Ethnobotany of medicinal plants
The people in the study area use diverse plant species for traditional medicinal purpose to treat both human and livestock ailments. The results of the ethnobotanical study revealed that 81 medicinal plant species distributed in 77 genera belonging to 48 different families were frequently used for the treatment of various ailments in the study sites. Of the total plant species, eight that are endemic to Ethiopia were being used by the local people in their traditional medical lore (Appendix 1 and Appendix 2).
Of the total collected MPs, 68 plant species were used for the treatment of human ailments and 24 species were used against livestock diseases and 10 common plants species were listed in both cases which used to treat both livestock and human ailments. In the study site, large numbers of MPs were used to treat human ailments than livestock ailments (Appendix 1 and Appendix 2). According to the informants, the other possible reason is female informants were fewer than males. This is because livestock production is usually a cultural care for males. As a result, there could be acquiring low knowledge of MPs to treat livestock ailments than knowledge of MPs treating human ailments. Similar ethnobotanical findings were reported in [17].
Different families of MPs were recorded. Among them Asteraceae is the most dominant family that held 9 (11.11%) plant species followed by Solanaceae 6 (7.41%) species and Lamiaceae 5 (6.17%) species. Other taxa commonly used were Cucurbitaceae having 4 (4.94%) species, and Euphorbiaceae and Fabaceae (each 3 species, 3.70%). The remaining forty two (42) families hold fifty one plant species. Of which nine of them account two species. The rest of the families signify one species (Figure 3). The domination of medicinal plant species families mentioned above may possibly be attributed to their wider distribution and abundance in the flora area [28]. This is also further confirmed by regular recording of ethnomedicinal uses of species from the above mentioned families in different other Ethiopian ethnobotanical studies [15, 16, 29]
Habits of medicinal plants which treat diseases
The finding indicated that the most widely used MPs growth form in the different Kebeles of the study areas were herbs 33 (41%) followed by shrubs 27 (33%). Trees and climbers account 14 (17%) and 7 (9%) respectively (Figure 4). This study confirmed that herbs are the largest in number this may be due to the plant species exhibit high level of abundance and easy to access them. This finding agreed with the findings of other indigenous researchers [30, 16].
Medicinal plants in natural habitat and home-gardens
Most MPs were collected in their natural habitat (Chemoga forest patch) which account for 51 (67%) whereas, 18 (22%) of them from home-garden and nine (11%) from both home-garden and wild (Figure 5). Similarly, various studies conducted in Ethiopia reported as majority of MPs harvested from wild [16-18] Here, the findings revealed that relatively many MPs were also obtained from home-gardens. This indicated that the people and the local healers have started cultivating MPs in their gardens. Similar results were reported in[ 8].
Plant parts used in medicine preparation
Every part of different plant species are used against a variety of ailments. As per the informant’s response, the most commonly used part is the leaf (29), followed by root (16), seed (11), fruit (7), stem (3), flower, leaf and stem, and bark (2, each) (Figure 6; Appendix 1 and Appendix 2 ). In some cases, more than one organ of the same plant species, particularly a combination of parts, are used in the preparation of different therapies.
Traditional method and condition in remedy preparations
The popular method of preparation of traditional medicine was crushing and squeezing account 37 (34%) followed by powdering (powder form) 26 (24%). It was also recorded that 15 (14%) were prepared in juice form, 8 (7%) - chewing form, and 7 (6%) in the form of fumigation and boiling (each), 4 (4%) immersion. Other methods such as paste form, raw form and the like accounted 5 (5%) (Figure 7). Methods can be used for human and livestock problem except chewing which is used only for humans.
The result in the conditions of plant part used indicated that most medicines about 71% of traditional MPs were prepared from fresh plant materials in the study site whereas 26% and 3% MPs were reported to be used dry and both in dry or fresh form respectively (Figure 8; Appendices, 1 & 2). The common usage of fresh material was also noted in other parts of the country in [31, 17, 18, & 29].
Routes of administration
Oral application was the most commonly used route of administration accounting for 70 (59.8%), followed by dermal (31 preparations, 26.49%) and nasal (11 preparations, 9.40%), Nasl/oral (4 preparations, 3.42%) and anal (1 preparation, 0.9%) (Figure 9; Appendix 1 and Appendix 2). Similar route of administration was also reported by [17,29].
Dosage
Traditional healers reported to estimate dosages using mankia (lid spoons), woket (handfuls) (for powder preparations) sini (cup), tassa’ (can) and birchiko (glass) (for liquid mixtures to be administered) for medicinal preparations. Furthermore some other healers reported that numbers or in some cases handfuls (for leaf, seed and fruits) and atik (tip of finger) (for roots, stems or barks) were used. The measurements used to determine the dosages are not standardized and depend on the age, physical appearance of the patient, degree of the illness, diagnosis and experience of individual herbalists/or knowledgeable person. Additional study confirmed that children are given less than adults, such as, one fourth of a coffee cup whereas; an adult is given up to one glass depending on the type of illness and treatment[12].
Fidelity Level
Fidelity levels were calculated for Plumbago zeylanica and Prunus africana; having highest scores (100%) each which treated diseases like wounds followed by Solanum adoens (90) treated eczema. On the other hand, Rhamnus prinoides which treated tonsillitis, skin infection and dysentery had the least score (50%) (Table 1). Plants that are known as remedies of a single ailment have 100% FL as compared to those that are used as remedies for more than one type of aliment. Most of the plants with high FL values have pharmacological effects that have been proven scientifically. The lowest ones indicated less preferred species for treating specific ailments. In contrast, these plants have been widely used against several diseases. Plants with the highest fidelity level values could be targeted for further photochemical investigation to prove the bioactive components that are responsible for their high healing potential [32]
Table 1 Fidelity level values of medicinal plants commonly reported against given ailments
Plant species
|
Diseases treated
|
Ip
|
Iu
|
FL values (%)
|
Plumbago zeylanica
|
Wounds
|
7
|
7
|
100.00
|
Prunus africana
|
Wounds
|
8
|
8
|
100.00
|
Solanum adoense
|
Eczema
|
10
|
10
|
90.00
|
Verbena officinalis
|
Stomachache & intestinal parasite
|
12
|
15
|
80.00
|
Rumex nepalensis
|
Blood pressure and stomachache
|
18
|
24
|
75.00
|
Brucea antidisenterica
|
Diarrhea, wound and leschmaniasis
|
15
|
20
|
75.00
|
Laggera tomentosa
|
Common cold and toothache
|
25
|
35
|
71.42
|
Carica papaya
|
Gastritis, malaria and diarrhea
|
25
|
45
|
55.56
|
Rhamnus prinoides
|
Tonsillitis, skin infection and dysentery
|
20
|
40
|
50.00
|
Key: FL= Fidelity Level, Ip = Number of informants who independently cited the importance of a species for treating a particular disease, Iu = Total no of informants who reported the plant for any given disease.
Preference ranking
If a number of species are prescribed for the same ailment, people will tend to show preference of one over the other. Thus, preference ranking of six MPs which were reported against leech (livestock disease) was conducted after selecting six key informants. The informants were asked to compare the given MPs based on their efficacy, and to give the highest number (5) for the medicinal plant which they thought most effective against leech and the lowest number (1) for the least effective plant in treating the disease. The results showed that Nicotiana tabacum was the most preferred followed by Rhamnus prinoides and Solanum marginatum (See Table 2). Result of the preference ranking exercise also indicated that N. tabacum is the most-preferred ethno veterinary MPs used to treat leech. This may be attributed to the occurrence of bioactive compounds against leech in this species.
Table 2 Preference ranking of medicinal plants against leech in livestock
Medicinal Plants
|
Respondents (R1-R6)
|
Total
|
Rank
|
R1
|
R2
|
R3
|
R4
|
R5
|
R6
|
Nicotiana tabacum
|
4
|
4
|
3
|
4
|
5
|
5
|
25
|
1st
|
Rhamnus prinoides
|
4
|
4
|
3
|
4
|
4
|
4
|
23
|
2nd
|
Solanum marginatum
|
4
|
4
|
3
|
4
|
4
|
4
|
23
|
3rd
|
Otostegia integrifolia
|
1
|
4
|
3
|
3
|
3
|
2
|
16
|
4th
|
Lagenaria abyssinica
|
3
|
2
|
2
|
3
|
2
|
2
|
14
|
5th
|
Guizotia abyssinica
|
3
|
2
|
2
|
2
|
2
|
1
|
12
|
6th
|
Paired comparison
In this study, seven key informants made the pair wise comparisons of five MPs and the values were summarized as follow. It was found that Acmella caulirhiza species stood first followed by Laggera tomentosa for the treatment of toothache. Olea europaea subsp. cuspidata, Solanum marginatum and Momordica foetida were placed 3rd, 4th and 5th respectively (Table 3).This rank is because of the effectiveness of the plant in the point of view of the indigenous people of the study areas.
Table 3 Paired comparison of medicinal plants used to treat toothache.
Medicinal Plants
|
Respondents (R1-R7)
|
Total
|
Rank
|
R1
|
R2
|
R3
|
R4
|
R5
|
R6
|
R7
|
Acmella caulirhiza
|
3
|
4
|
4
|
4
|
3
|
5
|
3
|
24
|
1st
|
Laggera tomentosa
|
3
|
4
|
3
|
3
|
3
|
3
|
4
|
23
|
2nd
|
Olea europaea subsp. cuspidata
|
2
|
3
|
3
|
3
|
3
|
2
|
3
|
19
|
3rd
|
Solanum marginatum
|
3
|
2
|
2
|
3
|
2
|
2
|
2
|
16
|
4th
|
Momordica foetida
|
1
|
2
|
2
|
2
|
3
|
2
|
2
|
14
|
5th
|
Direct matrix ranking
Many MPs were found to be used for different purposes in addition to their medicinal values. The major uses include firewood, furniture, forage, charcoal, and edible. For ranking seven key informants were asked to give value, 5 to the most used plant for that particular purpose and 0 to the least. In view of that, Cordia affricana was found to be the most multi-purposed plant scoring 93, followed by Carissa spinarum scoring 87 and the least one was Croton macrostachyus having 72 scores (Table 4). The highest direct matrix ranking on the topic of C. africana was also reported in [33]. This confirms that as the value getting high, the plants have multiple uses in the context of the local community.
Table 4 Direct matrix ranking for the multipurpose of six medicinal plants.
Medicinal plants
|
Use Categories
|
Total
|
Rank
|
Medicine
|
Fire-wood
|
Furniture
|
Forage
|
Soil con.
|
Edible
|
Cordia africana
|
24
|
20
|
24
|
5
|
10
|
10
|
93
|
1st
|
Carissa spinarum
|
27
|
17
|
5
|
10
|
12
|
16
|
87
|
2nd
|
Prunus africana
|
20
|
21
|
20
|
5
|
8
|
8
|
82
|
3rd
|
Olea europaea subsp. cuspidata
|
20
|
22
|
14
|
5
|
9
|
5
|
75
|
4th
|
Vernonia amygdalina
|
30
|
20
|
15
|
0
|
8
|
0
|
73
|
5th
|
Croton macrostachyus
|
29
|
19
|
18
|
0
|
6
|
0
|
72
|
6th
|
Characteristics of the informants
The informants were local inhabitants aged between 25–85 years (Table 5). Most of traditional healers range within the age group of 46-85 years, 76 (47.5%). These are followed by those who are around 30-45 years of age, 44 (27.5%) who also constitute a reasonable number, thus in most cases these are newly inaugurated traditional healers. The remaining 40 (25%) of informants were between the ages of 25-29 (Table 4). They are within this range because it is at this stage whereby they have completed necessary rites of passage, notably initiation school. With regards to sex, 100 (62.5%) of the total informants were males whereas, the remaining with 60 (37.5%) were reported as females. In terms of numbers, females are small in number. In the case of knowledge difference between the two sexes, females tend to mention little number of MPs as compared to males (Table 4). The educational rank of the informants exemplified that most of them were literate i.e. having modern education (diploma holders, students and those who able to read and write) which accounted for 66 (41%) followed by those who are uneducated ones but conventionally knowledgeable informants accounted with 54 (34%) and the least number of respondents were reported as church education attendants with 40 (25%). Concerning to the marital status of the informants, majority of them were married people which accounted for 42 (52.5%) followed by the unmarried ones 32 (40%) and others were divorce which was reported as six (7.5%).
Indigenous traditional plant knowledge transfer
The most important way of transfer of IK on types of use of MPs, mode of preparations, way of administration, traditional idea of illnesses, methods of diagnosis and treatment among indigenous herbal practitioners of the community was by word of mouth to a family member.
The selection of the elect was based upon his/her good conduct and ability to keep the secret with regards to the ethnobotanical plant use knowledge. Furthermore it was reported that at family level, it is restricted to the elders (men and women), followed by elder son or daughter or their trustworthy person when the mother or the father is getting old or near to die as in Ankober District [16] and Farta District [29].
Table 5 Socio-demography of the informants in the study area.
Informants
|
Categories
|
No.
|
%
|
Sex
|
Male
|
100
|
62.50
|
Female
|
60
|
37.50
|
Total
|
160
|
100
|
Age
|
25-29 years
|
40
|
25.00
|
30-45 years
|
44
|
27.50
|
46-85 years
|
76
|
47.50
|
Total
|
160
|
100
|
Marital Status
|
Married
|
Male
|
54
|
33.75
|
Female
|
30
|
18.75
|
Total
|
84
|
52.50
|
Single
|
Male
|
40
|
25.00
|
Female
|
24
|
15.00
|
Total
|
64
|
40.00
|
Divorce
|
Male
|
8
|
5.00
|
Female
|
4
|
2.50
|
Total
|
12
|
7.50
|
Grand total
|
160
|
100
|
Educational Status
|
Modern education
|
66
|
41.00
|
Church education
|
40
|
25.00
|
Illiterate
|
54
|
34.00
|
Total
|
160
|
100
|
Threats, conservation and management practices of IK associated with MPs
The data collected through both group and individual discussions with key informants indicated that the most mentioned threats to medicinal plants of the study area were overgrazing 29 (19.4%) firewood collection 28 (18.80%), agricultural expansion 26 (17.44%), charcoal making 24 (16.11%), construction 22 (11.68%) and fencing 20 (13.42%) (Table 6) hence have effects in threatening the medicinal plants and associated IK of the study community. Findings of [17] indicated that intense deforestation became the major threat on MPs in their respective study sites. Others [30] reported agricultural expansion as the major factors contributing to the local decline medicinal plants.
In the study area, threats which erode IK were caused by secrecy, oral based knowledge transfer, and unwillingness of young to gain the knowledge, influence of modern education and awareness factors. Group discussion confirmed that the knowledge of the local community especially the young age group has diminished from time to time. According to [ 29] the immediate and serious threat to the local medical practice and transfer in Ethiopia arise from the increasing influence of modernization such as increase of modern education; industrialization; changes in life style and migration from rural to urban areas.
In the study site, irregular remnants of aged dry afromontane evergreen forests mainly around the Ethiopian Orthodox Tewahido Churches, unreachable areas and Monastery are contributing much a lot to the conservation of MPs. According to the informants, in most cases attempts regarding to conservation was weak. However, very few management practices were carried out in the home-gardens in and around Chemoga forest patch by the indigenous people. Few traditional healers in the study area have brought the different curative plants and other cultivated plants from different corners and started to conserve the plants in the home-gardens. The plants under this category were Allium sativum, Artemisia abyssinica, Foeniculum, vulgare, Lippia adoensis, Nicotiana tabaccum, Ocimum lamiifolium, Ruta chalepensis, Rhamnus prinoides and Verbena officinalis. Management practices like intercropping and crop rotation were also observed among very few farmers of the study area. In so doing, herbal remedies are continued to exist because of the existence of other plant species.
Table 6 Ranking of threats on medicinal plants (values 1-5: 1= the least destructive and 5 = the most destructive)
Threats
|
Respondents (A-G)
|
Total
|
%
|
Rank
|
A
|
B
|
C
|
D
|
E
|
F
|
G
|
Overgrazing
|
5
|
4
|
4
|
3
|
4
|
4
|
5
|
29
|
19.46
|
1st
|
Fire wood collection
|
4
|
4
|
5
|
4
|
3
|
3
|
5
|
28
|
18.80
|
2nd
|
Agricultural expansion
|
3
|
3
|
4
|
3
|
4
|
5
|
4
|
26
|
17.44
|
3rd
|
Charcoal making
|
4
|
4
|
3
|
4
|
2
|
3
|
4
|
24
|
16.11
|
4th
|
Construction
|
3
|
2
|
3
|
4
|
3
|
4
|
3
|
22
|
14.77
|
5th
|
Fencing
|
4
|
3
|
3
|
2
|
2
|
3
|
3
|
20
|
13.42
|
6th
|