Developing improvement strategies for management of the Sisrè berry plant [Synsepalum dulcificum (Schumach & Thonn.) Daniell] based on end-users’ preferences in Southern Nigeria

Synsepalum dulcificum is a valuable horticultural and lesser-known crop, famous for the uniqueness of its taste modifying properties, which is candidate for genetic improvement in West Africa. Semi-structured interviews were conducted with 100 respondents purposively selected to analyze the current production systems and constraints as well as to document the farmers’ and consumers’ preferences for breeding traits in Southern Nigeria. The results showed that none of the investigated farmers applied all required crop management practices to produce the species (land cleaning before establishment, pegging and lining, holing, base manure application, crop irrigation, weeding, pruning, fertilizers application, and pests and diseases control). Farmers were grouped into three clusters based on crop management practices. There was a strong and highly significant agreement among farmers (Kendall’s W = 0.8, p < 0.001) that bush fire, poor plant growth, drought, pests, and parasitic weed were the five most important constraints in Southwest Nigeria. In Southeast Nigeria, damage by insects and birds, poor seed germinability and poor knowledge of cultivation technics were the most important constraints challenging production. Farmers’ agreement around these constraints was moderate but highly significant (Kendall’s W = 0.6, p < 0.001). Overall, the top three desired breeding traits by farmers included: high growth rate, extended fruit shelf-life, and high fruits yield while the top three consumer’s preferences included: high miraculin potency (long lasting action of the miraculin), fruit glossiness, and high metabolites content. However, cultural specificities were detected in these preferences with a higher agreement in Yoruba farmers’ preferences compared with their counterparts Igbo. The Igbo consumers showed a higher concordance in their traits’ preferences than the Yoruba consumers. These findings pave the way for an informed cultivar development for the Sisrè berry plant in Nigeria and expand knowledge on end-users’ preferences for the species in West Africa

Comparative analysis of management practices and end-users' desired breeding traits in the miracle plant [Synsepalum dulcificum (Schumach & Thonn.) Daniell] across ecological zones and sociolinguistic groups in West Africa

Background: Understanding end-users' preferred breeding traits and plant management practices is fundamental in defining sound breeding objectives and implementing a successful plant improvement programme. Since such knowledge is lacking for Synsepalum dulcificum, a worldwide promising orphan fruit tree species, we assessed the interrelationships among socio-demography, ecology, management practices, diversity and ranking of desired breeding traits by end-users of the species (farmers, final consumers and processing companies) in West Africa. Methods: Semi-structured interviews, field-visits and focus groups were combined to interview a total of 300 farmers and final consumers belonging to six sociolinguistic groups sampled from three ecological zones of Benin and Ghana. One processing company in Ghana was also involved. Data collected included socio-demographic characteristics; crop management systems and practices; and preferences of farmers, final consumers and processing companies and ranking of breeding traits. Data were analysed using descriptive statistics, independence, and non-parametric tests, generalized linear models, multi-group similarity index and Kendall's concordance coefficient. Results: Men (86.33% of respondents) were the main holders of S. dulcificum in the study area. The three most frequent management practices observed in the species included weeding, fertilization and pruning, which were applied by 75.66%, 27.33% and 16.66% of respondents, respectively. The management intensity index varied significantly across ecological zones, sociolinguistic groups, and instruction level (p 0.05). General multigroup similarity indices (CTS ) for farmer-desired traits, on one hand, and final consumer-desired traits, on the other hand, were high across ecological zones (CTS ≥ 0.84) and sociolinguistic groups (CTS > 0.83). Nevertheless, respondents from the Guineo-Congolian (Benin) and the Deciduous forest (Ghana) zones expressed higher agreement in the ranking of desired breeding traits. Preference for breeding traits was 60% similar among farmers, final consumers, and processors. The key breeding traits desired by these end-users included in descending order of importance big fruit size, early fruiting, high fruit yielding (for farmers); big fruit size, high fruit miraculin content, fruit freshness (for final consumers); and high fruit miraculin content, big fruit size, high fruit edible ratio (for processing companies). Conclusion: This study revealed stronger variations in current management practices across ecological zones than across sociolinguistic groups. A high similarity was shown in end-users' preferences for breeding traits across the study area. Top key traits to consider in breeding varieties of S. dulcificum to meet various end-users' expectations in West Africa include fruit size and fruit miraculin content. These results constitute a strong signal for a region-wide promotion of the resource

Enhancing germination and seedling growth in

Introduction. Many fruit trees with a hard seed coat exhibit seed dormancy, posing problems for their regeneration. Vitex doniana, an indigenous multipurpose but threatened fruit and vegetable tree that supports the livelihoods of many households in West Africa, is a typical example. Materials and methods. In our research, we evaluated five dormancy-breaking treatments. We tested the effects of sulphuric acid at 95% concentration (T1); 3 d sun-drying + 48 h soaking in tap water (T2); 3 d alternation of 8 h sun-drying + 1 h soaking in tap water (T3); 2 weeks sun-drying with regular watering in the daytime (T4); and physical shock (T5). These treatments were compared with two controls (T0 and Tc), with seeds from two different sources. The germination percentage, mean germination time, time to first germination and time to threshold germination (20%) were compared; the seedling height, diameter and biomass produced were monitored for 15 weeks. We used generalised linear models and correlation tests to compare the effects of the various treatments on germination and seedling growth. Results and discussion. T3 significantly enhanced seed germination in V. doniana (72% after 12 months). T4 best promoted homogeneity in germination (p < 0.01), followed by T3. The best seedling growth was obtained with T4 and T3. Alternation of sun-drying followed by soaking of seeds, a technique with almost no cost, improved seed germination in V. doniana and, in 33 d, just over 1 month, 20% germination can be achieved. Vitex doniana is a fast-growing species (at the nursery stage), in contrast to the common opinion. Conclusion. Our method should be further investigated to assess the adequate soaking and drying length so as to speed up germination and reach homogenous cohorts