center (Miniffi), and South (Zouzouvou). Three maize producers were selected at each RD site, for nine maize producers. The experimental design was a randomized complete block of three treatments with three replications. The different treatments were (i) Control–farmer's practice, (ii) R. intraradices + 50% of the recommended dose of NPK and urea, and (iii) 100% of the recommended dose of NPK and urea. Soil samples from the different RD sites were taken at a depth of 0–20 cm before sowing for chemical analysis. The different growth parameters (height, crown diameter, and leaf area), grain yield, and endomycorrhizal infection of maize plants were evaluated. The results showed that the soils were moderately acidic (5.5 ≤ pH waters ≤ 6.8) and low in organic matter (0.95 ≤ 33 OM ≤ 1.17) regardless of the study area. The greater maize grain yield was recorded with application of 100% of the recommended dose of NPK and urea, and R. intraradices + 50% of the recommended dose of NPK and urea. In the RD sites at the South, Center, and North recorded with R. intraradices + 50% of recommended dose of NPK and urea, the grain yields of 1.9, 3.4, and 1.74 t/ha with an increase of 28, 38.21, and 13.21%, respectively, compared with farmer's practice. Mycorrhization frequencies in plants treated with Ri¹ N15P15K15 vary between 37.44 and 51.67% in the three zones. The results of the current study have proven the potential use of R. intraradices in sustainable intensification of maize production in Benin.

Socioeconomic and Cultural Importance of The Yellow-Fronted Canary (Serinus Mozambicus) in Northern Benin

The species yellow-fronted canary undergoes a real traffic due to its song and medico-magical properties in order to supply local commercial networks. This study aims to assess the socioeconomic and cultural importance of this bird in order to identify the cohorts of actors involved along this activity chain. In this context a survey was carried out among 400 breeders in four agroecological zones of Benin (ZAE II; ZAE III, ZAE IV and ZAE V). The questionnaire also focused on general characteristics of the respondents on aspects related to general knowledge of the bird, its social importance, purchase and sale price, cultural importance and breeders’ perceptions. Canary traders, mostly with primary education level (63.25%) and Muslim (97.5%), were on average 44 years old and an average experience of 27 years. They exercised this activity in part-time (96.5%). The knowledge about canary is shared is different depending on the ethnic group. The activity was profitable for all of them (100%) with 128,624 FCFA (233.18 USD) net profit per month. The trader's education level, whether or not he belonged to ZAE II, the number of birds he had in his possession, the daily amount he invested in their food, their selling price, the number of years he made the activity, his experience in the business were the factors that determine the net profit of the canary’s trader. However, canaries' breeding in north-Benin is based on a complex system with actors who develop many myths around medico-magical practices. This study was necessary to better assess the pressure on the species in order to anticipate its conservation.

Farmers’ and Herders’ Perceptions on Rangeland Management in Two Agroecological Zones of Benin

The sustainable use of rangelands in pastoral areas requires the inclusion of all stakeholders to develop sound management strategies. However, the role of these actors in the sustainable management of natural resources is still poorly understood. The present study aims to (i) assess the perception of farmers and herders of the risks and opportunities of transhumance on rangeland resource use and management, and to (ii) generate useful knowledge for the design and implementation of policies that favor the coexistence of these actors and reduce competition over rangeland resources use in Benin. To this end, interviews were conducted with 240 crop farmers and herders using a semi-structured questionnaire in two contrasting agroecological zones in the northern (Kandi) and the southern (Kétou) part of the country. Among the respondents, 64% of farmers in the North were agro-pastoralists (owning 10.6 ha of land and 10.7 cattle) and 36% were herders (keeping 45.8 cattle and cultivating about 3.7 ha of land). They perceived that communal rangelands were entirely degraded. In the South, 36% of respondents were agro-pastoralists (with 0.3 cattle and farming 4 ha of land) and 64% cattle herders (raising 45.3 cattle and farming 0.9 ha of land only). Of the herders, 50% kept cattle for more than 20 years, while agro-pastoralists had no previous experience in cattle herding. Cultivation practices among crop farmers, such as high use of mineral fertilization (23.8%) and bush fires for land clearing (22.5%), were reported in Kandi (North) and Kétou (South) as factors that might contribute to land degradation. However, these farmers perceived transhumance as a threat to the sustainable use of natural resources. In contrast, herders perceived transhumance as an opportunity to valorize unused land and increase the availability of manure to cropland. The prevalent negative attitude of crop farmers regarding transhumant herders increases the vulnerability of cattle herding in both regions. There is an urgent need of raising awareness concerning the mutual benefits provided by the coexistence of crop farmers with herders to promote participative rangeland management strategies. This may contribute towards coping with the current challenges of food insecurity and increasing climate variability as well as to reducing recurrent conflicts in the region.

Adaptation of plants derived from cultivated yam of Dioscorea cayenensis–D. rotundata complex species seeds germination in two agroecological zones of Benin

Vegetative propagation of plants promotes the accumulation of viruses in plant material; this causes the loss of vigor and consequently the drop of vegetable yield. Keep up productivity level of vegetatively propagated plants; it is therefore important to regenerate genetic material by sexual reproduction to improve the biodiversity. The main objective of this study is to improve yam seeds by sexual way, specifically to assess the response of seedlings from yam seeds in two agroecological areas, area IV (Djougou), in Sudanese climate and area V (Bantè), in transition climate. Seedling were transplanted in this agroecological areas using a completely Randomized design with three replications. Data was analyzed using one way ANOVA at 5% level of significance and a mean comparison test. Seedling survival rate is significantly different, 55.41% in zone IV and 23.60% in zone V, but the rate of tuberization of the two areas is similar, 55.63%; of zone IV and 57.62%; of zone V. The average of the tubers length and their weight are respectively 13.21 cm and 24.87 ± 19.22 g in zone IV and 8.95 cm and 10.30 ± 9.91 g in zone V. This results show that microtubers produced from the seeds show a high degree of heterogeneity, and, varieties creation and improvement is possible from the seeds. This technique would promote the selection of varieties adapted to current climatic conditions.

Adaptation of plants derived from cultivated yam of Dioscorea cayenensis–D. rotundata complex species seeds germination in two agroecological zones of Benin

Adaptation of plants derived from cultivated yam of Dioscorea cayenensis–D. rotundata complex species seeds germination in two agroecological zones of Benin

Addressing gendered varietal and trait preferences in West African maize

Maize is the most important cereal in Sub Saharan Africa; however, yields are significantly lower than those possible with improvements in cultivars and management. Maize breeding programs need to produce material with improved resistance to increasing environmental stresses and incorporate the man and women farmer preferred traits that relate to yield, postharvest, nutritional, and processing qualities. This research uses gender-disaggregated data recorded during participatory on-farm maize trials by the Stress Tolerant Maize Program conducted in agroecological zones of Benin, Nigeria and Mali) to identify men and women farmer’s expressed varietal and trait preferences in order to evaluate plant breeding strategy. A multi-stage varietal and trait identification process was used to identify gender shared and distinctive varietal trait preferences for product development and dissemination. The data indicates that progress has been made by the Project in considering the range of traits valued by both men and women farmers and indicates those that should be considered for gender-focused product pipeline development in the future. The study concludes by underlining the need for adjustment in breeding to improve partnerships with food scientists, postharvest specialists and private seed sector on the packaging and delivery of technologies to farmers and other value chain actors.

Modelling current agro-ecological zones for the cultivation of Dioscorea dumetorum (Kunth) Pax, a neglected and underutilized yam species in Benin (West Africa)

Yam species (Dioscorea spp.) constitute important staple foods for local communities in Sub-Saharan in Africa. Among yam species, Dioscorea dumetorum (Kunth) Pax, commonly consumed, has been reported to be among the most nutritious and well-appreciated local resource although it remains neglected and underutilized species in Benin. Here, we combined occurrence records and environmental data (bioclimatic and soil data) in ecological niche models to assess the suitable areas for the two locally acknowledged varieties of the species: the cultivated and the wild varieties. Results showed that the potential cultivable area of the cultivated variety is twofold, the one of the wild variety. Seven and five of the eight agro-ecological zones of Benin are potentially suitable for the cultivation of the cultivated variety and the wild variety, respectively. Differences in the two varieties of ranges could result from the adaptation of each variety to local conditions reinforced by intrinsic characteristics of each variety. These results constitute an important step towards scaling up the species valorization while developing conservation programs for both varieties. Further genetic investigation and field experiments could shed light on the origin of the differences between these two forms.

Inoculation of <i>Rhizobiums sp</i> Strains to Improve Soil Fertility: A Peanut Trial in Covè and Ouessè (Benin)

Thought the increasing demand Arachis hypogaea L. (groundnut), its yields remain low with increasingly using chemical fertilizers. To reduce the costs for chemical fertilizers inquisition and their long-term toxic effects on soils, microbial bio-fertilizers could be an accessible alternative to peanut farms. Thus, the aim of this study was to assess the performance of rhizobia strains on peanut varieties production. The experiments were conducted in two agro-ecological zones of Benin, in a peasant environment peasant-researcher control or under peasant and researcher control. The experimental device used was a complete random block with nine repetitions and two factors namely inoculation (with Rhizobium sp and without Rhizobium sp) and mineral fertilizer (with N15P15K15 and without N15P15K15). The effects of these factors divided into four treatments were evaluated on the plants vegetative, symbiotic and production parameters. In addition, an evaluation of each treatments’ comparative advantages was carried out. The results showed that the association Rhizobium sp and N15P15K15 induced groundnut plants best vegetative and productive parameters. The best comparative advantages in economic terms were also recorded with the same combination (Rhizobium sp + N15P15K15). Considering the technical performance, the recorded treatments effects can be classified as follows: Control Rhizobium sp 15P15K15 Rhizobium sp + N15P15K15. Thus, the association Rhizobium sp + N15P15K15 induced both the best plants vegetative and productive parameters and the best comparative advantage from an economic point of view. The results also showed that the plants’ response to inoculation, the application of manure and their combination was more marked in the bar soil zone (Covè) than in the cotton zone (Ouessè). Considering the negative effects linked to the use of chemical fertilizers, the use of Rhizobium sp could be an interesting path to increase the groundnut production.

Soil Fertility Level and Cropping Practices Determining Soybean Yield in Northern East and Center of Benin

Soybean is a food security crop in Benin due to its high nutritional value but its yield in the farmers’ cropping system is very low. The present study aims to provide appropriate response to the yield variability among fields in two agro-ecological zones of Benin namely: Southern Borgou zone (AEZ 3 in the north) and cotton zone of central Benin (AEZ 5). Soil samples were collected from 0-20 cm depth in 120 fields (50 in the AEZ 3 and 70 in the AEZ 5). pH (water), soil organic carbon (Walkley and Black method), total nitrogen (Kjeldahl method), CEC (0.01 N ammonium acetate at pH 7 method) and available phosphorus (Bray 1) were determined in the laboratory of Soil Science Water and Environment (LSSEE) of the National Agricultural Research Institute of Benin (INRAB). Cropping system (crop rotations, soil fertility management practices) were also collected using an open ended questionnaire. Classification and regression trees (CARTs) models were used for data analyses. Soybean yield variability among the agro-ecological zones were registered and the highest yield recorded was less than 1 t.ha-1. Considering soil characteristics, soil organic matter level was the most important variable determining yield variability. Furthermore, quantities of P applied and farmyard manure were cropping practices inducing yield variability (86.4% and 15% of the variability respectively). Our results also show that, yield differences noticed among the agro-ecological zones were induced by CEC and pH (water). The study suggested promotion of integrated soil fertility management practices to sustain soybean yield in the study area.

Local agro-ecological condition-based food resources to promote infant food security: a case study from Benin

Children are still undernourished in many developing countries. A way to address this issue is to make better use of local food resources. The present study documents local plant and animal resources used for feeding infants and young children across the agro-ecological zones (AEZ) of Benin, with a focus on the availability of resources and consumption forms. It describes similarities and differences among the AEZs and identifies proposals for infant food formulations at the AEZ level. A literature review was performed and supplemented with a survey in 42 villages of eight AEZs of Benin. The selection of municipalities was based on the prevalence of food insecurity. In total 969 people were interviewed through focus group discussions and individual interviews using pre-established interview checklists and questionnaires. Data were processed with statistical tools, including non-metric dimensional scaling analyses, descriptive statistics and Chi2 test of independence. Results showed disparities in the distribution and use of local food resources for infant foods in the AEZs. AEZ 1 represented by Karimama and AEZ 2 represented by Banikoara (both in the Sudanian zone, with about 900 mm rainfall per year in one long rainy season and one long dry season) had the lowest diversity of local food resources used in children’s feeding, while AEZ 5 represented by Aplahoue and Ouesse (both in the Guinean zone, with about 1200 mm rainfall per year over two rainy seasons and two dry seasons), and AEZ 8 represented by Adjohoun and Bopa (both in the Guinean zone with about 1200 mm rain per year) had the highest diversity. The baobab tree (Adansonia digitata) and groundnut (Arachis hypogea) were the plant resources recording the highest number of usages for food in general and infant foods in particular. High similarities in the species used for infant food existed among AEZs 5, 6, 7 and 8 whereas AEZ 1 and AEZ 4 had no match with resources used for infants in the other AEZs, mainly due to food cultures and availability. These findings indicate the usefulness and efficiency of an approach to formulate generic infant food formulas based on grouping AEZs with similar resources. Further studies are needed to assess the quantitative availability of local food resources throughout the year, the links between food prices and purchasing power of the population, and to assess the bioavailability of nutrients in infant foods made from local food resources in relation to food preparation methods.

The role of abiotic factors on both mango infestation and Sternochetus mangiferae abundances in mango agroecosystems in Benin

AbstractTo develop management strategies for the mango seed weevil (Sternochetus mangiferae), we surveyed infestation levels of the pest in three agroecological zones of Benin and determined the influences of abiotic factors on mango infestation levels and population dynamics in mango orchards at IITA-Benin from 2009 to 2011. We collected immature and mature fruits from the canopy and fallen fruits from under the canopy from three randomly selected trees per cultivar, per orchard. Samples were examined to determine the number of the mango seed weevil eggs to adults during the rainy seasons of three years of the study. Our results show that the highest abundance of both the weevil and its eggs was from March to May of each year. In the first year of sampling, the cultivar Eldon was more infested than the other two cultivars, while during the second and third years, the cultivar Alphonse was most infested. The occurrence of the weevil was almost nil in the hot agroecological zones, while for the mango cultivars of IITA-Benin the percentage of infested fruit increased or decreased according to the studied variables, such as temperature, rainfall, and relative humidity. We found that the period from March to May with low temperatures and high rainfall was favourable to the population increase of mango seed weevils. We discuss possible implications of our findings for the management of the pest.

Assessment of the physical and mechanical properties of the soils in the different agroecological zones of Benin

The physical properties of soils are important for proper monitoring of soil functions. In order to evaluate soil resistance to agricultural equipment, a study was carried out on the four main soil types (ferralitic, ferruginous, hydromorphic and vertisol) in the eight agroecological zones of Benin. The objective of this work was to determine the physical and mechanical parameters of the soils. A sampling of soil types by agroecological zone was carried out in 36 localities in Benin to record vertical and horizontal soil strengths using a compactometer and a penetrometer. These data were complemented by measurements of texture, density and water content of the soil samples. Ananalysis of variance, polynomial regressions and Pearson correlation were performed between the parameters studied. It is noted that majority of soils assessed were sandy loam. The high sand content in most soils would be due to the depth considered (20 cm). The bulk densities range from 1.21 to 1.73gcm-3 and water contents from 4.9 to 35.11%. Vertical resistances range from 3.89 to 16.36 kg cm-2 and horizontal resistances from 1.03 to 4.44 kg cm-2. Strong soil resistances (vertical and horizontal) are recorded in the northern part of Benin where large proportions of the gravelswere observed in the samples taken. A positive correlation was observed between vertical resistance and horizontal soil resistance. It can be concluded that soil resistance in Benin vary from one agro-ecological zone to another, but the linking of soil properties is less significant between zones.Keywords: Soil compaction, soil resistance, penetrometer, agroecological zones, Benin

Survey of farmers\u2019 knowledge of cassava mosaic disease and their preferences for cassava cultivars in three agro-ecological zones in Benin

BackgroundCassava is an important crop in Africa that is widely cultivated for its starchy tuberous root, which constitutes a major source of dietary carbohydrates. Cassava mosaic disease (CMD) is the most devastating disease affecting cassava in Africa and causes enormous losses in yield. In Benin, specifically, cultivars resistant to CMD are not commonly planted, and even when CMD is observed in fields, farmers do not implement control measures, presumably because they lack proper knowledge and training. Our study aimed to evaluate farmers’ knowledge of CMD to determine whether there is consistency between farmers’ criteria for selecting cassava cultivars and the currently CMD-recommended cassava varieties.MethodsWe conducted structured interviews with 369 farmers in 20% of townships in each of three agro-ecological zones in Benin between November 2015 and February 2016. Farmers were selected randomly in each household, and their fields were assessed for CMD incidence and severity.ResultsAll farmers surveyed, representing a broad demographic pool with regard to education level, age group, and years of experience in cassava production, successfully recognized CMD symptoms in photos, but most (98.60%) said they did not know the causes and vectors of the disease. Most farmers (93.51%) reported that they obtain planting material from neighboring fields or their own fields. In total, 52 unique cultivars were identified, of which 3 (5.76%) were preferred based on their yield and precocity and 3 (5.76%) were preferred based on taste or ability for transformation. The assessment of disease incidence and severity showed that the areas most affected by CMD were Comè Township (37.77% of fields affected) and agro-ecological zone VIII (26.33%).ConclusionFarmers already know how to recognize the symptoms of CMD and could implement control measures against it if they are trained by researchers. Across all surveyed areas, we identified six preferred cultivars based on the four most commonly stated preference criteria (precocity, yield, gari, and taste. Our results suggest that farmers will be more likely to use CMD-resistant cultivars and clean plant material if the plants meet their existing preference criteria. We suggest that CMD-resistant cultivars will be embraced only if the recommended cultivars are strategically aligned with the characteristics desirable to the cassava farmers in each region.

Ecological sustainability and environmental risks of agricultural intensification in inland valleys in Benin

To meet food demand after the failure of irrigation system developments, agricultural intensification is occurring in inland valley agro-ecosystems in sub-Saharan Africa. Agricultural enhancement in inland valleys, which undermines environmental sustainability, was assessed using ‘Driving Force–Pressure–State–Impact–Response’ approach in four agro-ecological zones of Benin. The survey revealed that inland valleys are largely devoid of ligneous species. Crop residues are mainly transferred from inland valley fields to feed cattle, burnt in situ by the farmers themselves or abandoned to wildfires or to pasture—not mulched. Crop diversification is not universal and is limited to rice and vegetables crops. Monocropping of rice, practised by 83.3% of inland valley farmers, requires large chemical fertilizer application despite their impacts on environment including land degradation and water contamination. A major challenge is to determine means of characterizing entire agro-ecosystems of inland valleys in a way that is simple enough to be effectively and efficiently monitored. Inland valley agricultural development projects might include backstopping activities and policies that enable monitoring of chemical inputs and farming practices in inland valleys to reduce negative impacts on the environment and human health.