Poverty has many faces and poverty reduction many pathways in different contexts. Lack of food and income interact with lack of access to water, energy, protection from floods, voice, rights and recognition. Among the pathways by which agricultural research can increase rural prosperity, integrated natural resource management deals with a complex nexus of issues, with tradeoffs among issues that are in various stages of denial, recognition, analysis, innovation, scenario synthesis and creation of platforms for (policy) change. Rather than on a portfolio of externally developed ‘solutions’ ready for adoption and use, the concept of sustainable development may primarily hinge on the strengths and weaknesses of local communities to observe, analyse, innovate, connect, organize collective action and become part of wider coalitions. ‘Boundary work’ supporting such efforts can help resolve issues in a polycentric governance context, especially where incomplete understanding and knowledge prevent potential win-win alternatives to current lose-lose conflicts to emerge. Integrated research-development approaches deal with context (‘theory of place’) and options (‘theory of change’) in multiple ways that vary from selecting sites for studying pre-defined issues to starting from whatever issue deserves prominence in a given location of interest. A knowledge-to-action linkage typology recognizes three situations of increasing complexity. In Type I more knowledge can directly lead to action by a single decision maker; in Type II more knowledge can inform tradeoff decisions, while in Type III negotiation support of multiple knowledge + multiple decision maker settings deals with a higher level of complexity. Current impact quantification can deal with the first, is challenged in the second and inadequate in the third case, dealing with complex social-ecological systems. Impact-oriented funding may focus on Type I and miss the opportunities for the larger ultimate impact of Type II and III involvements.
Tag: dacryodes edulis
Evidence that subsistence farmers have domesticated indigenous fruits (Dacryodes edulis and Irvingia gabonensis) in Cameroon and Nigeria
Ten fruit and kernel traits were measured in 152 Irvingia gabonensis and 293 Dacryodes edulis trees from 6 villages in Cameroon and Nigeria. Frequency distribution curves were used to examine the range of variation of each trait of each species in each village and aggregated into national and regional populations. There were differences between the village sub-populations, with regard to the normality (e.g., mean kernel mass of D. edulis) or skewness (e.g., mean flesh depth of D. edulis) of the distribution curves and in the degree of separation between the individual village populations along the x axis, resulting in the development of a bimodal distribution in the regional population. For all traits, populations of both species differed significantly between countries, but only in D. edulis were there significant differences between the Cameroon populations. On the basis of the results of this study, D. edulis can be said to be virtually wild in Nigeria but semi-domesticated in Cameroon, while I. gabonensis is wild in Cameroon and semi-domesticated in Nigeria. These results are discussed with regard to a hypothesis that the range and frequency of variation in the different populations can be used to identify five stages of domestication. From a comparison of the frequency distribution curves of desirable versus undesirable traits, and statistically identifyable changes in skewness and kurtosis, it is concluded that as a result of the farmers’ own efforts by truncated selection, D. edulis is between Stages 2 and 3 of domestication (with a 67% relative gain in flesh depth) in Cameroon, while I. gabonensis in Nigeria is at Stage 2 (with a 44% relative gain in flesh depth). In this study, genetic diversity seems to have been increased, and not reduced, by domestication.
Tree domestication in tropical agroforestry
We execute tree ‘domestication’ as a farmer-driven and market-led process, which matches the intraspecific diversity of locally important trees to the needs of subsistence farmers, product markets, and agricultural environments. We propose that the products of such domesticated trees are called Agroforestry Tree Products (AFTPs) to distinguish them from the extractive tree resources commonly referred to as non-timber forest products (NTFPs). The steps of such a domestication process are: selection of priority species based on their expected products or services; definition of an appropriate domestication strategy considering the farmer-, market-, and landscape needs; sourcing, documentation and deployment of germplasm (seed, seedlings or clonal material); and tree improvement research (tree breeding or cultivar selection pathways). The research phase may involve research institutions on their own or in participatory mode with the stakeholders such as farmers or communities. Working directly with the end-users is advantageous towards economic, social and environmental goals, especially in developing countries. Two case studies (Prunus africana and Dacryodes edulis) are presented to highlight the approaches used for medicinal and fruit-producing species. Issues for future development include the expansion of the program to a wider range of species and their products and the strengthening of the links between product commercialization and domestication. It is important to involve the food industry in this process, while protecting the intellectual property rights of farmers to their germplasm.
Vegetative propagation of Garcinia lucida Vesque (Clusiaceae) using leafy stem cuttings and grafting
Garcinia lucida Vesque (Clusiaceae) is a tree species that is highly valued for its medicinal properties by rural households in the humid forest zone of Cameroon. However, the unsustainable exploi – tation of the species threatens its long-term regeneration. This study focuses on its vegetative propagation via stem cuttings in non-mist propagators and through grafting. The study tests the effects of three rooting media (sand, sawdust, sand + sawdust (1/1); three leaf sizes (0,25 and 50 cm 2 ); and three types of hormone [indole butyric acid (IBA), indole-3-acetic acid (IAA) and naphthalene acetic acid (NAA)], applied as a single dose. Furthermore, three grafting techniques (cleft, side tongue and whip-and-tongue grafting) were tested. All experiments were designed as completely randomized blocks with three replicates. Results showed that cuttings require a medium that has low water holding capacity and high porosity, and a leaf area of 50 cm 2 and NAA treatment; grafting success was affected by the technique used, with top cleft grafting yielding a 100% success rate. From this preliminary study, it is concluded that G. lucida is amenable to vegeta – tive propagation by cuttings and grafting
Biophysical characterisation of dacryodes edulis fruits from three markets in Cameroon
Studies were done in order to assess variation in fruit size and weight, nut size andweight and determinate relationships between these characteristics and price using 149samples of Dacryodes edulis fruits from three markets at the peak of season inCameroon. 50 samples per market in two markets (Mfoundi market [Yaonde] andMakenene centre market) and 49 samples in Makenene East market were boughtrandomly from traders. The measurement of 10 characteristics of 24 fruits per sampleidentified significant variation in fruit size and weight and nut weight in each market.Fruit price was found to vary with flesh mass, fruit mass and fruit size in retailersmarkets while wholsalers don’t take into account fruit variability. In contrast, pulp priceper kg was negatively correlated with flesh weight in wholesalers’ markets. The mostfrequent skin colour was “georgetown lime” (29A7 in the Methuen colour code) and themost frequent flesh colour was violet (18D6 in the Methuen colour code). From thisstudy, Dacryodes edulis fruit ideotype fetching highest price in the retailers markets ischaracterized by length, flesh and fruit mass and white skin colour.
African plum: Dacryodes edulis
BOTANIC DESCRIPTIONDacryodes edulis is a medium-sized, evergreen tree attaining a height of 18-40 m in the forest but not exceeding 12 m in plantations. It is generally branched from low down, with a deep, dense crown. The bole is rather short, slightly fluted, 50-170 cm in diameter and more or less sinuous. The scented, pale grey, rough bark exudes a whitish resin. Buttresses are absent.Leaves compound, imparipinnate, with 5-8 pairs of leaflets; glossy above, pubescent, the pubescence disappearing with age.Flowers subtended, 3 lobed, conspicuous, caducous brow bracts, fragrant, about 5 mm across, trimerous except for the ovary, arranged in dense, ferruginous, stellate-tomentose inflorescence; sepals 3, brown; petals 3, cream-yellow; stamens 6, white; disc 6 lobed, surrounding the 2-celled, glabrous ovary; inflorescence axis 10-42 cm long or longer, deeply grooved.Fruits ellipsoidal drupes rather variable in size, 4-12 x 3-6 cm, resembling olives; exocarp thin, pink, becoming dark blue to violet at maturity; pulp firm and thin.