Farmers\' Participation In Ex-Situ Conservation Of Indigenous Fruit Trees In Southern Nigeria

Farmer Participatory Research (FPR) is a new approach, which the World Agro forestry Centre (ICRAF), International Institute of Tropical Agriculture (IITA), NGOs and farmers are using to effectively design and implement community-based conservation project in Nigeria prior to ex-situ conservation. Socioeconomic and market surveys were conducted and base-line data collected in seven communities. Results from seven pilot sites in Southern Nigeria indicate that community farmers readily adopted tree domestication, increasingly acquired skills, easily established community nurseries, enthusiastically identified and conserved economic fruit trees, including Irvingia gabonensis, Irvingia wombolu, Dacryodes edulis, Chrysophyllum albidum, Garcinia kola, in the rural communities. The participatory approach, which involves rural farmers direct involvement in decision making and in the development of suitable practices, is not only effective in reducing genetic loss, but also increases availability and yields of indigenous fruit trees (non-timber forest products). Journal of Agriculture and Social Research Vol. 4 (2) 2004: 33-4

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

Falsifikat einer Fürsorgekarte KM-O.965-3

Falsifikat einer Fürsorgekarte, Jahr 193

Domestication of Irvingia gabonensis: 4. tree-to-tree variation in food-thickening properties and in fat and protein contents of dika nut

Dika nut kernels were extracted from the nuts of 24 Irvingia gabonensis fruits collected from 151 trees in three villages in Cameroon and Nigeria. Methods were developed for the milling, de-fatting, hot-water pasting and rapid visco-analysis of the samples, to simulate the cooking of dika nut meal as a food-thickening agent. Two parameters (viscosity and drawability), thought to relate to the soup-thickening quality of dika nut meal, were derived from the traces. The samples exhibited significant tree-to-tree variation in viscosity, drawability and fat content, and differences between their villages of origin were significant. Thickening was found not to be directly associated with protein content. Similarly, the fat content did not contribute to the thickening properties at temperatures above fat melting point. Fat determination and fatty acid profiling indicated that the fat content ranged from 37.5% to 75.5% and identified myristic and lauric acids as the major fatty acid components. This study is part of a wider tree domestication project characterising tree-to-tree variation in fruit, nut and kernel traits of I. gabonensis with the aim of improving the livelihoods of subsistence farmers

Full length Research Paper - 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 relationships among 15 accessions of Irvingia gabonensis collected from Cameroun, Gabon, and Nigeria. Twelve AFLP+3 primers produced 384 polymorphic fragments. Average genetic distance (AGD) between the 15 accessions 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, indicating more genetic diversity in Cameroun than Nigeria and Gabon. The unweighted pair-group method of the arithmetic average (UPGMA) and principal coordinate analysis (PCO) showed a clear distinction between the Gabon and Nigeria accessions into two separate clusters, with accessions from Cameroun overlapping them. Principal coordinate analysis (PCO) indicated a closer relationship between accessions from Cameroun and Gabon. In general the Cameroun germplasm appears to be a bridge between the genetically isolated Nigeria and Gabon accessions. This overlap of Gabon and Nigerian accessions by the accessions from Cameroun may be an indication that Cameroun is the center of diversity 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 the existing genetic diversity in I. gabonensis

Domestication of Irvingia gabonensis: 2. The selection of multiple traits for potential cultivars from Cameroon and Nigeria

Ten fruit and kernel traits were assessed in 24 fruits of each of 152Irvingia gabonensis trees in three distinct populations inwest and central Africa [2 populations of non-planted trees in Cameroon:Nko'ovos II (21 trees) and Elig-Nkouma (31 trees) and 1 population ofplanted trees in Nigeria: Ugwuaji (100 trees)]. Strong relationships were foundbetween fruit weight and other fruit traits (e.g. flesh weight[r 2 = 0.99: P < 0.001],fruit length [r 2 = 0.74–0.83:P < 0.001], fruit width[r 2 = 0.77–0.88: P< 0.001]). In contrast, relationships between kernel weight and otherkernel/nut traits (e.g. shell weight and nut weight) were found to be weak[r 2 = 0.009–0.37, P =0.058–0.001], with the exception of nut weight at Nko'ovos II(r 2 = 0.65, P < 0.001).Relations hips between fruit and kernel traits (fruit massv. kernel mass, fruit mass v. shellmass, flesh mass v. kernel mass, nut massv. fruit mass and flesh depth v.kernel mass) were found to be very weak. This indicates that domesticationthrough the selection and vegetative propagation of multiple-trait superiorphenotypes is unlikely to be able to combine good fruit characteristics and goodkernel characteristics within cultivars. Consequently, domestication activitiesshould independently focus on ideotypes representing: lsquofresh fruitrsquotraits, and lsquokernelrsquo traits, that combine high values of thedifferent fruit and kernel characteristics respectively. Evidence from thisstudy indicates that selection of the three trees closest to the fruit ideotypeper village as the mother plants for vegetative propagation and cultivardevelopment, should give village level gains of 1.3 – 2-fold in fruitmass, and up to 1.5-fold in taste. Similarly for the kernel ideotype, selectionof the three trees with the best fit would give potential gains in kernel massof 1.4 – 1.6-fold