Plant Biology and Biodiversity Management

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Abundance and Diversity of Top Soil Earthworms in Relation to Chemical Use in Golden Rose Agrofarm, Tefki Area, Ethiopia
(Addis Ababa University, 2007-07) Mergia, Addisu; Mengistou, Seyoum (PhD)
Despite the current environmental controversies, flower farms are becoming hot areas of investment in Ethiopia. Golden Rose Agro Farm is one of the largest, and the pioneer, flower industries in the country. To study the abundance and distribution of top soil earthworms in relation to chemical use in the farm, a total of 208 1mx1 m quadrates were marked on the ground in 10 randomly selected greenhouses. Similarly, 208 quadrates were marked in the outside chemical-free farm for comparison. Soil was then dug to a depth of 15 cm in all of the marked quadrates and hand-sorted to collect top soil earthworms. Eight plastic buckets, each filled with soil at 15 cm depth, were taken and 15 adult worms originally from chemical-free soil were introduced in to each and all were put in the greenhouses, some under chemical treatment and some free for comparison. Worms from the rose farm were also transferred to chemicalfree soil and changes were observed after 20 days. Earthworms were taxonomically identified to genus level using taxonomic keys. There was strong statistically significant variation in abundance of both adult and juvenile top soil earthworms between the two farms (P < 0.01, α=0.05). Out of the 75 adult worms introduced into the chemical-treated buckets, 98.7% (74) were dead, and in the Chemical-free buckets, out of the 45 worms originally introduced, about 95.6% (38 adult and 5 juveniles) were recaptured. About four genera of earthworms were identified in the study area, but majority of them belong to the genus Eiseniella and Dendrobaena. Seasonal variation in number and distribution of earthworms was also observed in the study. Chemical use in Golden Rose Agrofarm strongly affected abundance and distribution of top soil earthworms in the area
Agro-Morphological, Physiological and Yield Related Performances of Finger Millet [Eleusine coracana (L.) Gaertn.] (Poaceae) Accessions Evaluated for Drought Resistance under Field Condition
(Addis Ababa University, 2012-06) Assefa, Awol; Fetene, Masresha (Professor)
This study was conducted on the understanding that a comprehensive study of the impact of drought stress and screening crop accessions for drought resistance is critical in evaluating the impact of climate change and climate variability on crop production. The study was conducted in Dhera Sub center of Kulumsa Agricultural Center, Oromia Regional State, from July 10- December 13, 2011; to screen drought tolerance of 96 finger millet accessions (Eleusine coracana L. Gaertn.) for their performance under severe drought condition. Data were collected for morphological trait and physiological measurement. Significant difference (P<0.05) were recorded among accessions for selected physiological, morphological and yield related traits used for screening finger millet accessions for drought resistance. This implies there was variations among accessions collected from different agroecology for different target traits and provide opportunity to select accessions for different agroecology. (RWC), Chlorophyll Content Index (CCI) and yield related parameters, such as tillers number (TN), productive tillers (PT), seed weight per head and seed weight per plant. Based on high RWC, and CCI reading, higher root shoot ratio, green leaf number, productive tillers, ear length, ear number, grain yield per head and per plant. Based on the above parameters a total of 23 accessions were selected for their performance of drought stress tolerant and promoted to the next intensive physiological and yield evaluation. 238299, 238325, AAUFM-2, were the top three accessions which gave the highest grain yield per plant (84.5, 80 and 77.5(g), respectively. Overall this research should be further utilized for improvement of finger millet for semi-arid area of Ethiopia. Key words/phrases: Finger mille; Drought stress; Accession; Morphological & Physiological traits
Agronomic and Nutritional Qualities of Mixed Genotypes of Ethiopian Tetraploid Wheat (Triticum Durum/Turgidum and Related Species) Collections
(Addis Ababa Universty, 2017-05) Tilahun Mulugeta; Asfaw Zemede (Professor)
Ethiopian farmers have been traditionally growing several varietal mixtures in the same field that might have advantages of reducing the risks of pests and unusual environmental conditions in addition to adding variety to their diets. Replacement of farmers’ varieties with genetically uniform varieties, results in changes to crop patterns and land uses largely affecting the magnitude of the genetic diversity in Ethiopian tetraploid wheats. Therefore, this study was conducted at two locations of each Amhara, Oromia and Tigray regions with the objective of evaluating the effects of mixtures of Ethiopian tetraploid wheat collections on agronomic and nutritional quality traits and maintaining the diversity of the crop. The experiment was laid out by using alpha lattice design with three replications. The experiment had fifteen genotypes with two categories (Category one: mixtures and pure stands of Ethiopian tetraploid wheat collections and Category two: mixtures and pure stands of improved varieties). Agronomic and proximate as well as selected minerals data were taken and subjected to analysis using SAS procedures. Since genotype by location interaction was significant for agronomic traits, analysis was conducted for each locations and GGE-biplot was used to select best fit genotypes for each location. The analysis of variance showed significant differences for both agronomic and nutritional quality traits. The range of grain yield was 0.2 to 2.7tha-1 in Adet, 1.5 to 2.6tha-1 in Geregera, 0.6 to 3.0tha-1 in Debre Zeit, 2.4 to 3.4tha-1 in Chefe Donsa, 1.4 to 2.6tha-1 in Ayiba and 2.8 to 3.8tha-1 in Hagereselam. Based on the analysis of individual locations and GGE-biplot mega environment results; mixtures of top ten Amhara Region, mixtures of ten improved varieties, Assasa and Mikuye are best genotypes for Adet and Geregera of Amhara Region. Mixtures of Oromia Region, GEBRE of Oromia Region, Assasa and Mikuye are best genotypes for Debrezeit and Chefe Donsa of Oromia Region. Whereas mixtures of top ten Tigray Region, GG2 of Tigray Region, GEBRE of Oromia Region and Mangudo are best genotypes for Ayiba and Hagereselam of Tigray Region. In regarding to nutritional quality, amounts ranged from 8.1 to 13.0% for protein, 73 to 78.9%for total carbohydrate, 1.4 to 2.9% for fat, 2.5 to 3.4% for fiber, 1.1 to 3.4gm/100gm for Fe and 1.9 to 2.7gm/100gm for Zn. Significantly higher protein contents (13.0 and 11.9%) were recorded from Mangudo, mixtures of Tigray Region and TIKUR SINDE of Amhara Region. Maximum total carbohydrate (78.9%) was obtained from GEBRE of Oromia Region. Higher fat contents (2.9, 2.6 and 2.5%) were obtained from TIKUR SINDE of Amhara Region, mixtures of top ten Tigray Region and Mangudo respectively. Maximum Fe 3.4 mg/100gm and Zn (2.7 mg/100gm) were obtained from mixtures of parental lines. Therefore, it can be concluded that mixtures as well as pure lines of farmers’ varieties performed well comparatively with pure lines of high yielding improved varieties in this experiment and farmers can maintain the diversity of the crop and add supplement their diets by growing mixtures of Ethiopian tetraploid wheat genotypes. Key words: Diversity maintenance, farmers’ varieties, GGE-biplot, mega environment
Allelopathic Effects of the Invasive Prosopis juliflora (Sw.) DC. on Selected Native Plant Species at Middle Awash, Southern Afar Rift of Ethiopia.
(Addis Ababa University, 2010-01) Getachew, Samuel; Demissew, Sebsebe (Professor); Wolde, Tadessse {PhD)
The allelopathic effect of aqueous extracts of leaf, bark and root of Prosopis juliflora was studied on germination percentage, germination rate and seedling growth of Acacia nilotica, Acacia tortilis (both members of the legume Family, Fabaceae), Cenchrus cillaris and Enteropogon rupestris (both members of the grass Family, Poaceae). Effects of soil amended with decaying plant parts of P. juliflora and it’s under canopy soil were analyzed on germination percentage of the above selected plants to observe the field situation. Vegetation sampling in different habitat types in the area was made to identify the target plant species. Comparison of canopy characteristics among P. juliflora, A. nilotica and A. tortilis was also made to observe differences if any in canopy closure. P. juliflora was recorded in all habitat types in the study area: open Acacia woodland, riverine and swamp vegetation types. P. juliflora was observed invading the different habitats and affecting the plant diversity there in. Low plant diversity was recorded in P. juliflora dominated fields. Even if the canopy closure of P. juliflora was not significantly different from other trees, its growth characteristics and dense thickets formation restrict light to the ground flora and block winds. This results in the death of under canopy vegetation and hence low plant diversity. Leaf, bark and root aqueous extract of P. juliflora at 0, 0.5, 0.8, 1, 2 and 6% were prepared and their effect studied on germination percent, germination rate and seedling growth of the selected plant species in the study. Germination of A. nilotica and A. tortilis was not affected by all treatment types. Leaf and root extracts at higher concentrations inhibited germination of C. cillaris and E. rupestris. Bark extract facilitated germination of C. cillaris at lower concentrations. In general all treatment types speeded up the germination rate for A. nilotica and A. tortilis at the beginning, while these slow down the germination rate of C. cillaris and E. rupesteris. Shoot and root growth of the study species was inhibited by leaf extracts. Bark extracts were stimulatory to shoot and root growth of the species under study at lower concentrations except for C. cillaris. C. cillaris root growth was not affected by bark extracts at lower concentrations. Root extracts were stimulatory at lower concentrations while it was inhibitory at higher concentrations to shoot and root growth of the study species except for C. cillaris. C. cillaris shoot growth was not affected by root extracts at lower concentrations. Seed germination of all study species except A. nilotica was inhibited by the amended and under canopy soil. The effect was high on the grasses than on the tree species studied and root growth was more inhibited than shoot growth. Suppression of seed germination, facilitation or retardation of the germination speed and seedling growth of the study species suggests that these responses are attributed to an allelopathic effect of P. juliflora on the test species. These results indicate that the effect is species specific and leaf seems to contain greater number / amount of inhibitors than does bark and root. Bark seems to contain the least. Heavy accumulations of leaf litter under P. juliflora result in accumulation of toxic substances in soil layers, inhibiting growth of other species. This may be one of the main reasons for its invasiveness and low plant diversity seen under its canopy. Keywords: Allelopathy, aqueous extract, canopy closure, germination percentage, germination rate, habitat, plant diversity, P. juliflora, seedling growth
Allelopathy in Some Ethiopia Grasses
(Addis Ababa Universty, 1982-06) Medhanie Ghebrehiwot; Berhan Tewolde (PhD)
Investigation for possible chemical interactions among some of the common grass species that grow in and around Addis Ababa was undertaken. The species used were the grasses Alldropogon abyssinicus R. Br. ex Fl:·esen, Hyparrhenia arrhenobasis (Hochst. ex. Steud.) Stapf, Pennisetum glabrum Steud., SnOl"ldenia polystachya (Fre san) Pi Ige1', E leusine jaegeri Pi Iger, &ragrosti8 tenuifolia (A. Rich) Steud. and a legume, ~!edicago polymorpha L. The effects of the extracts of the seven species on the seed germination and plumule and radicle growt'h of the same seven species shoW}d that ~. abyssinicus and ~. polystaohya were the most inhibitory followed by H. arrhenobasis and .!!!... jaegeri in that order. Extracts from!!!... tenuifolia, H. polymorpha and P. glabrum showed less inhibitory effects than the above species. See.d germination inhibition effect Was greatest on ~. polystachya and P. glabrum and that on E. jaegeri and H. arrhenobaaia '"aa the least. Auto-inhibition ,"as found to be as high as allo-inhibition. Extracts from all the species except!!!... tenuifolia ShO\fed auto-inhibitory effecta on germination and plumule growth and/or radicle grovlth. Different experiments Vlere carried out to detect the \fay of release of the inhibitory chemical(s) in ~. abyssinious. The results obtained from these experiments indicate that !. abyssinicus inhibits other speoies when decomposition of its dead .remains takes place and that the live plant doss not re lease any alle lopathic st'bstance into the soil medium
Amoebic and Giardia Infections Among Diarrhoeal Patients in Lideta Health Center, Addis Ababa, Ethiopia
(Addis Ababa University, 2018-08-04) Getachew, Abiyot; Adamu, Haileeyesus (PhD)
Amoebic and giardia infections are one of the major public health problems in many countries including Ethiopia. They are more common in children due to poor personal hygiene and lack of awareness. The objective of the present study was to identify intestinal protozoan parasite species and to determine their prevalence among patients visiting Lideta health center, Addis Ababa, Ethiopia. The design of the study was a crosssectional parasitological survey involving examination of fresh stool drawn from patients visiting the health center, during September 2017- May 2018. Data were gathered by means of questionnaire survey and laboratory parasitological examination procedures. The stool samples were examined using direct wet-mount and formol-ether concentration methods. From the total of 240 study participants, 122(50.8%) were males and 118(49.2%) females. In the study 27(22.1%), 17(13.9%) males and 23(19.5%), 20(16.6%) females were positive for Entamoeba histolytica /dispar/ moshkoviskii and Giardia lamblia respectively. The overall prevalence of amoebic and giardia infections was 36.3 %. The prevalence of amoebic and giardia infections was significantly associated with some risk factors such as habit of eating uncooked vegetables and unwashed fruits (p= 0.014), unhygienic toilet (p= 0.042), hand washing before meal or after toilet (p= 0.001) and cleanliness of kitchen utensils (p= 0.017). In general, the study revealed that IPIs represented a major public health problem in terms of morbidity and economic consequences. It is therefore recommended to local (woreda) health sector and any concerned bodies that systematic, integrated and community-participatory IPIs, prevention and control programs need to be implemented in the study area.
Analysis of Genetic Diversity Among Cultivated Enset (Ensete Ventricosum) Populations from Essera and Kefficho, Southwestern Part of Ethiopia Using ISSR Marker
(Addis Ababa University, 2008-06) Chombe, Dagmawit
This study was conducted with the objective of investigation of genetic variation between populations of cultivated enset and provides information for conservation and improvement of enset. Leaf samples for seventy-one enset plants were collected from two areas of SW Ethiopia (Kefficho and Essera) and genomic DNA was extracted from the samples CTAB extraction method. Inter simple sequence repeats (ISSRs) as a molecular marker was used to assess genetic diversity both within and between populations using two ISSR primers (834 and 826). A total of 26 clear and reproducible bands were amplified from the two primers. Both UPGMA and neighbor joining trees were constructed for each individual and population using Jaccard’s similarity coefficient. The trees indicated two separate clusters which are based on the origin of populations and few intermixing of samples between regions was observed. The PCO analysis also recovered the UPGMA and neighbor joining trees groups. All parameters indicated that the clones of enset from Kefficho are more diverse than clones from Essera. Moreover, partioning of Shannon’s diversity index showed that the majority of the variations were observed within populations of enset than between the two populations. In conclusion, the present study using ISSR analysis, all the diversity parameters confirm that there is high diversity in cultivated Ensete ventricosum populations of SW Ethiopia and that ISSR markers can be successfully applied for the assessment of genetic diversity of this species. Therefore further research on analysis of genetic diversity of cultivated enset population including divergent production areas has to be done and the conservation capacity of institutes both for in-situ and ex-situ should be strengthen. Key Words: - Cultivated Ensete ventricosum, Essera, Ethiopia, Genetic Diversity, ISSR, Kefficho,
Analysis of the Status of a Mixed Semi- arid" j Woodland in Response to Charcoal Production in Elangata Wuas, Kajiado District, Kenya
(Addis Ababa Universty, 2004-06) Meshack, Malo; Fetene, Masresha (Professor)
Understanding charcoal production impact on the woodland status is vital for sustainable management given increasing charcoal demands from growing urban populations. The status of a mixed semiarid woodland was assessed in relation to charcoal production in Kajiado district southern Kenya. Status of the woodland was assessed from 72 circular sample plots and the historical perspective established using maps and discussions with elders. Plots measuring O.OSha were assessed counting seedlings and saplings and measuring tree diameter at breath height along altitudinal gradient /i'om the hilltops to the plains. Charcoal production process and efficiency /i'om traditional eat1h kilns were investigated by comparing outputs and inputs to understand loses. Results show that tree cover (woodland) has increased with discontinuity in species along altitudinal gradient. Tree density decreases from the hilltop to the plains with failure in regenerates especially at the sapling class. Charcoal recovery rate averaged 8% and preference was for A. torti/is, A. mellifera and B. aegyptiaca in that order with basal diameter> IScm for charcoal production. Estimates show supply balanced with demand and points the problem of charcoal production to the low recovety rates and divergence between state and community forest management objectives. Reconciliation of state and community objectives, "boma" enclosures and "mbuzi" woodlots, selective cutting entrenched in enforcement and making of enabling rather than restrictive legislation among others are recommended as strategies that may be pursued to enhance dty woodland contribution to sustainable development. Keywords: Dry woodlands, charcoal production, sustainable exh'actioll
Antagonistic Activities of Pseudomonas Fluorescens Isolates, As A Bicontrol of Botrytis Fabae (Chocolate Spot Disease), Plant Growth Promoter and Inducer of Physiological Activities of Faba Bean (Vicia Faba)
(Addis Ababa University, 2012-06) Alemu, Fekadu; Alemu, Tesfaye (PhD)
Plant protection is an important area which needs attention since most of the hazardous inputs added into the agricultural system are in the form of plant protection chemicals. Production of the crop is, however, constrained by several infections including fungal diseases. The present study, Pseudomonas fluorescens isolates possess a variety of promising properties which make it a better biocontrol agent.Twelve Pseudomonas fluorescens isolates from rhizospheric soil of faba bean were evaluated for their antagonistic activity against Botrytis fabae that is known to attack faba bean crops. All Pseudomonas fluorescens isolates are employed in controlling chocolate spot diseases of plant. P. fluorescens10 (88.1%) showed high antagonistic activity against Botrytis fabae. In addition, all isolates were tested for antifungal activity against Botrytis fabae. All isolate of Pseudomonas fluorescens are indicated successfully employed in controlling chocolate spot diseases of plant due to their antifungal metabolites.The antifungal compounds were extracted from all P. fluorescens isolates with equal volume of ethyl acetate, hexane and methanol.The antifungal compounds extracted with ethyl acetate, hexane and methanol from P f3, P f8 and P f3 isolates at 0.1% concentration completely inhibited the pathogen growth respectively. Four fungicides were tested against B. fabae and Curzate ® WP and Sancozeb 80% were prevented mycelia growth at higher concentration (80mg/ml per plate). All isolates Pseudomonas fluorescens were assessed for their plant growth promoting activity based on their ability to produce hydrogen cyanide (HCN), siderophores, indole acetic acid (IAA), ammonia and phosphate solubilization. The results indicated that all most of the isolates tested possess plant growth promoting traits. Bio-primed faba bean seed with P f9 and P f10 for pathogencity test in green house was indicated to show positive result. Two isolates of P f9 and P f10 was reduced both disease severity and incidence, increasing faba bean number of leaves per plant, number of branches per plant, height of plants, root length of plant and lateral roots and number of nodule. The present study was also carried out for estimation of total phenols and flavonoids present in fresh faba bean leaf extract with ethanol. Applying the P f9 and P f10 by bio-primed seed of faba bean treatment enhanced the accumulation of total phenols and flavonoids compared to untreated infected and uninfected untreated faba bean. So it could be concluded that the used P f9 and P f10 could resist the detrimental effects of Botrytis fabae on the plant growth and yield. These isolates can be used as potential biofertilizers and also as biocontrol agents. Key words: Antifungal compounds, Botrytis fabae, Biocontrol, faba bean, Pseudomonas fluorescens, secondary metabolites
Antibiotic production and optimization of culture condition of Actinomycetes from some Soda Lakes of Ethiopia.
(Addis Ababa University, 2011-07) Mehabie, Daniel; Gessesse, Amare (PhD)
The demand for new antibiotics increased due to the misuse and over use of antibiotics in various sectors creating an evolutionary pressure and resulting in multi drug resistant strains which result in increment of morbidity and mortality in the world. The main objective of this study was to explore the potential of alkaliphilic actinomycetes isolated from three Ethiopian soda lakes. About 171 isolates were screened for antibiotic production using cell free culture supernatant taken from the submerged fermentation and ethyl acetate crude extract of the culture, of which 93.6% of them showed antibiotic activity with cell free culture supernatant and 76 % of them with crude ethyl acetate extract against the test microorganisms used. Based on broad spectrum activity, zone of inhibition obtained and their activity with the use of crude ethyl acetate extract, two isolates LCHACT17and LABACT21 were chosen for further characterization. Antibiotic production was favored when phosphate concentrations was 0.2 % for LCHACT 17 and for LABACT 21. Yeast extract and sodium nitrate (for LCHACT 17) and combination of casein and potassium nitrate (for LABACT 21) were suitable nitrogen sources for antibiotic production. From the carbon sources used soluble starch was the best carbon source for antibiotic production by LCHACT17 while sucrose was found to be preferred carbon source by LABACT 21. Similarly it was observed that 1% sodium chloride concentration was favorable for antibiotic production by both isolates and the pH parameter indicated that pH10 (for LABACT 21) and pH11 (for LCHACT17) were the optimum pH for antibiotic production. The cell free culture supernatant of both isolates was stable at alkaline pH and decreases in activity at lower pH (pH 6 and below). The cell free culture supernatant of LCHACT17 was stable up to 60oc while LABACT 21 was stable up to 40 oc. The minimum inhibitory concentration (MIC) of LCHACT17 crude ethyl acetate extract against Streptococcus pneumonia was 12.5 mg/ml. Key words/ phrases: Alkaliphiles, Antibiotics, Disk diffusion.
Anticancer Activities of Solvent Fractions and of Sesquiterpene Lactones Isolated from Selected Ethiopian Traditional Medicinal Plants
(Addis Ababa University, 2020-07-07) Tuasha Nigatu; Petros Beyene (Professor)
The incidence and mortality of breast cancer in women is increasing worldwide. Breast cancer has high intertumoral and intratumoral heterogeneity. Cancer stem cells (CSCs) are one of the many subpopulations of cancer cells and are involved in tumor initiation, progression, evolution and metastasis, and are believed to be responsible for chemotherapeutic resistance. The present study investigated in vitro anticancer activities of extracts from seven medicinal plants traditionally used to treat breast cancer in Ethiopia. Chemical compounds were also isolated from the most potent bioactive fractions. The study determined cytotoxicity of the crude methanol extracts (80 %, v/v) and that of solvent fractions (1:1, v/v) of the most cytotoxic ones. Furthermore, the anti-CSCs potency of the bioactive solvent fractions and the isolated compounds were also investigated. Vacuum liquid chromatography, preparative thin layer chromatography, column chromatography and high-resolution electrospray ionization mass spectrometry (HR-ESI-MS) were employed for the phytochemical characterization. Cytotoxicity of the phytochemicals against the human breast cancer cell lines, JIMT-1, HCC1937 and MCF-7 and the normal-like breast epithelial cell line, MCF-10A, was determined by a spectrophotometric MTT assay. To investigate specific activity against CSCs, flow cytometric determination of the aldehyde dehydrogenase (ALDH) positivity and determination of CD44+/CD24- CSC subpopulations as well as the colony forming efficiency (CFE) in a serum-free soft agar iv were performed. The effects of phytochemical treatment on tumor necrosis factor-α (TNF-ɑ)-induced translocation of the nuclear factor-kappa B (NF-κB) to the nucleus and on cell migration in a wound healing assay were also investigated. The half maximal inhibitory concentrations (IC50) were determined for the crude methanol extract of Sideroxylon oxyacanthum (0.09 μg/mL, MCF-7), Clematis simensis (0.17 μg/mL, HCC1937) and Dovyalis abyssinica (0.21 μg/mL, MCF-7). Ethyl acetate solvent fraction of V. leopoldi was the most cytotoxic against JIMT-1 cells (IC50 = 0.87 μg/mL). The bioactive solvent fractions of V. leopoldi, S. oxyacanthum and C. simensis showed dose dependent reduction in the ALDH+ subpopulation of JIMT-1 cells. The chloroform fraction of C. simensis (80 μg/mL) completely blocked CFE in JIMT-1 cells. The bioactive solvent fractions of V. leopoldi, S. oxyacanthum and C. simensis significantly reduced cell migration (P<0.05). The ethyl acetate fraction of V. leopoldi (0.87 μg/mL) significantly reduced the number of NF-κB positive nuclei (P<0.001). Seven compounds - four sesquiterpene lactones and three flavonoids, were isolated from V. leopoldi. Among the sesquiterpene lactones, one was a novel compound (“Ndb21a2-P”, C20H26O8, M. Wt. = 394.42), which was highly cytotoxic (IC50 = 1.6 μM) to JIMT-1 cells. Whereas all sesquiterpene lactones significantly reduced cell migration (P<0.05), the compound Vernomenin was most effective (P<0.005) in reducing the ALDH+ CSC subpopulation. Also, another isolate, 11ß,13- dihydrovernodalin, resulted in significant reduction in NF-κB positive nuclei (P<0.05). The study showed V. leopoldi to be the most cytotoxic medicinal plant to cancer cells and the sesquiterpene lactones isolated from it had desirable CSCs-specific activities. The study further showed the importance of systematic selection of traditional medicinal plants for anticancer experimental studies. In conclusion, it is recommended that an in-depth investigation into the chemotherapeutic potentials of the sesquiterpene v lactones from V. leopoldi and their structural analogues, be considered as this could augment the global breast cancer drug discovery research.
Antifungal Metabolites from Submerged Culture of Ganoderna Lucidum (Polypore)
(Addis Ababa University, 1991-06) Bitew Adane; Abate Dawit (PhD)
About 60 different basidiomycete cultures were screened for antimicrobial secondary metabolites in submerged culture grown in four different media. Ten (17%) of them produced antimicrobial secondary metabolites. Production medium, duration of growth, and the most susceptible test organisms for each producing strain were established. Among basidiomycetes screened for antimicrobial activity, the culture filtrate extract of the Ethiopian strain of the polypore, Ganodemw lucidum produced the most effective antifungal compounds. The cu/~lral characteristics, growth in submerged culture of the polypore and isolation methods of the two antifungal antibiotics are described. Medium A (Yeast extract malt extract glucose medium) was a better medium for the production of the two antifungal agents. These compounds were released to the culture fluid and the maximum amount of antifungal compounds is obtained after 12 days of submerged growth at 120 revolution per minute (rpm). TIle two antifungal metabolites (20lA and 201B) isolated from culture filtrated were biologically characterized. TIlese metabolites had a wide spectrum of antifungal activity and affect the growth of several saprophytic as well as pathogenic fungi. The minimal inhibitory concentration (MIG) of 20lA against Candida albicans and Candida pseudotropicalis was less than 1 mcg/ml and 1-5 mcg/ml respectively. Inhibition diameter zone of 36 mm was produced when 10 mcg/disc of 20lA was applied on agar medium seeded with AspergHlus flavus. 20lA was also a potent inhibitor of spore gemlination. No spores of Aspergillus niger were germinated at a concentration of 10 mcg/ml of the antibiotic. Bacteria were affected only at high concentration. Antibiotic 20lA was more active than antibiotic 201B. A comparison of antifungal activity against dennatophytes showed that the efficacy of 20lA was comparable to griseofulvin. Treatment of sheep erythrocytes with the two antifungal antibiotics up to 100 mcg/disc did not show any lytic effect on sheep red blood cel/s. Application of 1 mg/1Ocm' of cn/de extract on a shaved rabbit skin showed no demlatotoxic reactions.
Antimicrobial Activity of Solvent-Extracts of Cucumis Ficifolius and Zehneria Scabra on Some Test Microorganisms
(Addis Ababa University, 2011-08) Gelana Tegenu; Mekonnen Yalemtsehay (Professor)
The crude chloroform, ethyl acetate, acetone, methanol and ethanol extract of the leaves of Cucumis ficifolius and Zehneria scabra were tested against in vitro antibacterial activity of five human pathogenic bacteria using disc diffusion method and agar dilution method for Minimum Inhibitory Concentration (MIC). Pseudomonas aeruginosa and Shigella boydii were susceptible test organism for the ethyl acetate and acetone extracts of the leaves of C. ficifolius with inhibition zones of 14±0.577mm, 12±0.577mm and an MIC of 0.781mg/ml, 3.125mg/ml respectively, but Escherichia coli and Salmonella typhi were the most resistant bacteria to all extracts of the leaves of this plant species with no inhibition zones. Staphylococcus aureus and E. coli were found to be the most susceptible bacteria for the ethyl acetate and acetone extracts of the leaves of Z. scabra with inhibition zones of 22.6±0.33mm, 14±0.577mm and MIC of 0.781mg/ml, 1.56mg/ml respectively. However S. typhi was the most resistant to all extracts of the leaves of this plant with no inhibition zone. The acetone extracts of C. ficifolius and the ethyl acetate extracts of Z. scabra were most potent but the chloroform extracts of both medicinal plants were ineffective against all bacterial and fungal test organisms. C. ficifolius and Z. scabra didn’t show any inhibitory activity against Botrytis and Fusarium. It can be concluded that C. ficifolius and Z. scabra had shown antibacterial activity having potential for further study to serve as source of antibacterial agents. Key words and phrases: Antibacterial activity, antifungal activity, minimum inhibitory concentration, Cucumis ficifolius, Zehneria scabra.
Assessing the Effect of Human Impact on Plant And Soil Conservation on Hill Slope at Mechaworeda West Gojjam of Amhara Regional State
(Addis Ababa University, 2016-09) Mesfun, Teklebrhan; Warkineh, Bikila (PhD)
Degradation of ecosystem and subsequent reduction in services are major problems to sustain livelihoods in sub Sahara African region. As part of SSA Ethiopia faces various hurdles related in environmental degradation particularly in plant and soil conservation. Land is one of the most important assets. However conversion of natural vegetation and habitat destruction is main challenge in Mecha Woreda particularly in Addis Alem, Felege Hiwot and Midre Genet Kebeles. Although several stakeholders such as scientists, local and regional government bodies are working to improve plant and soil conservation, the problem persist in the study area due to inadequate efforts and various human induced negative impacts. This study aimed to identify the effect of human impact on plant and soil conservation, compare with similar area but model Kebele and come up at possible recommendation related with the effect of human impact on plant and soil conservation on hill slope. Three sites were selected purposely due to the fact that they are devoid of vegetation and highly eroded in the Woreda. Sampling design approach was used through stratified random sampling for farmers’ questionnaire. Data was collected through field observation, interview, questionnaire and secondary data from recorded document. The data was organized through tabular and analyzed in frequency, percentage and figuratively. several factors contribute this study including poor socioeconomic conditions, cutting of tree for fire wood, charcoal production, home construction, furniture’s and infrastructure expansion such as road construction. The result of the study showed soil erosion as a result of those human negative impacts. The present study showed severe soil erosion due to these anthropogenic factors. Keywords: Impact, Plant, Soil and Conservation.
Assessment of Functional Food Plants Commonly Used by People Living in Libokemekm District South Gondar Zone, Northwest Ethiopia
(Addis Ababa University, 2017-08) Haile, Milikit; Wondemu, Tigist (PhD)
Functional food can be a natural food or it can contain one or more specific components which have functional influence on the health and well-being of the consumer. It beneficially affects target functions beyond its basic nutritional functions. The aim of this study is to assess the most common functional food plants used in Libo-kemkem district, South Gondar Zone, Northwest Ethiopia. The target population consists of inhabitants living in the Yifag kebele indifferent gotti and the sample population derived from residents aged 40 years registered in the official population census of the Yifag kebele.Data was collected using a structured questioner for qualitative data and in depth interview and focus group discussion to collect quantitative data. Various ethnobotanical techniques were used to collect and analyze the data: guided field walk and observation, group discussion, preference raking use direct matrix combined with descriptive statistical analysis. A total of 34 species belonging to 31genera and 18 families were recorded as functional food plants. Triticum dicoccum Schübl. And Hordeum vulgare L. stood first in being the most multipurpose functional food plants followed by Allium sativum L., and Nigella sativa L. and Sorghum bicolor (L.) Moench was the least. Seed was found to be the most frequently utilized part (36.3 %). Traditional healers use seeds of the functional foods to prepare remedies and also recommend them for their functional uses. The most frequently used functional food plants and parts might be the result of long history of intimacy in cultivating as basic food sources. Since there are different varieties of these functional food plants, seed collection and preservation is highly recommended. Keywords: Ethnobotany, Functional food plants Food and Medicine, Health, Libo-kemkem
Assessment on the Outcomes of Promotion of Nutrition Education on Dietary Diversity Among Women’s of Reproductive Age (15-49 Years) and Children Aged 6-36 Month in Tigray Regional State Selected Rural Kebeles
(Addis Ababa University, 2018-11-03) Nega, Fetene; Baye, Kaleab (PhD)
Poor nutrition disproportionately affects women and children in rural areas of low and middle income countries. This is linked with 45 % of child death. Mothers/caregivers inadequate knowledge of Infant and Young Child Feeding (IYCF) practices and poor cultural belifes increases the risk of nutrition disorders. Integrating nutrition education with food preference and nutrition-sensitive agriculture has the potential to improve diets, but rigorous evaluation of this approach are limited. Therefore, the present study investigated the outcomes of promotion of nutrition education in the presence and absence of nutrition-sensitive agriculture interventions on WRA and their children dietary intake in the rural farming community. Quasi-experimental study with two arms 1) NSA+BCC and 2) BCC alone was conducted from February-May 2018 to assess the outcomes of promotion of nutrition education on dietary diversity among women’s of reproductive age and children aged 6 to 36 months in Tigray region selected rural kebeles. The study was designed to include 200 mother-child pairs and sampling were directed by using simple random sampling technique to select the study participants. Women and children dietary intake have been measured using qualitative open 24-hrs dietary recall technique adopted from FAO and WHO. In the baseline assessment, proportion of minimum DD was extremely low (4.9% women and 4.1% children) in the BCC group. At the endline, 20.8% of women and 32.5% children from the NSA+BCC group has met the recommended minimum DD. NSA+BCC significantly improved the proportion of women and children meeting minimum DD, when compared to BCC alone (P<0.05). BCC alone had also shown positive trend in dietary diversity between baseline and endline values. Although both BCC and NSA+BCC improve dietary diversity, the increase in the proportion of children and women meeting the minimum DD was significantly higher when BCC and NSA were combined. Therefore, in rural farming communities integrating BCC that is informed by food preference along with NSA is recommended to improve diets of women and children.
The Benefits of Acacia abyssinica (Hochst.) ex. Benth. (Fabaceae) in the Restoration of the Threatened Juniperus procera (Hochst.) ex. Endl. (Cupressaceae)
(Addis Ababa University, 2012-06) Kagnew, Birhanu; Negash, Legesse (Professor)
The study was conducted in the “Center for Indigenous Trees Propagation and Biodiversity development in Ethiopia”. This thesis presents analysis of the contribution of Acacia abyssinica for the restoration of the threatened Juniperus procera. The general purpose of the study was to examine the role of A. abyssinica in the restoration of the threatened J. procera on degraded and bare landscape. To achieve this objective, different size sampling plots were used for both tree and soil data collections, along the systematically laid transect lines. Accordingly, a total of 24 sampling plots were constructed, inside each sample plot, the growth parameters, viz. tree height, d.b.h, crown length, crown diameter, branch numbers, branch length and status of soil physicochemical properties in the two sub-sites was recorded and examined. The growth potential of the studied tree was analyzed. The findings of the study revealed that the mean growth difference of J. procera in the two sub-sites was significant (p < 0.05) and its growth potential in all parameters was considerably higher in A. abyssinica influenced sub-site than the control sub-site. The results showed that the presence of A. abyssinica were paramount important for the restoration of the endangered J. procera. The soil analysis result revealed that there is significant mean difference (p < 0.05) for soil organic carbon, total nitrogen and soil textures in the two soil depths and across the two sub-sites. Total nitrogen, organic carbon, EC, available phosphorus and CEC except soil pH were decreased with increasing soil depths which is an indication of surface soil fertility restoration. Soil fertility was different across the two sub-sites. This might be due to either the presence or absence of nitrogen fixing as well as necromass production of A. abyssinica. The significance of the study was to provide a basis for further restoration studies that contributes towards restoration, protection, regeneration and conservation of useful endangered tree in particular and biodiversity in general. Keywords: Restoration, nitrogen fixation, growth performance, J. procera, Soil fertility.
Biodiversity Management in Oaaddegoyo (Traditional Home Gardens) by Kaficho People of Bongaarea (Southwestern Ethiopia) : An Ethnobotanic Approach
(Addis Ababa University, 2000-06) Woldeyes, Feleke; Demissew, Prof. Sebsebe
The study was conducted in three villages around 80nga (Southwest Ethiopia) to investigate the role of the local people in managing biological diversity through agricultural activities. The Kafichos, the indigenous people of the study area, are settled farmers who practice traditional home gardening. Their enset based home garden, which consists of a complex mixture of annual and perennial plants, is locally called Oaaddegoyo; and provides them with almost every thing required for subsistence. Data on vegetation (species record, cover-abundance, number of individuals, and plant specimens), and soil samples were collected from sample plots. Ethnobatanic information was gathered by conducting open ended discussions with key informants, owners of home gardens and other family members. The collected plant specimens were identified in the Niational Herbaruim (ETH). The vegetation data was analysed using the computer program SYNTAX and five clusters were recognixed: Ensete·Xanthosoma community, Ensete·Coffea community, Ensete·Brassica community. Ensete·Xanthosoma·Saccharum community and Ensete·Xanthosoma·Nicotiana community. The clusters were compared for the mean values of the soil chemical factors using the ANOVA test. A total of 170 plant species were recorded from the 21 Oaaddegoyo (home gardens) of which 47% were found to be protected or tolerated. Although a decrease in total number of plant species per village with an increase in altitude was observed, the ANOVA (Analysis of Variance) test result indicated no sighificance difference among the three villages in the number of species per garden. The Daaddegoyo whose framework is made by Ensete ventricosum is strongly linked to the other two land·use systems: Kubbo ('managed forest") and Guudo (Inlact forest). It is a stable agroecosystem that harbours a Significant biodiversity. and this has resulted from innovative processes by local farmers over generations. Therefore, the Oaaddegoyo is an in·situ repository of crop germplasm and deserves protection.
The Biological Characteristics and Potentials for Use in Agroforestry of Two Miombo Woodland Tree Species
(Addis Ababa Universty, 2003-06) Kafumu, Monica; Fetene, Masresha (Professor)
Two indigenous tree species of Tanzanian miombo woodland were studied to explore some of their biological charactellstics and potential for use in agroforestry. These were selected by farmers from among four most frequently encountered tree species found within the study area using direct matrix ranking approach. The selection of the study species was based on degree of preference by farmers. Semi-structured interviews were administered on 60 informants to explore information on ecological aspects of the study sites, biological characteristics and multipurpose nature of the study species. Studies on the ecology and growth characteristics and their influence on the environment were conducted in four sites i.e. two sites for each study species. A total of 40 quadrats (50 by 20 m), 10 in each of the study sites, were established for study of vegetation information, tree characteristics and estimation of undercanopy vegetation cover. To investigate the influence of the study species on undercanopy soil, samples were collected from three study trees for each site. The soil samples were collected from 0-5 and 25-30 cm depths at 100, 250 cm and outcanopy distances along the transect radiating from tree bole. Bulk density, texture, pH, electrical conductivity, organic matter, total nitrogen, available phosphorus and exchangeable potassium of soil samples were analyzed. Vegetation cover and soil properties outside tree canopies were also investigated for comparison purposes. Sclerocarya birrea (A. Rich.) Hochst. Subsp. caffra (Sond.) Kokwaro. and Brachystegia lIlicrophylla Harms ranked first (1487) and second (1170) respectively in direct matrix ranking and hence were selected for this study. Site two study trees had highest average tree density. B. microphylla had higher mean tree height, canopy depth, and crown cover whereas S. birrea had higher mean DBH. In all sites undercanopy species diversity was significantly higher than species diversity outside the tree canopies. Soil mineral elements decreased with depth and distance from the tree bole. Significantly higher levels of nutdent elements under the tree canopies revealed an increase in input from the study trees. This indicates that the study trees enriched soil under their canopies thus creating suitable microenvironment, which promotes the development of understorey herbaceous layer. Comparison of levels of nutrients under the canopies of the two species indicated that B. lIlicrophylla had significantly higher percentage of total nitrogen at all depths than S. birrea. This may be due to the fact that B. lIIicrophylla, which is a leguminous tree, may fix nitrogen and hence increase nitrogen content under its canopy zones. S. birrea had a wide range of uses, indicating its multipurpose nature. It is concluded that both B. lIIicrophylla and S. birrea display high agroforestry potential and hence are recommended for use in agroforestry practices in miombo zones. However, the results of this study are subject to fUlther verifications.
Biological Consequences of Pleistocene Glaciations in East African Afro-Alpine Environment As Inferred From Molecular Data of Some Key Plant Species
(Addis Ababa University, 2007-07) Assefa, Adane; Nemomissa, Sileshi (Professor)
The afro-montane/-alpine regions representing biological 'sky islands' comprise the high mountains of Ethiopia and tropical East Africa. The vegetation of the regions is characterized by fragmentation among the various mountain massifs with numerous local endemic species. Most plant species in these ‘sky islands’ are quite different from those occurring in their respective immediate surrounding lowlands. However, some primarily arctic-alpine plants also occur in the mountains, as Arabis alpina. It has been suggested that this plant elements are Tertiary relict, but a recent range-wide study of A. alpina suggested that the species colonized the region twice during the Pleistocene period. In addition to such immigrant species, some other key plant species, as Salvia merjamie and Cerastium afromontanum are very common in sub-alpine and montane forests of the ‘sky islands. In this study, two overlapping phases of investigations have been carried out on these three species using two basic molecular biological techniques: in the first phase, the detail colonization history of A. alpina was investigated in the afro-alpine regions based on chloroplast DNA (cpDNA) sequences, and in the second phase, the phylogeographic structures and conservation status of the three species were studied using amplified fragment length polymorphic DNA data (AFLP fingerprinting) obtained from 11 mountain systems, where present-day populations are often limited to isolated mountain tops. In the first phase, the results confirm the twice-into-Africa scenario. The Asian lineage is also confined to the mountains closest to the Arabian Peninsula, on opposite sides of the Great Rift Valley (GRV), suggesting long-distance dispersal of the A. alpina lineage. The African lineage is divided into two phylogeographic groups with distinct geographic distribution. The observed pattern is consistent with isolation of the African lineage in at least two interglacial refugia, located on separated highlands, followed by range expansion in cooler period(s), when the afro-alpine habitat extended further down the mountains. Several long-distance dispersal events across the GRV are also suggested by haplotypes observed outside the area occupied by the phylogeographic groups they belonged to. In the second phase of the investigation, in the Ethiopian and tropical East African mountains, A. alpina showed high and clearly structured genetic variability. The fragmented structure in the mountains indicated that A. alpina disperses little among established populations. However, occasional long-distance dispersal events were also suggested in all parts of the ranges, similar to the cpDNA data findings. In S. merjamie and C. afromontanum which may consist of the subspecies complex, the diversity is so high for the former and very low for the latter species in certain isolated mountain regions in Ethiopia (i.e. the Simen Mts and Gara Muleta). The present analyses did also reveal very complex geographical structuring and phylogeographic patterns among the study areas. Moreover, the AFLP data clearly indicated very distinct and genetically highly divergent individuals, which might represent possible cryptic subspecies signifying the call for future detail morphological assessments of the species in the region. Key words: cpDNA, AFLP, Arabis alpina, Salvia merjamie, Cerastium afromontanum, phylogeography, genetic diversity, refugia, afro-alpine, afro-montane, East Africa, Pleistocene.

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