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Research Article | | Peer-Reviewed

Gum Arabic Research in Sudan During the Period 2000-2025 a Review Paper for Some of Research Activities During the Period 2000-2025

Kamal Eldin Mohammed Fadul*,  Muneer Elyas Siddig Eltahir,  Idris Musa Adam,  Abbas Hassan Ali,  Hatim Abdalla Elkhidir,  Mustaffa Abdalla Nasreldin,  Sona Mohammed Fadual,  Mohammed Mukhtar Ballal
Published in American Journal of Agriculture and Forestry (Volume 13, Issue 3)
Received: 9 June 2025     Accepted: 25 June 2025     Published: 19 July 2025
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Abstract

This paper is an attempt to review some of the research work that was carried out by the Gum Arabic Research Division (GRD) during the period 2000 to 2025. The objectives is to give a highlight about the research finding that provided by the Gum Arabic Research Division and to disseminate these finding to the gum producers, stakeholders such as companies, forest administrations, producers association and the other relevant research institutes. During the period 2000-2025 many research excrement’s were carried out by the gum arabic research scientist at El-Obeid, Kadugli and Nyala Research Stations. These experiments include tapping tools, date of tapping, tapping intensity, position of tapping (branch, lower stem, middle stem, and higher stem), tapping direction, the relationship between climatic factors, tapping and gum arabic yield, provenances trails and agroforestry trails. For tapping tools, the Sonki (new innovative tool developed by GRD) is found as a best tool for tapping Acacia senegal trees. It is reported that it has muti-function where it could be used for tapping the tree and harvesting the gum. The GRD was found that gum arabic yield was greatly influenced by tapping date, the gum yield (g/tree and g/picking) was higher when the trees were tapped on the 15th of October and 1st of November compared with other date of tapping. The GRD found that gum arabic yield prediction shortly before or after tapping is a achievable either by knowing the commencement of tapping or by knowing yield of the first picking. For the effect of tapping in various azimuth angles on gum arabic yield we found that gum yield of Acacia senegal increase by 67.6 and up to two folds as due to tapping in the Eastern and Western Sides of the branches towards direct sun light. 15 Acacia senegal provenances were examined in the nursery and under field conditions to identify which provenances that capable to grow and survive under a diverse environmental conditions at Eldamokey forest reserve. All A. senegal provenances gave a higher survival percentage of more than 90% under the dry climatic conditions at the experimental site. For agroforestry research it was found that intercropping of of Acacia senegal with groundnut, sesame and roselle provide a good household income from gum arabic production which can easily compensate for other crop yield losses. For tree spacing the finding from GRD indicated that crops yield and straw were affected by tree spacing thus recorded higher yield under wider spacing compared with the narrow ones. LER was higher under agroforestry system as compared to mono-cropping. The study concluded that gum arabic yield was greatly influenced by tapping date and tapping intensity. The gum yield of Acacia senegal increase due to tapping in the Eastern and Western Sides of the branches towards direct sun light. From and economical point of view, it is recommended that roselle and sesame can be intercropped with A. senegal.

Published in American Journal of Agriculture and Forestry (Volume 13, Issue 3)
DOI 10.11648/j.ajaf.20251303.12
Page(s) 152-168
Creative Commons

This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.

Copyright

Copyright © The Author(s), 2025. Published by Science Publishing Group
Previous article
Keywords

Gum Arabic, Date of Tapping, Tapping Tools, Tapping Intensity, Provenances Trails, and Agroforestry Research

1. Introduction
Sudan is the world’s largest producer of gum arabic, which is one of the four important agricultural export commodities from Sudan, along with livestock, cotton and sesame. Over the last 20 years, gum arabic export value amounted on average to US$ 40 million annually. While there has been government intervention in the marketing of all agricultural exports in the past, gum arabic is the only one for which government controls remain. Historically, Sudan was known to be a major gum exporter, producing more than 80 percent of the supply in the world market
[9, 18, 19]
.
Gum arabic is mostly produced by small-scale farmers in traditional rain-fed farming areas (central and western Sudan); they represent up to 20 percent of Sudan’s population, or around 6 million people, and are among the poorest and most vulnerable to food insecurity
[6]
.
Small-scale farmers who give priority to food crop production (usually sorghum or millet) to secure family nutritional needs but seek other sources of income to meet the household’s basic needs other than grains. In addition to the direct financial returns, they cultivate gum arabic because this activity constitutes a crop diversification strategy to mitigate crop failure, has substantial beneficial environmental impact, and is an important source of on-farm supply of fuel wood and livestock fodder.
Acacia senegal (L.) Willd is a widespread species. It occurs naturally in a belt 300 km wide extending through the southern frontier of the Sahara Desert, from Mauritania to Sudan, Ethiopia, Somalia; also in east Africa and extend southward to Mozambique, Transvaal, Natal; along the southern coast of Africa and Iran; and in Pakistan and western India
[10, 21]
.
In Sudan, Acacia senegal is found naturally in a belt commonly known as gum belt (Latitude 10° and 14° N) Figure 1. This broad ecological region represents a complex and diverse environment with regard to climate, soils, vegetation, animals and human activities
[5, 6]
. These factors were reported by
[27]
to have an impact on gum yield. The species occurs under annual rainfall of 280- 450mm in sandy soils, in Kordofan, Darfur and western White Nile. Also, under an average rainfall of 500mm in the central clay plains
[3, 5, 16]
, but can even grow under 200mm of rain, with 8-11 arid months, to 800mm
[26]
.
In this paper we are trying to give a highlight about the research that was carried out by the gum arabic research division during the period (2000-2025) and to disseminate the research finding to the gum producers, stakeholders such as companies, forest administrations, producers association and the other relevant research institutes.
2. Gum Arabic Research Division (GAD)
The gum arabic Research division was established in 1958 mainly to carry out research on gum. However, in the absence of a production division, it also had to carry out extension work to increase gum arabic production
[11]
. Generally, the gum Arabic research division has experienced administration changes, in 1975 it was put under the umbrella of the Agricultural Research Corporation (ARC) so that it could benefit from the multi-disciplinary interaction and focus only on research and extension. In 1982 it was absorbed in the western Sudan Agricultural Research Project (WSARP) which is a part from the ARC. Nowadays, the division was worked in four Research Stations in El-Obeid, Nyala, El Damazin Research Stations, and Soba Forestry Research Center. The responsibilities of the gum Arabic research division (GRD) include
1) Conducting gum and resin research
2) Formulating of development plans for gum arabic to ensure continuity and sustainability of yield
3) Improvement of the silvicultural and management practices of the gum arabic and other gum producing trees
4) Providing and dissemination of the technical information to small gum producers within the gum arabic belt.
5) Conservation of the promising A. seneal seed provenances
6) Improvement of agroforestry systems adaptable to the gum belt environment
7) Improvement of the local knowledge of small gum producers by supporting them by the new technologies that lead to sustainable management of gum resources
Figure 1. Isohytal map of the boundary of the gum belt.
3. Previous Research Work
3.1. Artificial Regeneration Trials
Some research work were done by the scientist in the gum arabic research division (GRD) covering seed germination, stumped transplant, seedling in soil blocks, sowing and planting in forest, sowing of seeds at grassland, sowing the seeds within the cultivation land, sowing in mechanized crop production schemes in Gedaref, in natural forests in Darfur, in agriculture experimental plots in El-Obeid town
[23]
.
3.2. Gum Tapping and Tapping Tools
Gum tapping is the traditional way of producing gum in Sudan. Usually the tapping is done for A. senegal (gum arabic tree) by using small Axe (Farrar) or by using the developed new hand tool called Sonki
[11]
. The Sonki is driven under the bark of the tree without penetrating the wood between the outer bark and inner cambium
[17]
. A strip of bark (30 to 40cm) is then removed causing wounds which stimulate gum exudation
[7]
.
The wound resulting from removal of the bark of the tree exposes the inner bark and the cambium of the tree to the external environment (light and wind) and hence the gum exudes cover the wound and thus the gum arabic is formed
[2]
.
The gum arabic Research Program at El-Obeid Research Station developed an alternative tapping tool. The tool is composed mainly of an iron part of about 20cm long with a sharp pointed apex (3cm long) with a tool handle of 2.5m (Figure 2). This tool is known as Sonki which was proved to be less damaging to the tree compared with the traditional axe. According to
[20]
95% of the Sonki users stated that "it is a good tool, save time, efficient, relevant to the tapping practice and functional". It was stated also the Sonki can be used for both tapping and collection. Moreover, women and teenagers could also use it. Sonki never recorded any damage to the trees compared with axe. Some producers mentioned that using Sonki increased the gum production. This tool is characterized by light weight, cheap in price and easy to access high branch.
Tapping was carried out at two intervals, the first tapping immediately after the rainy season (November) and the second tapping in summer (February)
[26]
. Tapping is usually done after the rainy season starting in October to mid of November.
3.3. Other Experiments
Other experiment has been carried out. The objectives were to enable more systematic comparison between different treatments, and to confirm or check the research finding obtained from the previous work
[11]
. These may be summarized as; germination of seeds and establishment of seedlings; effect of mulching on seed germination; shade tolerance of A. senegal compared with other three species among its natural association; the effect of rainfall and soil type on regeneration of Acacia senegal; regeneration of Acacia senegal by Tuangya, Comparative methods of establishment of Hashab plantation, trails on chemical weed control, provenance trails, the effect of fire and locust damage on gum production and other research activities
[23]
.
Most of the results of the experimental work of the GRD prior to its amalgamation with WSARP were documented. More recent reports written by the staff members of the GRD cover almost all aspects of gum arabic and are to be found in the archives of the Forest National Corporation (FNC), Khartoum, the Agricultural Research Corporation (ARC), Wad Medani, the Forestry Research Center, Soba, and gum Arabic Research Division at El-Obeid Research Station.
4. Recent Research Finding
4.1. Tapping Age and Tapping Intensity
Tapping of the gum tree generally starts when the trees are 3-7 years old with a height of about 1.2-3.7 m and diameter of 5cm
[6]
. However, the trees from coppice are tapped at the age of 3-4 years age, while trees from seedling are tapped at the age of 5 year. In addition, the trees grown naturally are tapped at the age of 6-7 years old. Gum yield varies considerably with variation in the genetically make up of the tree, its environment and management practices such as tapping methods and intensity of tapping.
The same author cited variable gum yield figures ranging from 0.1-2kg/ tree/ year as reported by different authors
[6, 21]
. The GRD investigated the effect of time and intensity of tapping (the number of branches tapped per tree), showed that earlier tapping as in mind October significantly increases gum yield. The mean yield was only 7.1-8.8kg/tree/ year in late tapping e.g. 30th November and 15th December, respectively
[8]
. The same author recommended that tapping the minimum number of branches per tree is necessary for sustaining yield without weakening the tree.
4.2. Determination of Optimum Date of Tapping
The time for tapping the tree is differs with local climatic conditions
[6]
. Rainfall and temperature variations were found to affect the time of tapping and consequently gum yield
[4]
.
Tapping is carried out after the rains or when the growth stops and the leaves become yellowish in colour and began to shed
[8]
. Late tapping after the cold spell is over, is done when the rainy season is too long resulting in continued growth. Tree defoliated by locust or browsed by camels are also delayed for tapping because they continue to grow instead of entering into a dormancy period, which precede gum exudation
[8]
.
The time of tapping is very critical and unless it is done timely. The farmers may lose the whole or part of his gum yield if he taps the tree lately. However the procedures followed in tapping is similar for both plantation and natural stands. Traditionally, the gum producers tend to tap late after harvest of their agricultural crops
[13]
.
GRD at El-Obeid and Kadugli Research Stations carried out several experiments for t determination of the optimum date of tapping, Adam and Fadl 2008/09 and 2009/010 studied the effect of tapping date for gum arabic production in South Kordofan State. They studied six tapping date (1 Oct, 15th Oct, 1 Nov, 15th Nov, 1 Dec and 15th Dec) a simple financial analysis of gross surpluses was used to evaluate the productivity and profitability of the different treatments.
The results of 2008/2009 season yields differed significantly by date of tapping (p<0.001) for all picking except the fifth picking (Table 1). Tapping on 15 October and 1 November yielded 1038.5 g and 482.3 g, respectively, both significantly higher than on the other tapping dates. The total gum yield (g/tree) in this season showed highly significant differences (p < 0.001) between the tapping dates. The highest total gum yield of 1038.5 g/tree was recorded when the trees were tapped on the 15th of October while the lowest total gum yield of 285.3 g/tree was recorded when the trees were tapped on the 1st of October. The effects of tapping date on A. senegal gum yield in the second season 2009 are shown in Table 2. Analysis of variance indicated significant differences (p < 0.001) between the dates of tapping on gum arabic yield. Tapping of A. senegal trees on the 15th of October and 1st of November gave a yield of 450.8g/picking and 274.6g/picking, respectively, which are significantly higher that on other dates of tapping. The total gum yield in the second season was significantly (p < 0.001) affected by the date of tapping. The highest total gum yield of 1164.8 g/tree was recorded when the trees were tapped on 15 October followed by 840.1 g/tree on 15 November, while the lowest total gum yield of 324.4 g/tree was recorded when the trees were tapped on 1 October Figure 5.
The combined analysis over season for the gum yield (g/picking) and for the total (g/tree) showed significant effects (p≤ 0.01) of tapping dates on gum yield. The higher total gum yield of 1360 (g/tree) was recorded when the A. senegal trees were tapped on 15 October followed by 661.2 (g/tree) on 1 November and the lowest gum yield of (386.1 g/tree) was recorded when the trees were tapped on 15 November. The gum arabic yield is highly governed by the end of the rainy season more that any specific calendar date. The difference in gum yield was attributed to high rainfall in two seasons which ranged between 350–750mm. Soils of the South Kordofan are almost clay soil (> 90% clay). This result can be used by farmers to gain more yield and to obtain 7−8 gum pickings rather than rely on 4- 5 pickings. In conclusion, A. senegal gum arabic yield was greatly influenced by tapping date, the gum yield (g/tree and g/picking) was significantly higher when the trees were tapped on the 15th of October and 1st of November compared with other date of tapping. These finding can be used to increase gum arbaic production in South Kordofan State and increase the household income especially during the dry season, this can compensate for crop failure.
In North Kordofan, The GRD studied the effect of date of tapping and stand type on gum yield. The highest yield obtained for all type of stands was found on early of (1 October to 1 November) tapping.
Figure 2. The Sonki innovated tapping tool which was developed by GRD, for tapping Acacia senegal.(Photo authorized Munner).
Table 1. Gum arabic Yield (g/picking) in South Kordofan State in Relation to Date of Tapping Season 2008/2009.

Date of Tapping

Gum Yield (g/picking)

Total gum (g/tree)

1

2

3

4

5

6

7

8

1st Oct

4.7

0.0

92.3

82.8

44.4

32.1

20.3

8.7

285.3

15th Oct

9.5

42.3

375.2

252.7

143.6

96.9

94.6

23.7

1038.5

1st Nov

48.6

45.6

155.8

107.2

56.9

40.6

18.5

9.1

482.3

15th Nov

52.2

55.9

84.3

94.2

63.5

44.2

25.0

1.7

421

1st Dec

45.3

66.4

127.0

116.9

59.8

36.9

0.7

6.7

459.7

15th Dec

43.1

127.0

83.4

78.4

62.0

0.0

1.3

0.0

395.2

Means

33.9

56.2

153

122.0

71.7

102.7

26.7

8.3

492.8

SE±

11.7*

8.8**

26.0**

18.3**

16.8*

7.9**

5.0**

2.4**

47.2**
Adam and Fadl, 2011, Journal of Forestry Research
Table 2. Gum arabic Yield (g/picking) in South Kordofan in Relation to Date of Tapping Season 2009/20010.

Date of Tapping

Gum Yield (g/picking)

Total gum (g/tree)

1

2

3

4

5

6

7

8

1st Oct

4.2

0.0

93.8

75.4

54.4

46.2

25.2

25.2

324.4

15th Oct

7.5

60.5

450.8

325.5

159.7

78.5

58.2

24.11

1164.8

1st Nov

34.2

93.0

274.6

161.1

120.0

84.4

54.1

18.7

840.1

15th Nov

24.2

80.6

235.0

166.1

101.7

72.0

33.2

1.3

714.1

1st Dec

29.0

80.4

218.4

192.7

77.3

52.0

0.0

1.0

650.8

15th Dec

37.0

60.3

197.8

122.3

48.1

0.0

0.0

0.7

466.2

Means

22.7

62.5

245.1

173.8

93.5

55.5

28.4

11.8

766.9

SE±

5.2 **

16.6*

48.8**

32.9**

25.6ns

11.8**

8.1**

3.0**

101.8**
Adam and Fadl, 2011, Journal of Forestry Research
4.3. Effect of Tapping in Various Azimuth Angles on Gum Arabic Yield in North Kordofan State
Gum yield varies greatly with differences in husbandry practices namely the time and intensity of tapping, and tapping methods
[7]
. The objective of this research work was to determine whether the gum arabic yield is affected by the method of tapping – specifically the site of the tapping in relation to the direction of sun light, and to recommend management guidelines to improve gum arabic production;
The GRD carried out an experiment at El Damokeya Forest Reserve for the seasons (2006/2007 and 2007/2008) to determine the effect of tapping in various azimuth angles on gum arabic yield in North Kordofan State. The results showed that there is a significant difference on all gum pickings and the percentages of the yielding trees in relation to tapping sides (Tables 3 and 4). Similarly, the gum yield and the number of yielding trees increased in the Eastern and Western sides tapping as compared with that of Northern and southern sides. The division found that the gum yield of Acacia senegal increase by 67.6 and up to two folds as due to tapping in the Eastern and Western Sides of the branches towards direct sun light. Similarly, the number of yielded trees was higher for those tapped in the East and West sides compared to trees tapped in the Northern and Southern sides
[1]
.
Table 3. Effect of tapping side on gum arabic yield (g/pick) in North Kordofan State (Season 2006/2007).

Tapping side

Pickings

Mean yield (g/pick)

1

2

3

North

27.4

22.6

40.0

36.9

South

31.2

27.7

41.8

41.3

East

61.6

63.6

49.4

64.4

West

51.8

65.5

48.6

65.0

Mean

43.5

44.9

45.0

53.6

SE±

3.27**

5.16**

2.67ns

2.79**
** Significantly at P ≤ 0.01, * Significantly at P ≤ 0.05 and ns not significant
Source: Proceeding of the 45th meeting of the National Crop Husbandry committee
Table 4. Effect of tapping side on gum arabic yield (g/pick) in North Kordofan State (Season 2007/2008).

Tapping side

Pickings

Mean yield (g/pick)

1

2

3

4

5

North

22.2

27.40

18.07

34.31

1.5

20.70

South

25.84

32.91

35.35

25.44

0.77

24.06

East

49.13

89.20

74.61

80.21

72.82

73.19

West

46.34

66.22

87.99

56.2

45.68

60.49

Mean

35.88

53.93

54.01

49.04

30.19

44.61

SE±

7.26 ns

12.3*

10.84**

11.35*

12.74

7.02**
** Significantly at P ≤ 0.01, * Significantly at P ≤ 0.05 and ns not significant
Source: Proceeding of the 45th meeting of the National Crop Husbandry committee
Figure 3. Farmers training in gum tapping and Tapping tools, North Darfur (Photo authorized Kamal).
4.4. Effect of Date of Tapping and Tapping Tools on A. Seyal Var Seyal Gum Yield
Acacia seyal var. seyal, locally known as talh, belongs to the family Mimosaceae. Under favorable conditions, the small to medium sized tree reaches a height of 17m, has a stem diameter of 60cm, and develops a characteristic umbrella- shaped crown. The bright green bark is covered with either a pale grey- green or rust-red powdery coat. The dark green leaves have 4 to 12 pairs of pinnae and 10 to 22 pairs of leaflets. Flowers have shiny yellow globose heads. Two or three are together at the leaf axils. Pods are slightly curved, light brown at maturation, and 10 to 15cm, long. The slash is bright red, mottled and exudes a yellowish gum
[15]
. No information is available about the tapping possibilities of A. seyal var. seyal for gum production.
Therefore, two experiments were conducted by GRD at Umfakarin forest reserve (South Kordofan) to investigate the effect of different tapping tools (makmak, axe, mofar and sonki) and tapping positions (low stem, middle stem, high stem and branches) on talh gum yield of A. seyal var. seyal. Trees were tapped on the 1st of November, and gum was collected four times (1st Dec., 1st Jan., 1st Feb. and 1st March) Figure 4. The results of the first experiment clearly indicate that the makmak is best tools for tapping Acacia seyal var seyal. In the second experiment, the middle stem tapping caused the highest gum yield with a total yield of 275 g/tree. The results indicate that tapping of A. seyal var. seyal is a promising technique for talh gum production Tables 5 & 6. The removal of bark to expose the wood surface stimulated gum excretion on A. seyal var. seyal in both experiments. The results of the first experiment clearly show that the tapping tool had a great influence on the amount of talh gum production of A. seyal var. seyal (Table 5). Over the season the trees produced the most gum when they were tapped with the makmak and the lowest when tapped with the sonki. In comparison to trees tapped with makmak, trees tapped with axe, mohfar or sonki produced 58, 59, and 75% less gum, respectively. The reasons can be seen in the wide edge on the top of the tool, which allows one to remove a big piece of the bark. The lowest gum yield was obtained from trees which were tapped with the sonki. The sonki was originally developed by the Agricultural Research Corporation in Sudan for tapping A. senegal. Today it is commonly used by tappers in Kordofan for hashab gum production. However, due to the different bark of A. seyal var. seyal compared to A. senegal, the sonki is not suitable for tapping A. seyal var. seyal
[14]
.
Table 5. Average yield of talh gum (g/ picking and g/tree) as affected by tapping tool at Um Fakarin forest reserve.

Tapping tools

Pickings

Total yield (g/tree)

1

2

3

4

Makmak

144.84a

30.7ab

132.02a

20.88c

328.6

Axe

55.64b

40.66a

35.68b

45.68ab

177.2

Mohfar

44.42b

40.78a

25.77b

58.64a

169.6

Sonki

29.83c

23.61bc

21.37b

30.16c

105.0

Position of tapping

Low stem

66.86a

52.18a

28.60ab

56.36ab

204.00

Middle stem

84.55b

98.42b

31.78a

60.76a

275.51

High stem

31.08c

35.36a

18.96c

32.45c

117.85

Branches

66.78a

37.08a

22.14b

36.04b

162.04
Table 6. The interactions of tapping intensity and tapping date on talh gum yield at Um Fakarin Forest Reserve.

Tapping date

Gum yield (g/tree)

Mean

Tapping intensity

2

4

6

8

1 November

203.38a

178.56a

183.99a

176.95a

185.72

15 November

144.56b

156.80b

177.80a

175.66a

163.71

1 December

120.28c

118.64c

89.47b

100.65b

107.26

Mean

156.07

151.33

150.42

151.09

152.23
* Means followed by the same letters on the same column are not significantly different at 5% level of probability.
Figure 4. Gum exudation from Acacia seyal var seyal tree (Photo authorized Kamal).
Figure 5. Gum yield from trees tapped by Sonki (Photo authorized by Kamal).
4.5. Gum Arabic Yield in Relation to Stand Type and Management in Western Sudan
The gum arabic yield varies as a result of complex factors of the physical, biological and socio-economic environment. The impact of these factors or some of them on gum arabic production has been reported by
[3, 4, 24, 27]
. Despite these attempts, yet there is information gap regarding the factors controlling gum arabic yield of the A. senegal tree. Presently the major problem facing the gum arabic industry in Sudan is a lack of reliable information on gum arabic yield and yield trends that can be used as a basis for monitoring gum arabic production
[8]
.
The gum arabic research programme carried out a comparative study of gum arabic yield trends per tree and pickings in relation to stand management (by farmers and by researchers) and type (natural and planted) in two locations in North Kordofan State for three consecutive seasons. In addition 8 years yield trend in relation to rainfall were compared based on the 1993-2000 gum yield data from 1400 trees. Although the gum yield followed the same trend over time in all stands at both locations, the gum yield from farm stand whether planted or natural was 47% to 60% lower than that from research stands. Late tapping reduced the gum yield by 40% and 50% at the two different locations, respectively Table 7. Yield was highly affected by rainfall, correlating positively with rainfall in six of the eight years of the study. These findings can be used for improving gum arabic yield through management interactions and for predicting yield in relation to stand type, management regime and rainfall.
Table 7. The interaction of tapping intensity and tapping date on gum yield (g/tree) at El Himaira natural stands.

Tapping date

Tapping intensity

Mean

1

2

3

4

5

6

7

8

1 Oct

27.0a

25.5a

31.4a

33.1a

23.3a

31.0a

33.6a

31.1a

29.2

15 Oct

48.3abc

36.5bc

54.9ab

46.6abc

53.0ab

29.7c

64.2a

38.6bc

46.5

1 Nov

34.3c

43.9abc

38.0c

58.4ab

41.9bc

60.9a

36.0c

34.8c

43.6

15 Nov

21.2a

28.8a

27.6a

31.1a

35.7a

35.9a

26.6a

35.6a

30.3

1 Dec

26.0a

22.5a

28.4a

26.6a

35.7a

32.7a

23.5a

16.6a

26.5

15 Dec

12.5a

18.9a

20.7a

21.9a

21.7a

26.8a

18.6a

32.5a

21.7

Mean

26.3

29.0

33.5

36.3

35.2

36.2

33.7

31.5
* Means followed by the same letters on the same column are not significantly different at 5% level of probability according to DMRT.
4.6. Research on Ecology of Acacia Senegal
A. senegal tree is the main species with vast geographical extent in the gum belt, which is about 300 km wide extending through the southern part of the Sahara Desert, from Mauritania to Sudan, Ethiopia, Somalia in east Africa, also in Iran, Pakistan and Western India
[21, 25]
. The herbaceous vegetation associated with the gum arabic tree varies considerably throughout the gum belt
[17]
. This association is belief in having a vital role in protection of the sandy soils beside a source of organic matter and nitrogen, which is necessary for sustained agricultural production. Therefore, proper and specific management of all ecological and environmental resources should be practiced to maximize the production and at the same time to minimize the losses of the trees. On the other hand, there is a strong held belief that presence of grasses under or around tree increases gum arabic yield. The more grasses exist, the more gum arabic yield expected. Based on these points of views, the GRD designed an experiment to investigate whether gum arabic yield from Acacia senegal is related, in a way or another, to the presence of grasses under the gum arabic tree.
The objective was to develop an understanding of the ecological effects of under-story vegetation and tapping date on the productivity of gum arabic from Acacia senegal as over story cover. The first factor was grass cover which was tested in four levels (100% and 50% grass cover in addition to bare and burnt). The second factor, date of tapping was tested in three levels namely (1st Oct, 15th Oct and 1st Nov). The first picking was done after 45 days from tapping and the gum yield up to seven pickings was collected at intervals of 15 days. The results showed that gum arabic yield was significantly increased by increase in density of grasses and the date of tapping was proved to have significant effect on gum yield Table 8. The early tapping gave more gum yield compared with the other dates of tapping. Furthermore, the density of grasses and the date of tapping have a significant effect on number of gum pickings.
Table 8. Gum arabic yield (g\picking) in relation to date of tapping and density of densities at El Demokeya Sites during 2004.

El Demokeya

Grass density

Date of tapping

Picking number

Total

1

2

3

4

5

6

7

100

1st Oct

89.4a

18.0e

13.9cd

7.3e

2.9f

8.3d

0.0c

139.8

15th Oct

55.7b

19.8e

4.6fg

3.9e

4.7f

10.9c

0.0c

99.6

1st Nov

17.1e

2.7f

10.1de

14.3d

0.0f

0.0e

0.0c

44.2

50%

1st Oct

84.1a

53.1ab

52.1a

22.2c

25.3b

31.1a

25.7a

293.6

15th Oct

37.0d

29.6d

14.7c

21.6c

14.7de

13.3b

0.0c

130.9

1st Nov

21.2e

5.8f

14.6c

6.5e

41.3a

0.0e

0.0c

89.4

0% (bare)

1st Oct

56.8b

56.5a

28.9b

12.5d

4.7f

9.5cd

3.7b

172.6

15th Oct

55.2b

49.2bc

9.9de

0.0f

11.7e

10.9c

2.7b

139.6

1st Nov

47.3c

44.9c

1.4gh

26.6b

17.8cd

10.6c

4.4b

153.0

0% (burnt)

1st Oct

53.1b

1.3f

17.2c

0.0f

12.3de

11.5bc

0.0c

95.4

15th Oct

0.0f

2.8f

6.6ef

4.1e

21.2bc

0.0e

0.0c

34.7

1st Nov

3.9f

6.5f

0.0h

33.7a

0.0f

0.0e

0.0c

44.1

Means

42.9±1.9

24.2±2

14.5±1.4

12.7±1.1

13.1±1.9

8.8±0.77

3 ± 0.78

119.7
4.7. Agroforestry Research in GRD
Research on adoption of agroforestry innovations is critical because during the past decades it has become clear that there is a gap between advances in agroforestry science and the success of agroforestry-based development programs and projects
[19]
. It is fundamental to understand how and why farmers make long-term land-use decisions because this knowledge should be applied when developing, designing and “marketing” agroforestry innovations. Many research works were done by the gum arabic researchers in North Kordofan and South Darfur Sates. For example in North Kordofan Fadl and El sheikh 2004/05 and 2005/06 studied the effect of Acacia senegal agroforestry system on growth and yield of groundnut (Arachis hypogea), sesame (Sesamun indicum) and roselle (Hibiscus sabdariffa). The results indicated that intercropping reduced groundnut yield by 26%, sesame by 21% and roselle by 20%. Gum yield at Eldamokeya was significantly (P≤ 0.05) under groundnut, sesame and roselle intercropping system (Table 9). The yield per tree was computed per ha (375 trees per ha). In all pickings, the average yield ranged between 12 and 40 g/picking/tree. In the first season, the highest production per tree for the four pickings (124g) was obtained in pure stand of A. senegal, followed by intercropped roselle (108g) intercropped groundnut (97g) and intercropped sesame (89g). in the second season (2005), the higher yield (122g) was obtained in sole A. senegal followed by roselle intercropped (113g), groundnut intercropped (106g) and intercropped sesame (92g). The effect of cropping season on gum yield (g/tree) was not significantly different (P≤ 0.05). All the treatments gave LER of more than one—indicating the superiority of growing the field crops in intercropping over the sole cropping systems. The highest LER of (1.71) was obtained when roselle was intercropped with A. senegal, while the lowest LER (1.48) was obtained when groundnuts were intercropped with A. senegal (Table 10). All the treatments gave positive net revenues, the highest being for intercropped roselle (438 SDG/ha). The intercropping of sesame gave the second highest net revenue (387 SDG/ha), while the sole roselle gave the lowest net revenue (97 SDG/ha) (Table 11). They concluded that Agroforestry systems including A. senegal provide a good household income from gum Arabic production which can easily compensate for other crop yield losses
[13]
. Systems combining A. senegal and crops such as groundnuts, sesame and roselle have a useful role to play in sustaining agriculture and providing revenues in the arid areas of North Kordofan. From land use efficiency, productivity and profitability point of view.
The GRD 2010 and 2011 carried out an assessment to the agroforestry systems in North and South Kordofan States with objectives to identify and assess the most important agroforestry systems, to characterize major tree species in different agroforestry system, to prioritize major constraints on agroforestry systems in the region, and to study the current status of gum arabic trees and their contribution on farmers livelihood
[24]
. They concluded that in the traditional rainfed area of Kordofan region and with increasing rate of desertification and natural resources degradation managing the traditional field crops with Acacia senegal and other tree species can increase productivity and crop value, and improve land use efficiency. The agroforestry systems in this area have a useful role to play in sustaining agriculture production and providing revenues in the arid areas of Kordofan region. The most important agroforestry system in the study area was found to be Acacia senegal agroforestry system Figure 6. Shifting cultivation is still practice by more than 50% of the respondents. Trees have a positive effect in restoring soil fertility and improving the microclimate.
In South Darfur, the GRD studied the effect of A. senegal re-spaced at 4 x 4, 4 x 8m, and 8 x 8m on yield of millet, sorghum and sesame intercropped with A. senegal, Moreover, to asses gum arabic yield and land Equivalent Ratio (LER). The results indicated that crops yield and straw were affected by tree spacing thus recorded higher yield under wider spacing compared with the narrow ones. LER was higher under this agroforestry system as compared to mono-cropping
[22]
. Gum arabic yield was higher in the 4 x 8m tree spacing than the other spacing Tables 9 and 10.
Table 9. Gum yield (g/tree) under different cropping system at Eldamokeya forest reserve during growing season 2004 and 2005.

Cropping systems

Pickings

Total

1

2

3

4

Season 2004

Pure Acacia senegal

35.1a

40.1a

27.1a

21.7a

124

Roselle intercropping

29.6b

36.3ab

23.5b

18.5b

107.9

Groundnut intercropping

28.0b

32.6bc

20.5c

16.0bc

97.1

Sesame intercropping

29.10b

28.5c

17.5d

13.8c

88.9

SE±

0.55**

1.18*

0.82**

0.87**

Season 2005

Pure Acacia senegal

36.8b

39.5a

26.4a

19.1a

121.8

Roselle intercropping

34.3a

36.0a

27.6a

15.6b

113.5

Groundnut intercropping

38.5a

35.0a

24.8ab

12.9c

106.2

Sesame intercropping

26.0b

29.9b

21.9b

13.9bc

91.7

SE±

0.58**

1.2*

0.48**

0.70**
Table 10. Land equivalent Ratio (LER) for the tested crops in the intercropping with A. senegal and sole cropping system.

Cropping systems

Crop yield (kg/ha)

Gum yield (kg/ha)

LER

Pure Acacia senegal

-

46

-

Sole groundnut

483.7

-

Groundnut intercropped

356.3

34

1.48

Sole sesame

346.8

-

-

Sesame intercropped

302.6

38

1.62

Sole Roselle

177.8

-

-

Roselle intercropped

140.30

42

1.71
Table 11. Partial budget for groundnut, sesame and roselle intercropped with Acacia senegal and ranked in order of increasing total production cost.

Cropping systems

Yield (kg/ha) Gross revenue Production cost Net revenue

SDG/ha

SDG/ha

SDG/ha

SDG/ha

Pure A. senegal

37

266

35

231

Sole groundnut

387

325

228

97

Groundnut intercropped

285

433

263

170

Sole sesame

278

399

184

295

Sesame intercropped

242

606

219

387

Sole Roselle

272

598

249

345

Roselle intercropped

217

722

284

438
Table 12. The effect of tree spacing on crop yield (kg/ha).

Tree spacing (m)

Millet

Season 2001

season 2002

season 2003

4x4

33.2a

13.67a

161.6b

4x8

42.0a

50.04b

553.6b

8x8

42.9a

101.0a

55582.0a

Control

37.0a

181.0a

1600.0b

LSD

26.76

27.48

2703

CV%

30.0

22.9

95.81

Sorghum

Season 2001

season 2002

season 2003

4x4

30.35b

45.8b

-

4x8

292.45a

139.97

-

8x8

440.64a

112.3 ab

-

Control

394.0a

249.0a

-

LSD

202.1

83.89

-

CV%

35.05

37.25

-

Sesame

Season 2001

season 2002

season 2003

4x4

8.75b

25.33a

161.0a

4x8

26.6 ab

48.99a

73.67a

8x8

43.41a

114.8a

181.7a

Control

66.0a

239.0a

214.0a

LSD

29.04

93.85

165.6

CV%

48.8

65.67

48.07
Means followed by the same letters are not significantly different at 5% level, - No available data (crop failure)
Source: Publication of the National Crop Husbandry Committee, Wad Medani, 2008
Table 13. Gum arabic yield (g/tree) under the sole trees and intercropping for the period 2001 to 2002.

Treatment (M)

Intercropped

Control

Intercropped

Control

Pick 1

Pick 2

Pick 1

Pick 2

Pick 1

Pick 2

Pick 1

Pick 2

4 x 4

7.5b

7.30 a

3.30 b

5.90 b

4.93 b

5.40 a

4.70 a

5.00 a

4 x 8

11.2 a

6.70 a

13.5 a

12.2 a

7.85 a

4.10 a

5.20 a

3.50 a

8 x 8

8.5 ab

8.15 a

6.20 b

5.60 b

6.0 ab

4.10 a

4.10 a

7.00 a

LSD

3.22

3.54

3.94

2.77

2.63

4.59

2.00

4.99

CV%

16.04

21.11

20.54

16.24

22.04

42.65

20.99

43.03
Means followed by the same letters are not significantly different at 5% level
Figure 6. Tree crop interaction in North Kordofan State (Photo authorized Kamal).
4.8. Provenances Trails
Despite the economical importance of the gum arabic trees, few attempts were made to select high gum yielder trees of A. senegal. In 1967 the GRD selected a seeds from the gum belt areas and planting their progenies in a progeny test in Eldamokeya Forest Reserve in western Sudan. Since 1967 till now serious research was done for and continued to be done on the selection and planting of a high yielding A. senegal trees for the rehabilitation of the degraded land of the gum arabic belt of western Sudan. Therefore, the objectives of the provenance trails is to evaluate the growth performance of A. senegal provenances at the nursery stage and under field condition to identify the provenance that has the capability to grow and yield under harsh environment and soil conditions as prevailing in the experimental site.
Two experiments were carried out by the researchers in the GRD during the growing seasons 2010\2011 and 2011\2012 in the nursery and under field conditions at El-Obeid Research Station and Eldamokey Forest Reserve. The objectives of the experiments were to study the growth performance of 15.
Acacia senegal provenances in the nursery and under field conditions to identify which provenances that capable to grow and survive under a diverse environmental conditions at Eldamokey forest reserve Tables 14 and 15. For the nursery experiment, the results showed significant differences (P≤ 0.05 and P ≤ 0.01) for shoot length, root length, number of leaves and stem diameter after two, three and for month from planting (Figure 6). At Eldamokeya Forest Reserve the results showed significant differences (P≤ 0.05 and P ≤ 0.01) for survival percentage in the two seasons and number of branches in the second season (Figure 7). The combine analysis showed significant differences for survival percentage and number of branches Table 16. Furthermore, all A. senegal provenances gave a higher survival percentage of more than 90% under the dry climatic conditions at the experimental site. The results suggested that the two provenances 2&9 are a suitable candidate for rehabilitation of Eldamokeya forest reserve and the degraded area of the gum arabic belt of western Sudan
[12]
. Most of these provenances started to yield gum Arabic but now and due to the war this experimental site is not accessible.
Table 14. Acacia senegal seed provenances tested at El-Obeid Research Station nursery and in Eldamokeya Forestry Reserve, North Kordofan State, Sudan.

Provenances Code

Provenances name

Latitudes (N)

Longitudes (E)

Altitude (m)

Soil Type

1

El Damokeya

13 16

30 29

560

Sand

2

Um Rwaba

12 52.237

31 02. 098

1565

Sand

3

El Rahad

12 46. 772

30 37. 280

1663

Sand

4

Abassyia

11° 40

31° 00

1240

Clay

5

Ambair

11 51.657

30 46. 244

1985

Clay

6

Umbrambeata

11 51.431

30 38. 77

1917

Clay

7

Habila

11 56. 412

30 01. 89

2176

Clay

8

Wasata

12° 49.29

29° 16.377

2021

Sand

9

Nabag

12 33.956

29 56. 35

1906

Sand

10

Saata

12° 46.89

29° 23.89

2009

Sand

11

Um Kreidem

13° 38. 808

29° 35. 015

2093

Sand

12

El Mazroub

13° 46.76

29° 13. 814

1972

Sand

13

Eyal Bakheet

13° 21. 886

28° 41.08

1929

Sand

14

Elnuhud

12° 39.69

28° 22.44

1831

Sand

15

El Khwai

13° 01. 343

29° 13.43

2026

Sand
Figure 7. Acacia senegal seedling at the nursery stage (Photo authorized Kamal).
Figure 8. Acacia senegal seedling after six months from field planting at Eldamokey Forest reserve (Photo authorized Kamal).
Table 15. Seed Characteristic of Acacia senegal provenances during 2010.

Provenances Code

Seed Purity%

Number of Seed\kg

Seed Moisture%

Germination%

Seed viability%

1

96.7

14665

3

66.0

94

2

97.3

15360

3

68.5

98

3

96.3

12370

5

71.0

98

4

96.7

13360

7

71.0

98

5

98.5

13640

3

79.5

92

6

98.5

13980

3

59.0

96

7

96.2

12970

3

74.0

100

8

98.7

11640

4

63.0

96

9

92.1

16750

3

44.5

96

10

97

14320

9

63.5

84

11

96.4

13350

6

74.5

98

12

98.2

13120

7

74.0

100

13

98.9

13560

5

67.0

82

14

97.7

10120

9

70.5

100

15

97.7

12340

4

65.5

96

Means

97.3

1256

4.9

67.4

94.8
Table 16. Combine analysis over season for Survival percentage, seedling height, diameter and number of branches.

Provenances Code

Survival%

Height (cm)

Diameter (mm)

No. Branches

1

95.1

34.3

0.6

4.4

2

99.2

36.8

0.5

5.2

3

97.0

31.7

0.6

5.5

4

98.2

37.9

0.6

8.6

5

98.7

35.5

0.5

5.4

6

98.7

32.2

1.2

5.1

7

97.1

32.9

0.5

4.4

8

98.2

32.5

0.6

6.0

9

99.5

32.4

0.6

7.2

10

95.4

33.0

0.7

8.4

11

95.7

35.5

0.6

10.7

12

94.3

39.3

0.6

6.8

13

95.3

33.7

0.7

7.2

14

96.7

34.9

0.6

3.5

15

95.7

34.9

0.5

5.2

Means

96.7

34.3

0.6

6.2

SE

0.81**

1.87ns

0.18ns

1.0**

CV%

20.3

15.4

43.8

45.7
5. Conclusion and Recommendation
Gum arabic yield was greatly influenced by tapping date, the gum yield (g/tree and g/picking) was significantly higher when the trees were tapped on the 1st of October and 15th of November compared with other date of tapping.
Tapping date, intensity of tapping, rainfall and maximum temperature at gum collection are the most important variable influencing gum arabic yield from Acacia senegal tree. Based on these finding it seems that gum arabic yield/production in western Sudan is less risky than agricultural crops, which face more frequent failure. However, gum Arabic yield prediction shortly before or after tapping is achievable either by knowing the commencement of tapping or by knowing yield of the first picking.
The gum yield of Acacia senegal increase due to tapping in the Eastern and Western Sides of the branches towards direct sun light. Similarly, the number of yielded trees was higher for those tapped in the East and West sides compared to trees tapped in the Northern and Southern sides.
Gum arabic yield was significantly increased by increase in density of grasses and the date of tapping was proved to have significant effect on gum yield. The early tapping gave more gum yield compared with the other dates of tapping. Furthermore, the density of grasses and the date of tapping have a significant effect on number of gum pickings.
Agroforestry systems including A. senegal provide a good household income from gum Arabic production which can easily compensate for other crop yield losses. Systems combining A. senegal and crops such as groundnuts, sesame and roselle have a useful role to play in sustaining agriculture and providing revenues in the arid areas of North Kordofan. From land use efficiency, productivity and profitability point of view.
Based on the above mentioned finding the following recommendation can be made:
1) The optimum tapping date of plantation and managed natural stands of Acacia senegal is 1 October to 15 October.
2) Gum gardens and natural farm stands of Acacia senegal should be tapped in 1 October to 1 November.
3) Gum arabic yield of a coming season is predictable using a prescribed plan of tapping in term of time and intensity and using temperature forecasts.
4) The early tapping gave more gum yield compared with the other dates of tapping. Furthermore, the density of grasses and the date of tapping have a significant effect on number of gum pickings.
5) To increase gum arabic production in South Kordofan it is recommended to tap the tree during the period from 15 October to 1 November.
6) From and economical point of view, it is recommended that roselle and sesame can be intercropped with A. senegal.
Abbreviations

GRD

Gum Arabic Research Division

LER

Land Equivalent Ratio

FNC

Forest National Corporation

ARC

Agricultural Research Corporation

WARAP

Western Sudan Agricultural Research Project
Conflicts of Interest
The authors declare no conflicts of interest.
References
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[20] Muneer Elyas Siddig Eltahir, Kamal Eldin Mohamed Fadl, Mohammed Adam Abbas Hamad, Ahmed Ismail Ahmed Safi, Hatim Mohamed, Ahmed Elamin, Yahia Ibrahim Mohammed Abutaba, Faisal Ismail Musa, Tarig Elsheikh Mahmoud, Asmamaw Alemeu, Hamdon AliAbdelrhman, Osman Elsaid Adlan, Salih Omer Tutu, Mohammed Hamed Mohammed, Yahia Omer Adam Gumaa, Awadelkareem SulimanOsman Khalifa, Abdalaziz Elsaid Hamad, Seif Aldin Dawina Abdallah Faragallah, Mohammed Osman Hassan, Medani Ismaeil, Heba Abdalla Noureldeen, Alsammani Ali Mohammed, Elsayed Mohamed Elmustafa Osman, Mohamed Elnour Taha, Manal Awad Kheiry (2023). Tapping Tools for Gum Arabic and Resins Production: A review Paper. American Journal of Engineering and TechnologyManagement. Vol. 8, No. 3, 2023, pp. 33-40.

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[21] NAS. 1979. Fire wood crops: shrubs and tree species for energy production. Volume 1 and 2. Washington, DC: National Academy Press. pp 329.
[22] Nasereldin, M, Abdalla, Husein, S, Godan and Raddad, Elamin, Y (2008). Agroforestry for sustainable dry land farming in Southern Darfur. Proceedings of the 43th meetings of the Nation Crop Husbandry Committee, Wad Medani, 2008.
[23] Obeid, M. and Sef Eldin, A, (1970). Ecological studies of the Vegetation of the Sudan Acacia Senegal (L.) Willd and its natural regeneration, Journal of Applied Ecology, 7: 507-518.
[24] Oleghe, P. E, and Akinnifesi, F, K (1992). Nitrogen Fixing Trees. Research Reports Vol. 10.
[25] Ross JH. 1979. A conspectus of the African Acacia Species. Memoirs of the Botanical Survey of South Africa, No. 44.
[26] Sayeda, A. A. Khalil, H. A. El Atta and I. M. Aref (2011). Increased gum arabic production after infestation of Acacia senegal with Aspergillus flavus and Pseudomonas pseudoalcaligenes transmitted by Agrilus nubeculosus. African Journal of Biotechnology Vol. 10(37), pp. 7166-7173, 20 July, 2011.
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    Fadul, K. E. M., Eltahir, M. E. S., Adam, I. M., Ali, A. H., Elkhidir, H. A., et al. (2025). Gum Arabic Research in Sudan During the Period 2000-2025 a Review Paper for Some of Research Activities During the Period 2000-2025. American Journal of Agriculture and Forestry, 13(3), 152-168. https://doi.org/10.11648/j.ajaf.20251303.12

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    Fadul, K. E. M.; Eltahir, M. E. S.; Adam, I. M.; Ali, A. H.; Elkhidir, H. A., et al. Gum Arabic Research in Sudan During the Period 2000-2025 a Review Paper for Some of Research Activities During the Period 2000-2025. Am. J. Agric. For. 2025, 13(3), 152-168. doi: 10.11648/j.ajaf.20251303.12

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    Fadul KEM, Eltahir MES, Adam IM, Ali AH, Elkhidir HA, et al. Gum Arabic Research in Sudan During the Period 2000-2025 a Review Paper for Some of Research Activities During the Period 2000-2025. Am J Agric For. 2025;13(3):152-168. doi: 10.11648/j.ajaf.20251303.12

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  • @article{10.11648/j.ajaf.20251303.12,
  author = {Kamal Eldin Mohammed Fadul and Muneer Elyas Siddig Eltahir and Idris Musa Adam and Abbas Hassan Ali and Hatim Abdalla Elkhidir and Mustaffa Abdalla Nasreldin and Sona Mohammed Fadual and Mohammed Mukhtar Ballal},
  title = {Gum Arabic Research in Sudan During the Period 2000-2025 a Review Paper for Some of Research Activities During the Period 2000-2025
},
  journal = {American Journal of Agriculture and Forestry},
  volume = {13},
  number = {3},
  pages = {152-168},
  doi = {10.11648/j.ajaf.20251303.12},
  url = {https://doi.org/10.11648/j.ajaf.20251303.12},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajaf.20251303.12},
  abstract = {This paper is an attempt to review some of the research work that was carried out by the Gum Arabic Research Division (GRD) during the period 2000 to 2025. The objectives is to give a highlight about the research finding that provided by the Gum Arabic Research Division and to disseminate these finding to the gum producers, stakeholders such as companies, forest administrations, producers association and the other relevant research institutes. During the period 2000-2025 many research excrement’s were carried out by the gum arabic research scientist at El-Obeid, Kadugli and Nyala Research Stations. These experiments include tapping tools, date of tapping, tapping intensity, position of tapping (branch, lower stem, middle stem, and higher stem), tapping direction, the relationship between climatic factors, tapping and gum arabic yield, provenances trails and agroforestry trails. For tapping tools, the Sonki (new innovative tool developed by GRD) is found as a best tool for tapping Acacia senegal trees. It is reported that it has muti-function where it could be used for tapping the tree and harvesting the gum. The GRD was found that gum arabic yield was greatly influenced by tapping date, the gum yield (g/tree and g/picking) was higher when the trees were tapped on the 15th of October and 1st of November compared with other date of tapping. The GRD found that gum arabic yield prediction shortly before or after tapping is a achievable either by knowing the commencement of tapping or by knowing yield of the first picking. For the effect of tapping in various azimuth angles on gum arabic yield we found that gum yield of Acacia senegal increase by 67.6 and up to two folds as due to tapping in the Eastern and Western Sides of the branches towards direct sun light. 15 Acacia senegal provenances were examined in the nursery and under field conditions to identify which provenances that capable to grow and survive under a diverse environmental conditions at Eldamokey forest reserve. All A. senegal provenances gave a higher survival percentage of more than 90% under the dry climatic conditions at the experimental site. For agroforestry research it was found that intercropping of of Acacia senegal with groundnut, sesame and roselle provide a good household income from gum arabic production which can easily compensate for other crop yield losses. For tree spacing the finding from GRD indicated that crops yield and straw were affected by tree spacing thus recorded higher yield under wider spacing compared with the narrow ones. LER was higher under agroforestry system as compared to mono-cropping. The study concluded that gum arabic yield was greatly influenced by tapping date and tapping intensity. The gum yield of Acacia senegal increase due to tapping in the Eastern and Western Sides of the branches towards direct sun light. From and economical point of view, it is recommended that roselle and sesame can be intercropped with A. senegal.},
 year = {2025}
}

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  • TY  - JOUR
T1  - Gum Arabic Research in Sudan During the Period 2000-2025 a Review Paper for Some of Research Activities During the Period 2000-2025

AU  - Kamal Eldin Mohammed Fadul
AU  - Muneer Elyas Siddig Eltahir
AU  - Idris Musa Adam
AU  - Abbas Hassan Ali
AU  - Hatim Abdalla Elkhidir
AU  - Mustaffa Abdalla Nasreldin
AU  - Sona Mohammed Fadual
AU  - Mohammed Mukhtar Ballal
Y1  - 2025/07/19
PY  - 2025
N1  - https://doi.org/10.11648/j.ajaf.20251303.12
DO  - 10.11648/j.ajaf.20251303.12
T2  - American Journal of Agriculture and Forestry
JF  - American Journal of Agriculture and Forestry
JO  - American Journal of Agriculture and Forestry
SP  - 152
EP  - 168
PB  - Science Publishing Group
SN  - 2330-8591
UR  - https://doi.org/10.11648/j.ajaf.20251303.12
AB  - This paper is an attempt to review some of the research work that was carried out by the Gum Arabic Research Division (GRD) during the period 2000 to 2025. The objectives is to give a highlight about the research finding that provided by the Gum Arabic Research Division and to disseminate these finding to the gum producers, stakeholders such as companies, forest administrations, producers association and the other relevant research institutes. During the period 2000-2025 many research excrement’s were carried out by the gum arabic research scientist at El-Obeid, Kadugli and Nyala Research Stations. These experiments include tapping tools, date of tapping, tapping intensity, position of tapping (branch, lower stem, middle stem, and higher stem), tapping direction, the relationship between climatic factors, tapping and gum arabic yield, provenances trails and agroforestry trails. For tapping tools, the Sonki (new innovative tool developed by GRD) is found as a best tool for tapping Acacia senegal trees. It is reported that it has muti-function where it could be used for tapping the tree and harvesting the gum. The GRD was found that gum arabic yield was greatly influenced by tapping date, the gum yield (g/tree and g/picking) was higher when the trees were tapped on the 15th of October and 1st of November compared with other date of tapping. The GRD found that gum arabic yield prediction shortly before or after tapping is a achievable either by knowing the commencement of tapping or by knowing yield of the first picking. For the effect of tapping in various azimuth angles on gum arabic yield we found that gum yield of Acacia senegal increase by 67.6 and up to two folds as due to tapping in the Eastern and Western Sides of the branches towards direct sun light. 15 Acacia senegal provenances were examined in the nursery and under field conditions to identify which provenances that capable to grow and survive under a diverse environmental conditions at Eldamokey forest reserve. All A. senegal provenances gave a higher survival percentage of more than 90% under the dry climatic conditions at the experimental site. For agroforestry research it was found that intercropping of of Acacia senegal with groundnut, sesame and roselle provide a good household income from gum arabic production which can easily compensate for other crop yield losses. For tree spacing the finding from GRD indicated that crops yield and straw were affected by tree spacing thus recorded higher yield under wider spacing compared with the narrow ones. LER was higher under agroforestry system as compared to mono-cropping. The study concluded that gum arabic yield was greatly influenced by tapping date and tapping intensity. The gum yield of Acacia senegal increase due to tapping in the Eastern and Western Sides of the branches towards direct sun light. From and economical point of view, it is recommended that roselle and sesame can be intercropped with A. senegal.
VL  - 13
IS  - 3
ER  -

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  • Abstract
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  • Document Sections

    1. 1. Introduction
    2. 2. Gum Arabic Research Division (GAD)
    3. 3. Previous Research Work
    4. 4. Recent Research Finding
    5. 5. Conclusion and Recommendation
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