2nd Year Progress Report
1st April 2008 – 31st March 2009

Introduction
The research project aims to investigate and develop methods of improving the management and utilisation of selected indigenous fruit trees of economic value in Eastern Africa with the participation of local communities. The selected tree species include: Balanites aegyptiaca (The Desert Date) in Uganda, Borassus aethiopum (African Fan Palm) in Sudan, Cordeauxia edulis (Yehib) in Ethiopia, Sclerocarya birrea (Marula) in Tanzania, and Vitex payos (Chocolate Berry) in Kenya.

This report presents the results of the second year achievements of the project. The project activities are well underway and significant achievements have been made in all the five participant countries.

1. Research achievements made during the 2nd year and plans for 3rd year

1.1 Ethiopia
The study site in Ethiopia is very close to the border with the neighboring war-torn Somalia and there are also rebel activities on the road from Jijiga to the study site (no alternative road). The security situation around the study area, therefore, remains unstable. However, the researcher managed to visit the study site twice during the second year of the project whenever rebel activities were low. He managed to collect the field data by exploiting to the fullest this window of opportunity.

Preliminary assessment of the phenology study indicated that Cordeauxia edulis is an evergreen small tree or shrub. It flowers and fruits twice a year: flowering between March and April and October and November and fruiting between April and May and November and December. This is due to two rainy seasons: March to May (140 mm) and September to November (80 mm) and total annual rainfall is 229 mm. Fruits were harvested at the end of each fruiting period and yield ranged from 0.2 to 2 kg per tree.

Further analysis of the data on the population survey of C. edulis revealed that the tree is multi-stemmed and the number of stems per tree ranged from 11 to 17. Average total height of the tree ranged from 1.40 to 1.95 m, and crown diameter from 1.1 to 2.4 m. The regeneration ranged from 0 to 4 seedlings per ha.

Tree species that are associated with C. edulis included Acacia horrida, Acacia tortilis, Balanites scillin, Boswellia neglecta, Boswellia microphylla, Cassia obovata, Commiphora horrida, Commiphora erytherae, Commiphora candidula, Cordea africana, Euphorbia cuneata, Fagonia lahavari, Indogofera ruspolii, Sesamothamnus rivea and Terminalia orbicularis.

The soil of the study site was analysed and the soil textural class is sandy loam and K, Ca, N and OM were higher under the tree than outside.

The propagation trails conducted in Jijiga using seeds collected in 2008 showed some success. The highest germination of seeds (50%) was obtained using soil obtained from the study site. The second experiment in which seeds were pre-treated by socking in alcohol for ½ an hour then washing them with distilled water showed that the rate of germination was enhanced, the highest percentage being (60%) which was achieved in soils from the study site.

The results of a post-harvesting experiment carried out to identify improved methods of harvesting and storage showed that seeds harvested after drying on the tree and then treated with Neem leaves as herbicide before storage were not attacked by pests while seeds that were harvested fresh and stored without herbicide were fully attacked by pests by the end of 10 weeks of storage as reported by 89% and 97% of the research participants (local people), respectively.

Another experiment on propagation is planned for the 3rd year. This will involve application of different watering regimes (watering twice a day, once a day, two days interval and three days interval), combined with pre-treatment of seeds (socking in acid and control without pre-treatment) and shading (under full shade, partial shade and a control without shade).

1.2. Kenya
Fruit yield per tree of Vitex payos in Kenya was assessed by counting all fruits on a tree before the fruits ripened and started falling on the ground. For this, two methods were used; 1) counting all fruits on a tree and 2) randomly sampling of some branches and counting the fruits on those branches. The results indicated that trees with many main branches and of high diameter produced fewer fruits. Trees with many secondary branches but of small diameter and few main branches produced more fruits.

The amount of pulp that could be realized from a given quantity of fruits was also assessed. The mean pulp weight is 48.3% of the total fruit weight. Estimation of the fruit numbers using random branch sampling method is planned for the 3rd year.

Superior quality trees were selected using local people’s selection criteria to supply the scions needed for the grafting work and cuttings for vegetative propagation trials. For the grafting work seedlings were raised in the nursery to be used as rootstocks. These seedlings were grafted using scions collected from the selected superior mother trees.

Out of the 81 nursery grown rootstocks that were grafted, only 24 were successful using top wedge grafting technique. Out of the 24 successful grafts, three produced flowers while still in the non-mist propagator. These grafts were removed from the non-mist propagator and planted in the field. Their performance is being monitored.


The grafting trial using naturally regenerated wildlings as rootstocks in the field was not carried out because the wildings were small and scattered to allow proper setting up of a grafting trial among them.

Four trials were carried out on cuttings of V. payos using rooting enhancing chemicals, different rooting medium, different mother trees and different heights on the mother tree where the cuttings were obtained from. None of the cuttings rooted. The trial shall be repeated every month next year to determine if there is an appropriate time when cuttings should be collected from the field.

The market surveys revealed that in Mwingi and Kitui districts, V. payos fruits are not only locally consumed but are also sold in the local markets. The marketing of these fruits is a haphazard process with prices varying from place to place. A 20 litres bucket of fruits normally sells for between 80 and 150 KES (£1 = KES 113) in Ikanga and up to 200 KES in Kalundu market, Kitui. However, the same quantity of fruits in Mwingi sells for between 25 to 100 KES.

The market survey also revealed that no processing of V. payos fruits has been done by local prople, safe for some minor attempts by children to make some juice. To raise awareness on the potential of these fruits, the preparation of V. payos jam was demonstrated in public in all the study areas. The emphasis was to inform the farmers that with only a single external input, sugar, it was practically possible to prepare the jam as a means of adding value to the tree. The most challenging step in the whole process is the separation of pulp from the nuts. Using local artisans, a potato peeler is being modified to operate manually to separate the pulp from the seeds. This equipment shall be demonstrated on the farms during the 2009 fruit season between April and June.

1.3. Sudan
Halook is one of the main products of Borassus aethiopum. These are young shoots that are grown traditionally by sowing seeds of B. aethiopum on mounds. The young shoots are eaten after cooking as a delicacy and are extensively traded on local markets.

Halook was grown in the nursery using the same traditional mounds for six weeks and its nutritional properties were analysed at weekly intervals and the results showed that the highest quantity of crude protein (40.41%) and fibre (36.69%) were obtained by the end of 6 weeks of growth.


B. aethiopum were intercropped with cowpea and sorghum using trees of different ages (young & mature) and different planting spacing (one, two and three meters from the base of the tree). Age of tree did not have effect on the yield of crop. But distance had significant effect, the highest yield of crop being close (1m) to the base of the tree: 1.39 and 2.98 tons per ha for sorghum and cowpea, respectively. The yield of sorghum outside the tree crown (control) was, however, higher than under shade, in contrast to cowpea. This may be due to difference in shade tolerance.

The results of soil analysis of the study sites showed that the textural classes of the top soil (0-15 cm) were sandy clay in two sites and sandy loam in one site and the organic matter content ranged from 0.19 to 0.46 ml per litre and pH from 7.02 to 7.16.

An experiment to test improved techniques of growing B. aethiopum has been established in the nursery. The following seed pre-treatments were applied: (1) boiling, (ii) soaking in cold water, (iii) scarification, and (iv) nipping. A potting mixture of sand and clay at the ratio of 2:1 was used and farm yard manure was added to the mixture. These treatments were arranged in split plot design with three replications. Assessments of germination and seedling development are ongoing.

Data collection and analysis on population status, phenology, local knowledge and market surveys are also ongoing.

1.4. Tanzania
Using local peoples’ criteria, 20 superior mother trees of Sclerocarya birrea were selected from which cuttings were obtained for vegetative propagation experiment. After the vegetative propagation experiment the rooted cuttings were supposed to be used as rootstocks for grafting of scions from the selected superior mother trees of S. birrea. The vegetative propagation experiment was conducted using cuttings obtained from distal parts of branches of the mother trees in a non-mist propagator, but was not successful. Air-layering technique was also applied, but the air-layers failed to root. After consultation with experts from ICRAF and the project supervisors it was decided to abandon the cutting and air-layering experiments. A similar experiment done by ICRAF in 2000 to 2003 resulted in similar results.

The propagation trial is now focusing on grafting of both male and female scions from selected superior mother trees onto naturally regenerated seedlings in farmers’ fields using two methods of grafting, namely top vs whip & tongue grafting, on different sizes of rootstocks (wildings). The results are positive and success has been almost 99% so far. The performance of the grafts is being monitored by assessing changes in leaf number and colour and increase in length of the grafted scions.

Questionnaire survey to illicit local knowledge on use and management of S. birrea has been done and data analysis is underway. Soil samples have been collected from each site and analysis is being done at Morogoro. Total direct fruit counting and measurement of weight and size of fruits are being done in all the three sites. Laboratory analysis of the nutritive properties of the fruits will be done at Morogoro and Bangor. Phenological assessment is also ongoing.

1.5. Uganda
Four Balanites aegyptiaca populations have been inventoried. Preliminary results showed that in both study sites (Ajumani and Katawi districts) there are generally more B. aegyptiaca trees in the wild than on farm. The average stocking density was 9 and 3 trees/ha in Ajumani and Katawi, respectively. Tree diameter at breast height ranged from 10 cm to 90 cm. Tree height ranged from 2 to 15 m while crown diameter varied from 1.5 to 22 m. Diameter class distribution revealed fewer trees in the lower (10 – 19 cm) and higher (>54 cm) diameter classed but more trees in the mid diameter classes 20 – 34 cm, 35 – 44 cm, and 45 – 54 cm. This shows a low recruitment of saplings into trees. Crown diameter is generally larger for Adjumani tree populations than those in Katakwi. This can be explained by the repeated lopping of trees in Katakwi to provide a leafy vegetable. 70% of the trees in Katakwi have been looped to obtain a leafy vegetable. B. aegyptiaca was found to regenerate by both seed and coppicing. In both study sites, B. aegyptiaca was found to be the most dominant species. It was more abundant in Adjumani district where it constituted over 72% and 58% of the tree vegetation in the wild and on farm, respectively. In Katakwi district, Balanites constituted 40% and 42% of the tree population in the wild and on farm, respectively. In Adjumani district, B. aegyptiaca was commonly associated with Lannea schwenfurthii, Tamarindus indica, Acacia sieberiana, Sclerocarya birrea, Combretum collinum and Zyzyphus abyssinica. In Katakwi district it was commonly associated with Combretum schumanii, Acacia sieberiana, Acacia seyal, Acacia gerrardii, Euphorbia candelaberum, Lannea barteri and Tamarindus indica.

The results so far collected on phenological events for B. aegyptiaca indicated that it is a semi-deciduous tree. Flowering is initiated around January and reaches a peak in Feb-March. Fruiting starts around February and the fruits are fully developed after 7 - 9 months. Fruit repining sets in around November, reaches a peach in December – January and ends in late March.

Assessment of the cutting experiment in the non-mist propagation experiment showed that 11% and 16% of the stem cuttings rooted in the sand and pine bark growth media, respectively, after ten weeks.


All the cuttings which rooted were transferred into a standard transplant soil mixture in polythethene tubes and kept at 75% shade green house. Although they were watered trice daily, all the plants, however, dried up after two weeks. Grafting using one year old B. aegyptiaca seedlings raised from seed in the nursery as rootstocks was, however, not a success. Grafting experiment will be repeated during the wet season (April - May 2009).


The results of the germination experiment using various seed pre-treatment techniques and conducted in a green house showed that there is probably no need for B. aegyptiaca seed pre-treatment. After two weeks observation, no germination was recorded under pre-treatment (i) boiling for 10 minutes and left to cool in water for 4 hours, 62.5% under treatment (ii) soaking in cold water at room temp for 24 hours, 59.5% under treatment (iii) soaking in hot (boiling) water for 12 hours, and 63% under treatment (iv) sowing in pots without any treatment (control).

Activities undertaken under on-farm experiment on the management of B. aegyptiaca seedlings including routine weeding and manure application at six monthly intervals did not enhance the growth rate of seedlings, the maximum height being only 80 cm. The growth nature of the plant, dying of the leading stem and re-sprouting of several stems is a challenge in growth monitoring. Livestock browsing, especially by goats has also been a challenge.



Data entry and analysis on the marketing study is currently on-going. Nutritional analysis of leaves and fruits of B. aegyptiaca with supplementary funding from Makerere University (Carnegie Institutional Development Program) are also underway and are planned to be completed by June 2009.

2. Dissemination

2.1 Ethiopia
A seminar on C. edulis was given at Somali Region Pastoral and Agro-pastoral Research Institute (SoRPARI), Jijiga to scientists and technicians. A 40 minute documentary on the species was broadcasted on Somali programme of the Ethiopian Television. A newspaper article has also been published in a local Somali language newspaper, Dhamball, Page 6.

2.2 Kenya
An article on V. payos has been published in a national newspaper, The People Daily, Page 14.

2.3. Sudan
Two Seminars on B. aethiopum were given: one at El Obeid Research Station and the second at the Forestry Research Centre in Khartoum to scientists and technicians. An article has also been published in a national newspaper, The Citizen, Page 19.

2.4. Tanzania
An article on S. birrea has been published in a national newspaper, Daily News, Page 9. It is also available online at:
http://www.dailynews.co.tz/feature/?n=1076&cat=feature

2.5. Uganda
An article on Balanities has been published in a national newspaper, Sunrise, Page 7.

Two seminars were given. One was at Katakwi district council hall to members of the District Environment Committee, Heads of Natural Resources-based Departments, and NGO representatives. The second was at Adjumani district council hall to the District’s Heads of Departments, Sub-county representatives, NGO representatives and the Chief Administrative Officer. The extracts of the Adjumani seminar were aired out on local radio. The major outcome of both seminars was the issuance of Tree Planting and Protection Ordinance and Environment and Natural Resources Protection Ordinance in Katakwi and Adjumani, respectively. A third seminar was given at the National Forestry Resources Research Institute, Mukono to research scientists and technicians.