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: irvingia
Domestication of Irvingia gabonensis: 3. phenotypic variation of fruits and kernels in a Nigerian village
Domestication of Irvingia gabonensis, a fruit tree grown in agroforestry systems in West and Central Africa, offers considerable scope for enhancing the nutritional and economic security of subsistence farmers in the region. Assessments of phenotypic variation in ten fruit, nut and kernel traits were made on twenty-four ripe fruits from 100 Irvingia gabonensis trees in Ugwuaji village in southeast Nigeria, a center of genetic diversity for this species. There were important differences between the young planted trees of this study and the older unplanted trees of a similar study in Cameroon. Significant and continuous tree-to-tree variation was found in fruit mass(69.0–419.8 g), flesh mass (59.5–388.8 g), nut mass (9.5–40.6 g), shell mass (4.9–30.9 g) and kernel mass (0.41–7.58 g); fruit length (49.2–89.3 mm) and width (46.2–100.5 mm) and flesh depth (12.9–31.4 mm), as well as considerable variation in flesh colour, skin colour, fruit taste and fibrosity. Some fruits were considerably bigger than those found in Cameroon. These quantitative results will help in the development of cultivars within participatory approaches to agroforestry tree domestication, and so promote poverty alleviation and sustainable agriculture.
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.
Analysis of genetic diversity in accessions of Irvingia gabonensis (Aubry-Lecomte ex O’Rorke) Baill
Amplified fragment length polymorphism (AFLP) was used to assess genetic diversity and relationshipsamong 15 accessions of Irvingia gabonensis collected from Cameroun, Gabon, and Nigeria. TwelveAFLP+3 primers produced 384 polymorphic fragments. Average genetic distance (AGD) between the 15accessions was 58.7% (32-88%). AGD and range of genetic distance among accessions from Cameroun,Nigeria and Gabon were 62% (53-76%), 52% (32.3 – 84.8%) and 50% (45-53%), respectively, indicatingmore genetic diversity in Cameroun than Nigeria and Gabon. The unweighted pair-group method of thearithmetic average (UPGMA) and principal coordinate analysis (PCO) showed a clear distinctionbetween the Gabon and Nigeria accessions into two separate clusters, with accessions from Camerounoverlapping them. Principal coordinate analysis (PCO) indicated a closer relationship betweenaccessions from Cameroun and Gabon. In general the Cameroun germplasm appears to be a bridgebetween the genetically isolated Nigeria and Gabon accessions. This overlap of Gabon and Nigerianaccessions by the accessions from Cameroun may be an indication that Cameroun is the center ofdiversity of I. gabonensis and also the primary source of original materials grown in the other countries.More collection in Cameroun is necessary to ensure the optimum collection and preservation of theexisting genetic diversity in I. gabonensis.